Rev.2.1_01 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS S-8337/8338 Series The S-8337/8338 Series is a CMOS step-up switching regulator which mainly consists of a reference voltage circuit, an oscillator, an error amplifier, a PWM controller, an under voltage lockout circuit (UVLO), and a timer latch short-circuit protection circuit. Because its minimum operating voltage is as low as 1.8 V, this switching regulator is ideal for the power supply of an LCD or for portable systems that operate on a low voltage. The internal oscillation frequency can be set up to 1.133 MHz, via the resistor connected to the ROSC pin. With the S-8337 Series, the maximum duty ratio of PWM control can be controlled by the resistor connected to the RDuty pin. With the S-8338 Series, the maximum duty ratio is fixed (to 88%). The phase compensation and gain value can be adjusted according to the values of the resistor and capacitor connected to the CC pin. Therefore, the operation stability and transient response can be correctly set for each application. The reference voltage accuracy is as high as 1.0 V1.5%, and any voltage can be output by using an external output voltage setting resistor. In addition, the delay time of the short-circuit protection circuit can be set by using the capacitor connected to the CSP pin. If the maximum duty condition continues because of short-circuiting, the capacitor externally connected to the CSP pin is charged, and oscillation stops after a specific time. This condition is cleared by re-application of power or by setting the switching regulator (S-8338 Series) to the shutdown status. A ceramic capacitor or a tantalum capacitor is used as the output capacitor, depending on the setting. This controller IC allows various settings and selections and employs a small package, making it very easy to use. Features 1.8 V to 6.0 V 286 kHz to 1.133 MHz (selectable by external resistor) 47 to 88.5% (selectable by external resistor) (S-8337 Series) Fixed to 88% typ. (S-8338 Series) Reference voltage: 1.0 V1.5% UVLO (under-voltage lockout) function: Detection voltage can be selected from between 1.5 V and 2.3 V in 0.1 V steps. Hysteresis width can be selected from between 0.1 V and 0.3 V in 0.1 V steps. Timer latch short-circuit protection circuit: Delay time can be set using an external capacitor. Soft-start time can be selected in three steps, 10 ms, 15 ms, and 20 ms. Soft-start function: Phase compensation external setting: Adjustable by connecting resistor and capacitor in series to GND. Shutdown function: S-8338 Series, shutdown current consumption: 1.0 A max. 8-pin SON(A), 8-pin TSSOP Small package: * Low voltage operation: * Oscillation frequency: * Maximum duty: * * * * * * * Applications * Power supplies for LCDs and CCDs * Power supplies for portable equipment Packages Package name 8-Pin SON(A) 8-Pin TSSOP Package PN008-A FT008-A Drawing code Tape PN008-A FT008-E Seiko Instruments Inc. Reel PN008-A FT008-E 1 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Block Diagram SD RDuty (S-8337) or ON/OFF (S-8338) L VIN ROSC UVLO M1 CIN VOUT + PWM - comparator EXT Timer latch short-circuit protection circuit VSS CSP + Error amplifier - Reference voltage (1.0 V) soft-start circuit CC RZ CZ Figure 1 Block Diagram 2 CFB RFB1 Oscillator Maximum duty circuit Seiko Instruments Inc. CL FB RFB2 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Product Name Structure Product name S-833 x A x x x - xxxx Package name (abbreviation) and packing specification. P8T1: 8-Pin SON(A), tape T8T1: 8-Pin TSSOP, tape Soft-start time setting A: 10 ms B: 15 ms C: 20 ms UVLO setting A: 2.3 V B: 2.2 V C: 2.1 V D: 2.0 V E: 1.9 V F: 1.8 V G: 1.7 V H: 1.6 V I: 1.5 V UVLO hysteresis setting A: 0.1 V B: 0.2 V C: 0.3 V Pin setting 7: With MaxDuty setting function 8: With Shutdown function Seiko Instruments Inc. 3 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Pin Assignment Table 1 8-Pin SON(A) Top view 1 2 8 7 3 6 4 5 Figure 2 Pin No. Symbol 1 CC 2 FB 3 CSP 4 5 6 VIN EXT VSS 7 ROSC 8 RDuty ON/OFF Description Error amplifier circuit output phase compensation pin Output voltage feedback pin Short-circuit protection delay time setting pin Power supply input pin External transistor connection pin GND pin Oscillation frequency setting resistor connection pin Maximum duty setting resistor connection pin (S-8337 Series) Shutdown pin (S-8338 Series) Table 2 8-Pin TSSOP Top view 1 2 3 4 8 7 6 5 Figure 3 Pin No. Symbol 1 CC 2 FB 3 CSP 4 5 6 VIN EXT VSS 7 ROSC 8 RDuty ON/OFF 4 Seiko Instruments Inc. Description Error amplifier circuit output phase compensation pin Output voltage feedback pin Short-circuit protection delay time setting pin Power supply input pin External transistor connection pin GND pin Oscillation frequency setting resistor connection pin Maximum duty setting resistor connection pin (S-8337 Series) Shutdown pin (S-8338 Series) STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Absolute Maximum Ratings Parameter VIN pin voltage FB pin voltage EXT pin voltage CSP pin voltage CC pin voltage CC pin current ROSC pin voltage ROSC pin current RDuty pin voltage RDuty pin current ON/OFF pin voltage Operating temperature Storage temperature Power dissipation Caution Table 3 Absolute Maximum Ratings (Unless otherwise specified: Ta = 25C, VSS = 0 V) Symbol Absolute Maximum Rating Unit V VIN VSS - 0.3 to VSS + 6.5 VFB VSS - 0.3 to VSS + 6.5 VEXT VSS - 0.3 to VIN + 0.3 VCSP VSS - 0.3 to VIN + 0.3 VCC VSS - 0.3 to VIN + 0.3 ICC mA 10 V VROSC VSS - 0.3 to VIN + 0.3 IROSC mA 10 V VRDuty VSS - 0.3 to VIN + 0.3 IRDuty mA 10 VON/OFF V VSS - 0.3 to VSS + 6.5 Topr -40 to +85 C Tstg -40 to +125 8-Pin SON(A) 300 mW PD 8-Pin TSSOP 300 The absolute maximum ratings are rated values exceeding which the product could suffer physical damage. These values must therefore not be exceeded under any conditions. Seiko Instruments Inc. 5 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Electrical Characteristics 1. S-8337 Series Table 4 Electrical Characteristics (Unless otherwise specified: VIN = 3.3 V, Ta = 25C) Test Circuit 2 2 Parameter Symbol Conditions Min. Typ. Max. Unit Operating input voltage FB voltage VIN VFB 1.8 0.985 1.000 6.0 1.015 V Current consumption ISS1 400 700 A 1 100 -100 160 -60 mA 1 1 100 ppm/C 2 -0.1 +0.1 A 1 fosc x 0.9 fosc fosc x 1.1 kHz 1 1000 ppm/C 1 % 1 EXT pin output current FB voltage temperature coefficient FB pin input current IEXTH IEXTL VFB Ta IFB fosc = 700 kHz VFB = 0.95 V VEXT = VIN - 0.4 V VEXT = 0.4 V Ta = -40C to +85C fosc = 1133 kHz (ROSC = 120 k) fosc = 700 kHz (ROSC = 200 k) Oscillation frequency*1 fosc = 286 kHz (ROSC = 510 k) fosc VFB = 0.9 V Waveform on EXT pin is measured. Oscillation frequency fosc Ta = -40C to +85C temperature coefficient Ta fosc = 700 kHz fosc = 700 kHz (ROSC = 200 k) MaxDuty = 88.5% (RDuty = 100 k) Max. duty*2 MaxDuty MaxDuty = 77% (RDuty = 300 k) MaxDuty = 47% (RDuty = 820 k) tSS = 10 ms, 15 ms, 20 ms Soft-start time tSS Selected in three steps tPRO = 50 ms Short-circuit protection tPRO *3 delay time (CSP = 0.1 F) VUVLO = 1.5 V to 2.3 V UVLO detection voltage VUVLO Selected in 0.1 V steps VUVLOHYS = 0.1 V to 0.3 V UVLO hysteresis width VUVLOHYS Selected in 0.1 V steps ICCH VFB = 2 V CC pin output current VFB = 0 V ICCL Timer latch reset voltage VRTLT MaxDuty MaxDuty MaxDuty +5 -5 tSS x 0.75 tSS 37.5 50 tSS x 1.5 1 ms 75 VUVLO VUVLO VUVLO x 0.95 x 1.05 VUVLOHYS VUVLOHYS VUVLOHYS x 0.6 x 1.4 -75 -50 -37.5 37.5 50 75 0.7 1.0 1.3 1 V 1 mV 1 A V 1 1 1 *1. The recommended range of the resistance (Rosc) for setting the oscillation frequency is Rosc = 120 k to 510 k (fOSC = 286 kHz to 1.133 MHz). However, the oscillation frequency is in the range of typical values when an ideal resistor is externally connected, so actually the fluctuation of the IC (10%) must be considered. *2. The recommended range of the resistance (RDuty/Rosc) for setting the maximum duty is RDuty/Rosc = 0.5 to 4.1 (MaxDuty = 47 to 88.5%). However, the maximum duty is in the range of typical values when an ideal resistor is externally connected, so actually the fluctuation of the IC (5%) must be considered. *3. The short-circuit protection time can be set by the external capacitor, and the maximum set value by the external capacitor is unlimited when an ideal case is assumed. But, use CSP = approximately 0.47 F as a target maximum value due to the need to consider the discharge time of the capacitor. 6 Seiko Instruments Inc. STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 2. S-8338 Series Table 5 Electrical Characteristics (Unless otherwise specified: VIN = 3.3 V, Ta = 25C) Test Circuit 2 2 Parameter Symbol Conditions Min. Typ. Max. Unit Operating input voltage FB voltage VIN VFB 1.8 0.985 1.000 6.0 1.015 V Current consumption ISS1 fosc = 700 kHz VFB = 0.95 V 400 700 ISSS VIN = 6.0 V 1.0 IEXTH IEXTL VFB Ta IFB VEXT = VIN - 0.4 V VEXT = 0.4 V 100 -100 160 -60 mA 1 1 100 ppm/C 2 -0.1 +0.1 A fosc = 1133 kHz (ROSC = 120 k) fosc = 700 kHz (ROSC = 200 k) fosc fosc Oscillation frequency*1 fosc = 286 kHz (ROSC = 510 k) fosc kHz fosc x 0.9 x 1.1 VFB = 0.9 V Waveform on EXT pin is measured Oscillation frequency fosc Ta = -40C to +85C 1000 ppm/C temperature coefficient Ta fosc = 700 kHz Max. duty ratio MaxDuty fosc = 700 kHz (ROSC = 200 k) 83 88 93 % tSS = 10 ms, 15 ms, 20 ms tSS tSS tSS Soft-start time tSS Selectable in three steps x 0.75 x 1. 5 ms tPRO = 50 ms Short-circuit protection 37.5 50 75 tPRO *2 delay time (CSP = 0.1 F) VUVLO = 1.5 V to 2.3 V VUVLO VUVLO VUVLO V UVLO detection voltage VUVLO Selected in 0.1 V steps x 0.95 x 1.05 VUVLOHYS = 0.1 V to 0.3 V VUVLOHYS VUVLOHYS VUVLOHYS mV UVLO hysteresis width VUVLOHYS Selected in 0.1 V steps x 0.6 x 1.4 ICCH VFB = 2 V -75 -50 -37.5 A CC pin output current VFB = 0 V 37.5 50 75 ICCL Timer latch reset VRTLT 0.7 1.0 1.3 voltage Shutdown pin input V VSH 1.8 voltage (High level) Shutdown pin input VSL 0.3 voltage (Low level) Shutdown pin input ISH -0.1 +0.1 current (High level) A Shutdown pin input ISL -0.1 +0.1 current (Low level) 1 Shutdown current consumption EXT pin output current FB voltage temperature coefficient FB pin input current Ta = -40C to +85C 1 A 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 *1. The recommended range of the resistance (Rosc) for setting the oscillation frequency is Rosc = 120 k to 510 k (fosc = 286 kHz to 1.133 MHz). However, the oscillation frequency is in the range of typical values when an ideal resistor is externally connected, so actually the fluctuation of the IC (10%) must be considered. *2. The short-circuit protection time can be set by the external capacitor, and the maximum set value by the external capacitor is unlimited when an ideal case is assumed. But, use CSP = approximately 0.47 F as a target maximum value due to the need to consider the discharge time of the capacitor. Seiko Instruments Inc. 7 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series External Parts When Measuring Electrical Characteristics Table 6 External Parts Element Name Inductor Diode Output capacitor Transistor Oscillation frequency setting resistor Maximum duty ratio setting resistor Short-circuit protection delay time setting capacitor Output voltage setting resistor 1 Output voltage setting resistor 2 FB pin capacitor Phase compensation resistor Phase compensation capacitor 8 Symbol L SD CL M1 ROSC RDuty CSP Manufacturer TDK Corporation Rohm Co., Ltd. Sanyo Electric Co., Ltd. RFB1 RFB2 CFB RZ CZ Seiko Instruments Inc. Part Number LDR655312T 4.7 H RB491D Ceramic 10 F MCH3406 200 k (when fOSC = 700 kHz) 300 k (when MaxDuty = 77%) 0.1 F (when tPRO = 50 ms) 8.2 k (when VOUT = 9.2 V) 1.0 k (when VOUT = 9.2 V) 180 pF 200 k 0.01 F STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Test Circuit Diagram 1. RZ A CZ CIN CC RDuty (ON/OFF) FB ROSC CSP VSS VIN EXT CSP ROSC RDuty Oscilloscope Figure 4 2. RFB1 RDuty (ON/OFF) FB ROSC CFB RZ CZ CC SD RFB2 CL L M1 CIN CSP VSS VIN EXT ROSC RDuty CSP V Figure 5 Seiko Instruments Inc. 9 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Operation 1. Switching control method PWM control (S-8337/8338 Series) The S-8337/8338 Series is a DC-DC converter using a pulse width modulation method (PWM). The pulse width of the S-8337/8338 Series varies from 0% to the maximum duty set by RDuty depending on the load current (the pulse width of the S-8338 Series is fixed to 88%), but its switching frequency does not change. Consequently, the ripple voltage generated from switching can be removed easily via a filter. 2. Soft-start function For this IC, the built-in soft-start circuit controls the rush current and overshoot of the output voltage when powering on or when the ON/ OFF pin is switched to the "H" level. A reference voltage adjustment method is adopted as the soft-start method. The following describes the soft-start function. The raising of the output voltage is controlled by slowly raising the reference voltage of the error amplifier input from 0 V at power on as shown in Figure 6. The soft-start function is realized by controlling the voltage of the FB pin so that it is the same potential as the reference voltage that is slowly raised. A Rail-to-Rail amplifier is adopted as the error amplifier, which means that the voltage is loop controlled so that it can be the same as the reference voltage. The following explains the operation at power on (refer to Figure 7). When VIN is raised from 0 V to 3.3 V, the VOUT voltage rises to a value close to VIN via the inductor L and diode SD. This raises the voltage of the FB pin (VFB) by approximately 0.35 V (when RFB1 = 8.2 k, RFB2 = 1.0 k). Because the reference voltage rises from 0 V, the VFB voltage is higher than the reference voltage while the voltage rises from 0 V to 0.35 V. During this period, the EXT output is low. The EXT output is in the stepped-up status between high and low after the reference voltage reaches 0.35 V and VOUT is slowly raised in accordance with the rising of the reference voltage. Once the reference voltage rises, the voltage cannot be reset (the reference voltage is 0 V) unless the power supply voltage is the UVLO detection voltage or lower or the shutdown pin is the "L" level. Conversely, when the power supply voltage rises up to the reset voltage after it is lowered to the UVLO detection voltage or lower, the output voltage is stepped up by the soft-start function. SD VOUT L PWM Comparator VIN M1 - EXT RFB1 0.5 V 0V + Error amplifier FB CL + CC - Error amplifier reference voltage RZ CZ 10 Figure 6 Seiko Instruments Inc. Vref RFB2 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series (VIN = 0 V3.3 V, VOUT = 9.2 V, RFB1 = 8.2 k, RFB2 = 1.0 k) 3.3 V Input voltage (VIN) 0V tSS 9.2 V Output voltage (VOUT) VOUT x 0.95 V 2.9 V 0V 1.0 V Error amplifier reference voltage 0.35 V 0V 1.0 V FB pin voltage (VFB) 0.3 V 0V 4.0 V EXT pin voltage (VEXT) 0V t (ms) Figure 7 Seiko Instruments Inc. 11 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 3. Shutdown pin (S-8338 Series only) This pin stops or starts step-up operations. Switching the shutdown pin to the "L" level stops operation of all the internal circuits and reduces the current consumption significantly. DO NOT use the shutdown pin in a floating state because it is not pulled up or pulled down internally. DO NOT apply voltage of between 0.3 V and 1.8 V to the shutdown pin because applying such a voltage increases the current consumption. If the shutdown pin is not used, connect it to the VIN pin. Table 7 Shutdown Pin CR Oscillator Output Voltage "H" Operates Fixed "L" Stopped VIN*1 *1. Voltage of VIN from which the voltage drop from the DC resistance of the inductor and the forward voltage of the diode are subtracted VIN ON/OFF VSS Figure 8 4. Timer latch short-circuit protection function This IC has a timer latch short-circuit protection circuit that stops the switching operation when the output voltage drops for a specific time due to output short-circuiting. A capacitor (CSP) that is used to set the delay time of this short-circuit protection circuit is connected to the CSP pin. This IC operates at the maximum duty ratio if the output voltage drops due to output short-circuiting. At the maximum duty ratio, constant-current charging of CSP starts. If this status lasts for a specific time and the CSP pin voltage rises above the reference voltage (1 V), the latch mode is set. Note that the latch mode is different from the shutdown status in that the switching operation is stopped but the internal circuitry operates normally. To reset the latch operation to protect the IC from short-circuiting, either lower VIN to the timer latch reset voltage or lower or lower the level of the shutdown pin to "L". Note that the latch operation is not reset even if VIN falls below the UVLO voltage. 5. UVLO function This IC includes a UVLO (under-voltage lockout) circuit to prevent the IC from malfunctioning due to a transient status when power is applied or a momentary drop of the supply voltage. When UVLO is in the detection state, switching is stopped and the external FET is held in the off status. Once UVLO enters the detection state, the soft-start function is reset. Note that the other internal circuits operate normally and that the status is different from the power-off status 12 Seiko Instruments Inc. STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 6. Error amplifier The error amplifier outputs the PWM control signal so that the voltage of the FB pin is held at a specific value (1 V). By connecting a resistor (RZ) and capacitor (CZ) to the output pin (CC pin) of the error amplifier in series, an optional loop gain can be set, enabling stabilized phase compensation. 7. Operation The following are basic equations [(1) through (7)] of the step-up switching regulator (refer to Figure 9). L CONT VIN M1 D VOUT EXT FB CL VSS Figure 9 Step-up Switching Regulator Circuit for Basic Equations Voltage at the CONT pin at the moment M1 is turned ON (current IL flowing through L is zero), VA: VA = VS*1................................................................................................................(1) *1. VS: Non-saturated voltage of M1 Change in IL over time: dlL VL VIN - VS = = dt L L ..................................................................................................(2) Integration of the above equation: VIN - VS IL = *t L .....................................................................................................(3) IL flows while M1 is ON (ton). This time is determined by the oscillation frequency of OSC. Peak current (IPK) after tON: VIN - VS IPK = * tON L ................................................................................................(4) The energy stored in L is represented by 1 * L(IPK)2. 2 When M1 is turned OFF (tOFF), the energy stored in L is released via a diode, generating a reverse voltage (VL). VL: VL = VOUT + VD *2 - VIN .............................................................................................(5) ( *2. ) VD: Diode forward voltage The voltage on the CONT pin rises only by VOUT + VD. Seiko Instruments Inc. 13 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Change in current (IL) flowing through the diode into VOUT during tOFF: dlL VL VOUT + VD - VIN = = dt L L .........................................................................................(6) Integration of the above equation is as follows: VOUT + VD - VIN IL = IPK - *t L ....................................................................................(7) During tON, energy is stored in L and is not transmitted to VOUT. When receiving output current (IOUT) from VOUT, the energy of the capacitor (CL) is used. As a result, the pin voltage of CL is reduced, and goes to the lowest level after M1 is turned ON (tON). When M1 is turned OFF, the energy stored in L is transmitted via the diode to CL, and the pin voltage of CL rises drastically. Because VOUT is a time function indicating the maximum value (ripple voltage: Vp-p) when the current flowing through the diode into VOUT and the load current IOUT match. Next, this ripple voltage is determined as follows. IOUT vs t1 (time) from when M1 is turned OFF (after tON) to when VOUT reaches the maximum level: VOUT + VD - VIN IOUT = IPK - * t1 L ..................................................................................(8) L t1 = (IPK - IOUT ) * VOUT + VD - VIN ..............................................................................(9) When M1 is turned ON (after tOFF), IL = 0 (when the energy of the inductor is completely transmitted): Based on equation (7), L tOFF = V OUT + V D - V IN IPK ..........................................................................................(10) When substituting equation (10) for equation (9): IOUT t1 = tOFF - * tOFF IPK .............................................................................................(11) Electrical charge Q1 which is charged in CL during t1: VOUT + VD - VIN t1 VOUT + VD - VIN 1 2 Q1 = 0t1 ILdt = IPK * 0t1 dt - * 0 tdt = IPK * t1 - * t1 L L 2 ................(12) When substituting equation (12) for equation (9): 1 IPK + IOUT Q1 = IPK - (IPK - IOUT ) * t1 = * t1 2 2 ....................................................................(13) A rise voltage (Vp-p) due to Q1: 1 IPK + IOUT Q1 = * * t1 ...................................................................................(14) CL CL 2 When taking into consideration IOUT consumed during t1 and ESR*1 (RESR) of CL: Vp - p = Vp - p = *1. 14 1 IPK + IOUT IOUT * t1 Q1 IPK + IOUT = * ......................................(15) * t1 + * RESR - CL CL 2 2 CL Equivalent Series Resistance Seiko Instruments Inc. STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series When substituting equation (11) for equation (15): Vp - p = (IPK - IOUT )2 * tOFF + IPK + IOUT * RESR ..............................................................(16) 2IPK CL 2 Therefore to reduce the ripple voltage, it is important that the capacitor connected to the output pin has a large capacity and a small ESR. Seiko Instruments Inc. 15 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series External Parts Selection 1. Inductor The inductance has a strong influence on the maximum output current (IOUT) and efficiency (). The peak current (IPK) increases by decreasing L and the stability of the circuit improves and IOUT increases. If L is decreased further, the efficiency falls, and IOUT decreases if the current drive capability of the external transistor is insufficient. The loss of IPK by the switching transistor decreases by increasing L and the efficiency becomes maximum at a certain L value. Further increasing L decrease the efficiency due to the loss of the DC resistance of the inductor. IOUT also decreases. If the oscillation frequency is higher, a smaller L value can be chosen, making the inductor smaller. In the S-8337/8338 Series, the oscillation frequency can be varied within the range of 286 kHz to 1.133 MHz by the external resistor, so select an L value best suited to the frequency. The recommended value is between 2.2 H and 22 H. When selecting an inductor, note the allowable current of the inductor. If a current exceeding this allowable current flows through the inductor, magnetic saturation occurs, substantially lowering the efficiency and increasing the current, which results in damage to the IC. Therefore, select an inductor so that IPK does not exceed the allowable current. IPK is expressed by the following equations in the discontinuous mode and continuous mode. IPK = IPK = 2 IOUT(VOUT + VD - VIN) ( discontinuous mode ) ..................................................................(17) fosc * L VOUT + VD (VOUT + VD - VIN) * VIN * IOUT + (continuou s mode) VIN 2 * (VOUT + VD) * fosc * L ................................................................(18) fOSC = Oscillation frequency, VD 0.4 V. 2. Diode Use an external diode that meets the following requirements. * Low forward voltage * High switching speed * Reverse breakdown voltage: VOUT + [Spike voltage] or more * Rated current: IPK or more 3. Capacitors (CIN, CL) The capacitor on the input side (CIN) can lower the supply impedance and level the input current for better efficiency. Select CIN according to the impedance of the power supply to be used. The capacitor on the output side (CL) is used to smooth the output voltage. Select an appropriate capacitance value based on the I/O conditions and load conditions. A capacitance of 10 F or more is recommended. By adjusting the phase compensation of the feedback loop using the external resistor (RZ) and capacitor (CZ), a ceramic capacitor can be used as the capacitor on the output side. If a capacitor whose equivalent series resistance is between 30 m and 500 m is used as the output capacitor, the adjustable range of the phase compensation is wider; however, note that other characteristics may be affected by ripple voltage or other conditions at this time. The optimal capacitor differs depending on the L value, capacitance value, wiring, and application (output load), so select the capacitor after performing sufficient evaluation under the actual usage conditions. 16 Seiko Instruments Inc. STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 4. External transistor A bipolar (NPN) or enhancement (N-channel) MOS FET transistor can be used as the external capacitor. 4-1. Bipolar (NPN) type The driving capability when the output current is increased by using a bipolar transistor is determined by hFE and Rb of the bipolar transistor. Figure 10 shows a peripheral circuit. VIN Pch Cb 2200 pF IPK Rb EXT 1 k Nch Figure 10 External Transistor Periphery 1 k is recommended for Rb. Actually, calculate the necessary base current (Ib) from hFE of the bipolar transistor as follows and select an Rb value lower than this. Ib = Rb = IPK hFE VIN - 0.7 Ib - 0.4 IEXTH A small Rb increases the output current, but the efficiency decreases. Actually, a pulsating current flows and a voltage drop occurs due to the wiring capacitance. Determine the optimum value by experiment. A speed-up capacitor (Cb) connected in parallel with Rb resistance as shown in Figure 10 decreases the switching loss and improves the efficiency. Select Cb by observing the following equation. Cb 1 2 * Rb * fOSC * 0.7 However, in practice, the optimum Cb value also varies depending on the characteristics of the bipolar transistor employed. Therefore, determine the optimum value of Cb by experiment. Seiko Instruments Inc. 17 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 4-2. Enhancement MOS FET type Use an Nch power MOS FET. For high efficiency, using a MOS FET with a low ON resistance (RON) and small input capacitance (CISS) is ideal, however, ON resistance and input capacitance generally share a trade-off relationship. The ON resistance is efficient in a range in which the output current is relatively great during low-frequency switching, and the input capacitance is efficient in a range in which the output current is middling during high-frequency switching. Select a MOS FET whose ON resistance and input capacitance are optimal depending on the usage conditions. The input voltage (VIN) is supplied for the gate voltage of the MOS FET, so select a MOS FET with a gate withstanding voltage that is equal to the maximum usage value of the input voltage or higher and a drain withstanding voltage that is equal to the amount of the output voltage (VOUT) and diode voltage (VD) or higher. If a MOS FET with a threshold that is near the UVLO detection voltage is used, a large current may flow, stopping the output voltage from rising and possibly generating heat in the worst case. Select a MOS FET with a threshold that is sufficiently lower than the UVLO detection voltage value. 18 Seiko Instruments Inc. STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 5. Oscillation frequency and maximum duty ratio setting resistors (ROSC, RDuty) With the S-8337/8338 Series, the oscillation frequency can be set in a range of 286 kHz to 1.133 MHz using external resistance. Connect a resistor across the ROSC and VSS pins. Select the resistor by using the following equation and referring to Figure 11. However, the following equation and figure assume that the resistance value is the desired value and show the theoretical values when the IC is in the typical conditions. Note that fluctuations of resistance and IC are not considered. 3 1400 140 * 10 fOSC [kHz] 1200 fOSC [kHz] ROSC [k] 1000 800 600 400 200 0 0 400 200 600 ROSC [k] Figure 11 ROSC vs. fOSC With the S-8337 Series, the maximum duty ratio can be set in a range of 47% to 88.5% by an external resistor. Connect the resistor across the RDuty and VSS pins. Select the resistance by using the following equation and referring to Figure 12. The maximum duty ratio fluctuates according to the oscillation frequency. If the value of ROSC is changed, therefore, be sure to change the value of RDuty so that it is always in proportion to ROSC. However, the following equation and figure assume that the resistance value is the desired value and show the theoretical values when the IC is in the typical conditions. Note that fluctuations of resistance and IC are not considered. (94.5 - MaxDuty) 11.5 100 90 MaxDuty [%] RDuty ROSC 80 70 60 50 40 0 1 2 3 4 5 RDuty/ROSC Figure 12 RDuty/ROSC vs. MaxDuty Connect resistors ROSC and RDuty as close to the IC as possible. Seiko Instruments Inc. 19 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 6. Short-circuit protection delay time setting capacitor (CSP) With the S-8337/8338 Series, the short-circuit protection delay time can be set to any value by an external capacitor. Connect the capacitor across the CSP and VSS pins. Select the capacitance by using the following equation and referring to Figure 13. However, the following equation and figure assume that the capacitor value is the desired value and show the theoretical values when the IC is in the typical conditions. Note that fluctuations of capacitor and IC are not considered. tPRO [ms] * 2 * 10-3 1.0 120 100 tPRO [ms] CSP [F] 80 60 40 20 0 0 0.05 0.10 0.15 0.20 0.25 CSP [F] Figure 13 CSP vs. tPRO 7. Output voltage setting resistors (RFB1, RBF2) With the S-8337/8338 Series, the output voltage can be set to any value by external divider resistors. Connect the divider resistors across the VOUT and VSS pins. Because VFB = 1 V, the output voltage can be calculated by this equation. VOUT = (RFB1 + RFB2) RFB2 Connect divider resistors RFB1 and RFB2 as close to the IC to minimize effects from of noise. If noise does have an effect, adjust the values of RFB1 and RFB2 so that RFB1 + RFB2 < 100 k. CFB connected in parallel with RFB1 is a capacitor for phase compensation. Select the optimum value of this capacitor at which the stable operation can be ensured from the values of the inductor and output capacitor. 8. Phase compensation setting resistor and capacitor (RZ, CZ) The S-8337/8338 Series needs appropriate compensation for the voltage feedback loop to prevent excessive output ripple and unstable operation from deteriorating the efficiency. This compensation is implemented by connecting RZ and CZ in series across the CC and VSS pins. RZ sets the high-frequency gain for a high-speed transient response. CZ sets the pole and zero of the error amplifier and keeps the loop stable. Adjust RZ and CZ, taking into consideration conditions such as the inductor, output capacitor, and load current, so that the optimum transient characteristics can be obtained. 20 Seiko Instruments Inc. STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Standard Circuits SD L VOUT RDuty (S-8337) VIN UVLO M1 CIN ROSC CFB RFB1 Oscillator Maximum duty circuit + CL - EXT PWM comparator + Timer latch short-circuit protection circuit 0.1 F VSS CSP Error amplifier - ROSC RDuty FB Reference voltage (1.0 V) soft-start circuit RFB2 CC RZ CZ Ground point Figure 14 Standard Circuit (S-8337 Series) SD L VOUT ON/OFF (S-8338) VIN UVLO M1 CIN ROSC + PWM - comparator EXT + Timer latch short-circuit protection circuit 0.1 F VSS CSP CFB RFB1 Oscillator Maximum duty circuit Error amplifier - Reference voltage (1.0 V) soft-start circuit CL ROSC FB RFB2 CC RZ CZ Ground point Figure 15 Standard Circuit (S-8338 Series) Caution The above connection diagram and constant will not guarantee successful operation. Perform thorough evaluation using the actual application to set the constant. Seiko Instruments Inc. 21 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Power Dissipation of Package 600 8-Pin TSSOP 8-Pin SON(A) 400 Power Dissipation PD (mW) 200 0 0 50 100 150 Ambient Temperature Ta (C) Figure 16 Power Dissipation of Package (Before Mounting) Precaution * Mount external capacitors, diodes, and inductor as close as possible to the IC. * Characteristics ripple voltage and spike noise occur in IC containing switching regulators. Moreover rush current flows at the time of a power supply injection. Because these largely depend on the inductor, the capacitor and impedance of power supply used, fully check them using an actually mounted model. * Make sure the dissipation of the switching transistor (especially at a high temperature) does not exceed the allowable power dissipation of the package. * The performance of a switching regulator varies depending on the design of the PCB patterns, peripheral circuits, and external parts. Thoroughly test all settings with your device. * This IC builds in soft start function, starts reference voltage gradually, and it is controlled so that FB pin voltage and reference voltage become this potential. Therefore, keep in mind that it will be in a maximum duty state according to the factor of IC exterior if FB pin voltage is held less than reference voltage. * Although the IC contains a static electricity protection circuit, static electricity or voltage that exceeds the limit of the protection circuit should not be applied. * Seiko Instruments Inc. assumes no responsibility for the way in which this IC is used on products created using this IC or for the specifications of that product, nor does Seiko Instruments Inc. assume any responsibility for any infringement of patents or copyrights by products that include this IC either in Japan or in other countries. 22 Seiko Instruments Inc. STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Example of Major Temperature Characteristics (Ta = -40 to 85C) 700 600 500 ISS1 ISS1 vs. Ta (VIN = 3.3 V) fOSC = 1133 kHz (ROSC = 120 k) fOSC = 700 kHz (ROSC = 200 k) 400 [A] 300 200 fOSC = 286 kHz (ROSC = 510 k) 100 0 -40 -20 0 20 40 Ta [C] 60 80 100 IEXTH vs. Ta (VIN = 3.3 V) -200 f OSC = 700 kHz, MaxDuty = 77% (ROSC = 200 k, RDuty = 300 k) -180 -160 -140 IEXTH -120 -100 [mA] -80 -60 -40 -20 0 -40 -20 0 20 40 60 80 100 Ta [C] 0.10 0.08 0.06 0.04 IFB 0.02 0 [A] -0.02 -0.04 -0.06 -0.08 -0.10 -40 100 90 80 70 MaxDuty 60 50 [%] 40 30 20 10 0 -40 IFB vs. Ta (VIN = 3.3 V) 1.0 0.9 0.8 0.7 ISSS 0.6 0.5 [A] 0.4 0.3 0.2 0.1 0 -40 ISSS vs. Ta (VIN = 3.3 V) fOSC = 700 kHz (ROSC = 200 k) -20 0 20 40 Ta [C] 60 80 100 IEXTL vs. Ta (VIN = 3.3 V) 200 f OSC = 700 kHz, MaxDuty = 77% (ROSC = 200 k, RDuty = 300 k) 180 160 140 IEXTL 120 100 [mA] 80 60 40 20 0 -40 -20 0 20 40 60 80 100 Ta [C] fOSC vs. Ta (VIN = 3.3 V) 1400 fOSC = 1133 kHz (ROSC = 120 k) 1200 1000 fOSC = 700 kHz (ROSC = 200 k) fOSC 800 [kHz] 600 fOSC = 286 kHz (ROSC = 510 k) 400 200 -20 0 20 40 Ta [C] 60 80 0 -40 100 MaxDuty vs. Ta (VIN = 3.3 V) -20 0 tSS 15.0 [ms] 80 100 80 100 tSS = 20 ms 20.0 MaxDuty = 47% (ROSC = 200 k, RDuty = 820 k) 60 tSS vs. Ta (VIN = 3.3 V) 25.0 MaxDuty = 88.5% (ROSC = 200 k, RDuty = 100 k) MaxDuty = 77% (ROSC = 200 k, RDuty = 300 k) 20 40 Ta [C] tSS = 10 ms 10.0 5.0 -20 0 20 40 Ta [C] 60 80 100 Seiko Instruments Inc. 0 -40 -20 0 20 40 Ta [C] 60 23 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series tPRO vs. Ta (VIN = 3.3 V) 70.0 tPRO = 50 ms (CSP = 0.1 F) 60.0 VUVLO vs. Ta 2.5 2.0 VUVLO = 2.3 V 50.0 tPRO 40.0 VUVLO 1.5 [ms] 30.0 [V] VUVLO = 1.5 V 1.0 20.0 0.5 10.0 0 -40 -20 0 20 40 Ta [C] 60 80 100 0 -40 100 -100 -90 -80 -70 ICCH -60 -50 [A] -40 -30 -20 -10 0 -40 VUVLOHYS vs. Ta 0.35 0.30 VUVLOHYS = 0.3 V 0.25 VUVLOHYS 0.20 [V] 0.15 0.10 VUVLOHYS = 0.1 V 0.05 0 -40 ICCL [A] VSH [V] 24 100 90 80 70 60 50 40 30 20 10 0 -40 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -40 -20 0 20 40 Ta [C] 60 80 ICCL vs. Ta (VIN = 3.3 V) -20 0 20 40 Ta [C] 60 80 100 80 100 80 100 80 100 ICCH vs. Ta (VIN = 3.3 V) -20 0 20 40 Ta [C] 60 VRTLT vs. Ta (VIN = 3.3 V) 1.2 1.0 0.8 VRTLT [V] 0.6 0.4 0.2 -20 0 20 40 Ta [C] 60 80 100 0 -40 100 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -40 VSH vs. Ta (VIN = 3.3 V) VSL [V] -20 0 20 40 Ta [C] 60 80 Seiko Instruments Inc. -20 0 20 40 Ta [C] 60 VSL vs. Ta (VIN = 3.3 V) -20 0 20 40 Ta [C] 60 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series ISH vs. Ta (VIN = 3.3 V) 0.1 ISH [A] ISL 0 -0.1 -40 0 [A] -20 0 20 40 Ta [C] 60 ISL vs. Ta (VIN = 3.3 V) 0.1 80 100 -0.1 -40 Seiko Instruments Inc. -20 0 20 40 Ta [C] 60 80 100 25 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Example of Major Power Supply Dependence Characteristics (Ta = 25C) ISS1 vs. VIN 1200 fOSC = 1133 kHz 1000 (ROSC = 120 k) fOSC = 700 kHz 800 (ROSC = 200 k) ISS1 [A] 600 400 200 fOSC = 286 kHz (ROSC = 510 k) 0 0 1 2 5 6 7 1 2 3 4 VIN [V] 5 6 0 1 2 3 4 VIN [V] 5 6 7 IEXTL vs. VIN f OSC = 700 kHz, MaxDuty = 77% (ROSC = 200 k, RDuty = 300 k) 0 7 IFB vs. VIN 0.10 0.08 0.06 0.04 IFB 0.02 0 [A] -0.02 -0.04 -0.06 -0.08 -0.10 fOSC = 700 kHz (ROSC = 200 k) 200 180 160 140 IEXTL 120 100 [mA] 80 60 40 20 0 f OSC = 700 kHz, MaxDuty = 77% (ROSC = 200 k, RDuty = 300 k) 0 1 2 3 4 VIN [V] 5 6 7 5 6 7 fOSC vs. VIN 1400 fOSC = 1133 kHz (ROSC = 120 k) 1200 1000 fOSC = 700 kHz (ROSC = 200 k) fOSC 800 [kHz] 600 fOSC = 286 kHz (ROSC = 510 k) 400 200 0 0 1 2 3 4 VIN [V] 5 6 0 7 MaxDuty vs. VIN 100 90 80 70 MaxDuty 60 50 [%] 40 30 20 10 0 1 2 3 4 VIN [V] tSS vs. VIN 25.0 tSS = 20 ms 20.0 MaxDuty = 88.5% (ROSC = 200 k, RDuty = 100 k) MaxDuty = 77% (ROSC = 200 k, RDuty = 300 k) tSS 15.0 [ms] MaxDuty = 47% (ROSC = 200 k, RDuty = 820 k) tSS = 10 ms 10.0 5.0 0 0 26 3 4 VIN [V] IEXTH vs. VIN -200 -180 -160 -140 IEXTH -120 -100 [mA] -80 -60 -40 -20 0 ISSS vs. VIN 1.0 0.9 0.8 0.7 ISSS 0.6 0.5 [A] 0.4 0.3 0.2 0.1 0 1 2 3 4 VIN [V] 5 6 7 Seiko Instruments Inc. 0 1 2 3 4 VIN [V] 5 6 7 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series tPRO vs. VIN 70.0 tPRO = 50 ms (CSP = 0.1 F) 60.0 50.0 tPRO 40.0 [ms] 30.0 20.0 10.0 0 0 ICCL [A] [V] 2 3 4 VIN [V] 5 6 0 7 ICCL vs. VIN 100 90 80 70 60 50 40 30 20 10 0 VSH [V] 0 VSL 1 1 2 3 4 VIN [V] 5 6 ICCH vs. VIN -100 -90 -80 -70 ICCH -60 -50 [A] -40 -30 -20 -10 0 1 2 0 1 2 VSL vs. VIN 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 5 6 7 5 6 7 5 6 7 VSH vs. VIN 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 7 3 4 VIN [V] 3 4 VIN [V] ISH vs. VIN 0.1 ISH 0 [A] -0.1 0 1 2 3 4 VIN [V] 5 6 7 5 6 7 0 1 2 3 4 VIN [V] ISL vs. VIN 0.1 ISL [A] 0 -0.1 0 1 2 3 4 VIN [V] Seiko Instruments Inc. 27 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Example of External Parts Dependence Characteristics fOSC vs. ROSC (VIN = 3.3 V) 1600 Ta = -40C Ta = 25C Ta = 85C 1400 1200 fOSC 1000 [kHz] 800 600 400 200 200 0 0 100 200 300 400 ROSC [k] 500 Ta = -40C Ta = 25C Ta = 85C 0 0.5 1 1.5 2 2.5 3 3.5 4 RDuty/ROSC 0 600 MaxDuty vs. RDuty/ROSC (ROSC = 200 k, VIN = 3.3 V) 100 90 80 70 MaxDuty 60 50 [%] 40 30 20 10 0 300 400 ROSC [k] 500 300 300 250 250 tPRO 600 Ta = -40C Ta = 25C Ta = 85C 4.5 5 tPRO vs. CSP (VIN = 5.0 V) 350 200 200 0 0.5 1 1.5 2 2.5 3 3.5 4 RDuty/ROSC 4.5 5 [ms] 150 100 MaxDuty vs. RDuty/ROSC (ROSC = 200 k, VIN = 5.0 V) 100 90 80 70 MaxDuty 60 50 [%] 40 30 20 10 0 tPRO vs. CSP (VIN = 3.3 V) 350 200 [ms] 150 100 Ta = -40C Ta = 25C Ta = 85C 50 0 0 28 1000 400 0 tPRO 1200 [kHz] 600 Ta = -40C Ta = 25C Ta = 85C 1400 fOSC 800 fOSC vs. ROSC (VIN = 5.0 V) 1600 0.1 0.2 0.3 CSP [F] 0.4 100 0.5 Seiko Instruments Inc. Ta = -40C Ta = 25C Ta = 85C 50 0 0 0.1 0.2 0.3 CSP [F] 0.4 0.5 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Examples of Transient Response Characteristics 1. Powering ON (VOUT = 9.2 V, VIN = 0 V3.3 V, Ta = 25C) 1-1. fOSC = 1133 kHz, IOUT = 0 mA, tSS = 10 ms VIN [V] 4 1-2. fOSC = 1133 kHz, IOUT = 100 mA, tSS = 10 ms 12 12 8 VOUT 8 VOUT 4 [V] 4 [V] 0 2 VIN [V] 0 0 5 10 time [ms] 15 4 -5 5 10 time [ms] 15 20 12 12 8 VOUT 8 VOUT 4 [V] 4 [V] 0 2 VIN [V] 4 0 2 0 -5 0 5 10 time [ms] 15 20 1-5. fOSC = 286 kHz, IOUT = 0 mA, tSS = 10 ms [V] 0 1-4. fOSC = 700 kHz, IOUT = 100 mA, tSS = 10 ms 0 VIN 2 20 1-3. fOSC = 700 kHz, IOUT = 0 mA, tSS = 10 ms [V] 0 0 -5 VIN 4 4 -5 0 5 10 time [ms] 15 20 1-6. fOSC = 286 kHz, IOUT = 100 mA, tSS = 10 ms 12 12 8 VOUT 8 VOUT 4 [V] 4 [V] 0 2 VIN [V] 0 4 0 2 0 -5 0 5 10 time [ms] 15 20 Seiko Instruments Inc. -5 0 5 10 time [ms] 15 20 29 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 2. Responses of shutdown pin (VOUT = 9.2 V, VON/OFF = 0 V3.3 V) 2-1. fOSC = 1133 kHz, IOUT = 0 mA, tSS = 10 ms VON/OFF [V] 4 2-2. fOSC = 1133 kHz, IOUT = 100 mA, tSS = 10 ms 12 12 8 VOUT 8 VOUT 4 [V] 4 [V] 0 2 VON/OFF [V] 0 0 5 10 time [ms] 15 4 -5 15 20 12 8 VOUT 8 VOUT 4 [V] 4 [V] 2 VON/OFF [V] 4 0 2 0 0 5 10 time [ms] 15 20 2-5. fOSC = 286 kHz, IOUT = 0 mA, tSS = 10 ms 4 -5 0 5 10 time [ms] 15 20 2-6. fOSC = 286 kHz, IOUT = 100 mA, tSS = 10 ms 12 12 8 VOUT 8 VOUT 4 [V] 4 [V] 0 2 VON/OFF [V] 0 4 0 2 0 -5 30 5 10 time [ms] 2-4. fOSC = 700 kHz, IOUT = 100 mA, tSS = 10 ms 0 -5 [V] 0 12 0 VON/OFF 2 20 2-3. fOSC = 700 kHz, IOUT = 0 mA, tSS = 10 ms [V] 0 0 -5 VON/OFF 4 0 5 10 time [ms] 15 20 Seiko Instruments Inc. -5 0 5 10 time [ms] 15 20 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 3. Load fluctuations (VOUT = 9.2 V, VIN = 3.3 V, Ta = 25C, RZ = 200 k, CZ = 0.01 F) 3-1. fOSC = 1133 kHz, IOUT = 0.1 mA100 mA 3-2. fOSC = 1133 kHz, IOUT = 100 mA0.1 mA 10.0 IOUT IOUT 10.0 100 mA 9.8 100 mA 9.8 0.1 mA 9.6 0.1 mA 9.6 9.4 VOUT 9.2 [0.2 V/div] 9.4 VOUT 9.2 [0.2 V/div] 9.0 -20 -10 0 time [ms] 9.0 8.8 20 10 3-3. fOSC = 700 kHz, IOUT = 0.1 mA100 mA -10 0 time [ms] 10 3-4. fOSC = 700 kHz, IOUT = 100 mA0.1 mA 10.0 IOUT -20 IOUT 8.8 20 10.0 100 mA 9.8 100 mA 9.8 0.1 mA 9.6 0.1 mA 9.6 9.4 VOUT 9.2 [0.2 V/div] -20 9.0 -10 0 time [ms] 3-5. fOSC = 286 kHz, IOUT = 0.1 mA100 mA 9.2 [0.2 V/div] 9.0 8.8 20 10 -20 -10 0 time [ms] 10 3-6. fOSC = 286 kHz, IOUT = 100 mA0.1 mA 10.0 IOUT 9.4 VOUT IOUT 8.8 20 10.0 100 mA 9.8 100 mA 9.8 0.1 mA 9.6 0.1 mA 9.6 9.4 VOUT 9.2 [0.2 V/div] -20 9.0 -10 0 time [ms] 10 9.4 VOUT 9.2 [0.2 V/div] 8.8 20 Seiko Instruments Inc. 9.0 -20 -10 0 time [ms] 10 8.8 20 31 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 4. Input voltage fluctuations (VOUT = 9.2 V, IOUT = 100 mA, RZ = 200 k, CZ = 0.01 F) 4-1. fOSC = 1133 kHz, VIN = 2.7 V3.7 V 4-2. fOSC = 1133 kHz, VIN = 3.7 V2.7 V 4.0 4.0 VIN 3.5 VIN 3.5 [V] 3.0 [V] 3.0 2.5 -20 9.30 -10 0 time [ms] 10 2.5 9.25 VOUT 9.25 VOUT 9.20 [V] 9.20 [V] 9.15 9.15 20 4-3. fOSC = 700 kHz, VIN = 2.7 V3.7 V -20 4.0 VIN 3.5 VIN 3.5 [V] 3.0 [V] 3.0 -20 9.30 -10 0 time [ms] 10 9.25 VOUT 9.15 9.15 20 -20 VIN 3.5 [V] 3.0 32 -10 0 time [ms] 10 20 4-6. fOSC = 286 kHz, VIN = 3.7 V2.7 V [V] 3.0 9.30 10 9.30 9.20 [V] VIN 3.5 0 time [ms] 20 9.25 VOUT 4.0 -10 10 2.5 4.0 -20 0 time [ms] 9.20 [V] 4-5. fOSC = 286 kHz, VIN = 2.7 V3.7 V 2.5 -10 4-4. fOSC = 700 kHz, VIN = 3.7 V2.7 V 4.0 2.5 9.30 2.5 9.30 9.25 VOUT 9.25 VOUT 9.20 [V] 9.20 [V] 9.15 9.15 20 Seiko Instruments Inc. -20 -10 0 time [ms] 10 20 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Reference Data 1. Reference data for external parts Element Name Inductor Diode Output capacitor Transistor *1. DCR : *2. IMAX : *3. VF : *4. IF : *5. VDSS : *6. VGSS : *7. Ciss : *8. RDS(ON) *9. VGS : *10. ID : Table 8 Properties of External Parts Product Name Manufacture Characteristics 4.7 H, DCR*1 = 206 m, IMAX*2 = 0.9 A, LDR655312T TDK Corporation Height = 1.2 mm RB491D VF*3 = 0.45 V, IF*4 = 1.0 A Rohm Co., Ltd. 16 V, 10 F VDSS*5 = 20 V, VGSS*6 = 10 V, Ciss*7 = 280 pF, MCH3406 Sanyo Electric Co., Ltd. RDS(ON)*8 = 82 m max. (VGS*9 = 2.5 V, ID*10 = 1 A) DC resistance Maximum allowable current Forward voltage Forward current Drain to source voltage (When between gate and source short circuits) Gate to source voltage (When between drain and source short circuits) Input capacitance : Drain to source on resistance Gate to source voltage Drain current Caution The values shown in the characteristics column of Table 8 above are based on the materials provided by each manufacturer. However, consider the characteristics of the original materials when using the above products. Seiko Instruments Inc. 33 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 2. Reference data (1) The data of (a) output current (IOUT) vs. efficiency () characteristics and (b) output current (IOUT) vs. output voltage (VOUT) characteristics is shown below. 2-1. VOUT = 13.1 V (RFB1 = 7.5 k, RFB2 = 620 ) (1) fOSC = 1133 kHz, MaxDuty = 77 % (ROSC = 120 k, RDuty = 180 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 50 [%] 40 30 20 10 0 0.01 13.20 13.15 13.10 VOUT 13.05 [V] 13.00 VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 12.95 12.90 0.01 VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 100 1000 100 1000 (2) fOSC = 700 kHz, MaxDuty = 77 % (ROSC = 200 k, RDuty = 300 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 [%] 50 40 30 20 10 0 0.01 13.20 13.15 13.10 VOUT 13.05 [V] 13.00 VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 12.95 12.90 0.01 VIN = 5.0 V 0.1 1 10 IOUT [mA] (3) fOSC = 286 kHz, MaxDuty = 77 % (ROSC = 510 k, RDuty = 750 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 50 [%] 40 30 20 10 0 0.01 13.20 34 13.15 13.10 VOUT 13.05 [V] 13.00 VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 12.95 12.90 0.01 Seiko Instruments Inc. VIN = 5.0 V 0.1 1 10 IOUT [mA] STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 2-2. VOUT = 9.2 V (RFB1 = 8.2 k, RFB2 = 1.0 k) (1) fOSC = 1133 kHz, MaxDuty = 77 % (ROSC = 120 k, RDuty = 180 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 50 [%] 40 30 20 10 0 0.01 9.30 9.25 VOUT [V] 9.20 9.15 9.10 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 9.05 9.00 0.01 1000 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 100 1000 100 1000 (2) fOSC = 700 kHz, MaxDuty = 77 % (ROSC = 200 k, RDuty = 300 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 50 [%] 40 30 20 10 0 0.01 9.30 9.25 VOUT [V] 9.20 9.15 9.10 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 9.05 9.00 0.01 1000 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] (3) fOSC = 286 kHz, MaxDuty = 77 % (ROSC = 510 k, RDuty = 750 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 50 [%] 40 30 20 10 0 0.01 9.30 9.25 VOUT [V] 9.20 9.15 9.10 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 Seiko Instruments Inc. 9.05 9.00 0.01 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] 35 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 2-3. VOUT = 6.1 V (RFB1 = 5.1 k, RFB2 = 1.0 k) (1) fOSC = 1133 kHz, MaxDuty = 77 % (ROSC = 120 k, RDuty = 180 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 50 [%] 40 30 20 10 0 0.01 6.20 6.15 VOUT [V] 6.10 6.05 6.00 VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] 100 5.95 5.90 0.01 1000 VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] 100 1000 100 1000 100 1000 (2) fOSC = 700 kHz, MaxDuty = 77 % (ROSC = 200 k, RDuty = 300 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 50 [%] 40 30 20 10 0 0.01 6.20 6.15 6.10 VOUT 6.05 [V] 6.00 VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] 100 5.95 5.90 0.01 1000 VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] (3) fOSC = 286 kHz, MaxDuty = 77 % (ROSC = 510 k, RDuty = 750 k) (a) IOUT vs. (b) IOUT vs. VOUT 100 90 80 70 60 [%] 50 40 30 20 10 0 0.01 6.20 36 6.15 VOUT [V] 6.10 6.05 6.00 VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] 100 1000 Seiko Instruments Inc. 5.95 5.90 0.01 VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 3. Reference data (2) The data of output current (IOUT) vs. ripple voltage (Vr) characteristics is shown below. 3-1. VOUT = 13.1 V (RFB1 = 7.5 k, RFB2 = 620 ) (1) fOSC = 1133 kHz, MaxDuty = 77 % (ROSC = 120 k, RDuty = 180 k) 100 90 80 70 60 Vr 50 [mV] 40 30 20 10 0 0.01 VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 (2) fOSC = 700 kHz, MaxDuty = 77 % (ROSC = 200 k, RDuty = 300 k) 100 90 80 70 60 Vr 50 [mV] 40 30 20 10 0 0.01 VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 (3) fOSC = 286 kHz, MaxDuty = 77 % (ROSC = 510 k, RDuty = 750 k) 100 90 80 70 60 Vr 50 [mV] 40 30 20 10 0 0.01 VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 3-2. VOUT = 9.2 V (RFB1 = 8.2 k, RFB2 = 1.0 k) (1) fOSC = 1133 kHz, MaxDuty = 77 % (ROSC = 120 k, RDuty = 180 k) 100 90 80 70 60 Vr 50 [mV] 40 30 20 10 0 0.01 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 (2) fOSC = 700 kHz, MaxDuty = 77 % (ROSC = 200 k, RDuty = 300 k) 100 90 80 70 60 Vr 50 [mV] 40 30 20 10 0 0.01 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 (3) fOSC = 286 kHz, MaxDuty = 77 % (ROSC = 510 k, RDuty = 750 k) 100 90 80 70 60 Vr 50 [mV] 40 30 20 10 0 0.01 VIN = 3.3 V VIN = 5.0 V 0.1 1 10 IOUT [mA] 100 1000 Seiko Instruments Inc. 37 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series 3-3. VOUT = 6.1 V (RFB1 = 5.1 k, RFB2 = 1.0 k) (1) fOSC = 1133 kHz, MaxDuty = 77 % (ROSC = 120 k, RDuty = 180 k) 100 90 80 70 Vr 60 50 [mV] 40 30 20 10 0 0.01 VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] 100 1000 (2) fOSC = 700 kHz, MaxDuty = 77 % (ROSC = 200 k, RDuty = 300 k) 100 90 80 70 Vr 60 50 [mV] 40 30 20 10 0 0.01 (3) fOSC = 286 kHz, MaxDuty = 77 % (ROSC = 510 k, RDuty = 750 k) 100 90 80 70 Vr 60 50 [mV] 40 30 20 10 0 0.01 38 VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] 100 1000 Seiko Instruments Inc. VIN = 1.8 V VIN = 3.3 V 0.1 1 10 IOUT [mA] 100 1000 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series Marking Specification (1) 8-Pin SON(A) 8-Pin SON(A) Top view 1 (1) ~ (3) (4) ~ (8) Product code (Refer to Product name vs. Product code) Lot number 8 (1) (2) (3) (4) (5) (6) (7) (8) 2 5 Product name vs. Product code (a) S-8337Series Product name S-8337AAAA-P8T1 S-8337AAAB-P8T1 S-8337AAAC-P8T1 S-8337AABA-P8T1 S-8337AABB-P8T1 S-8337AABC-P8T1 S-8337AACA-P8T1 S-8337AACB-P8T1 S-8337AACC-P8T1 S-8337AADA-P8T1 S-8337AADB-P8T1 S-8337AADC-P8T1 S-8337AAEA-P8T1 S-8337AAEB-P8T1 S-8337AAEC-P8T1 S-8337AAFA-P8T1 S-8337AAFB-P8T1 S-8337AAFC-P8T1 S-8337AAGA-P8T1 S-8337AAGB-P8T1 S-8337AAGC-P8T1 S-8337AAHA-P8T1 S-8337AAHB-P8T1 S-8337AAHC-P8T1 S-8337AAIA-P8T1 S-8337AAIB-P8T1 S-8337AAIC-P8T1 S-8337ABAA-P8T1 S-8337ABAB-P8T1 S-8337ABAC-P8T1 S-8337ABBA-P8T1 S-8337ABBB-P8T1 S-8337ABBC-P8T1 S-8337ABCA-P8T1 S-8337ABCB-P8T1 S-8337ABCC-P8T1 S-8337ABDA-P8T1 S-8337ABDB-P8T1 S-8337ABDC-P8T1 S-8337ABEA-P8T1 S-8337ABEB-P8T1 (1) O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O Product code (2) (3) B A B B B 2 B C B D B E B F B G B H B I B J B K B L B M B N B O B P B Q B R B S B T B U B V B W B X B Y B Z D A D B D 2 D C D D D E D F D G D H D I D J D K D L D M Product name S-8337ABEC-P8T1 S-8337ABFA-P8T1 S-8337ABFB-P8T1 S-8337ABFC-P8T1 S-8337ABGA-P8T1 S-8337ABGB-P8T1 S-8337ABGC-P8T1 S-8337ABHA-P8T1 S-8337ABHB-P8T1 S-8337ABHC-P8T1 S-8337ABIA-P8T1 S-8337ABIB-P8T1 S-8337ABIC-P8T1 S-8337ACAA-P8T1 S-8337ACAB-P8T1 S-8337ACAC-P8T1 S-8337ACBA-P8T1 S-8337ACBB-P8T1 S-8337ACBC-P8T1 S-8337ACCA-P8T1 S-8337ACCB-P8T1 S-8337ACCC-P8T1 S-8337ACDA-P8T1 S-8337ACDB-P8T1 S-8337ACDC-P8T1 S-8337ACEA-P8T1 S-8337ACEB-P8T1 S-8337ACEC-P8T1 S-8337ACFA-P8T1 S-8337ACFB-P8T1 S-8337ACFC-P8T1 S-8337ACGA-P8T1 S-8337ACGB-P8T1 S-8337ACGC-P8T1 S-8337ACHA-P8T1 S-8337ACHB-P8T1 S-8337ACHC-P8T1 S-8337ACIA-P8T1 S-8337ACIB-P8T1 S-8337ACIC-P8T1 Seiko Instruments Inc. Product code (1) (2) (3) O D N O D O O D P O D Q O D R O D S O D T O D U O D V O D W O D X O D Y O D Z O J A O J B O J 2 O J C O J D O J E O J F O J G O J H O J I O J J O J K O J L O J M O J N O J O O J P O J Q O J R O J S O J T O J U O J V O J W O J X O J Y O J Z 39 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series (b) S-8338 Series Product name S-8338AAAA-P8T1 S-8338AAAB-P8T1 S-8338AAAC-P8T1 S-8338AABA-P8T1 S-8338AABB-P8T1 S-8338AABC-P8T1 S-8338AACA-P8T1 S-8338AACB-P8T1 S-8338AACC-P8T1 S-8338AADA-P8T1 S-8338AADB-P8T1 S-8338AADC-P8T1 S-8338AAEA-P8T1 S-8338AAEB-P8T1 S-8338AAEC-P8T1 S-8338AAFA-P8T1 S-8338AAFB-P8T1 S-8338AAFC-P8T1 S-8338AAGA-P8T1 S-8338AAGB-P8T1 S-8338AAGC-P8T1 S-8338AAHA-P8T1 S-8338AAHB-P8T1 S-8338AAHC-P8T1 S-8338AAIA-P8T1 S-8338AAIB-P8T1 S-8338AAIC-P8T1 S-8338ABAA-P8T1 S-8338ABAB-P8T1 S-8338ABAC-P8T1 S-8338ABBA-P8T1 S-8338ABBB-P8T1 S-8338ABBC-P8T1 S-8338ABCA-P8T1 S-8338ABCB-P8T1 S-8338ABCC-P8T1 S-8338ABDA-P8T1 S-8338ABDB-P8T1 S-8338ABDC-P8T1 S-8338ABEA-P8T1 S-8338ABEB-P8T1 40 (1) O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O Product code (2) (3) C A C B C 2 C C C D C E C F C G C H C I C J C K C L C M C N C O C P C Q C R C S C T C U C V C W C X C Y C Z I A I B I 2 I C I D I E I F I G I H I I I J I K I L I M Product name S-8338ABEC-P8T1 S-8338ABFA-P8T1 S-8338ABFB-P8T1 S-8338ABFC-P8T1 S-8338ABGA-P8T1 S-8338ABGB-P8T1 S-8338ABGC-P8T1 S-8338ABHA-P8T1 S-8338ABHB-P8T1 S-8338ABHC-P8T1 S-8338ABIA-P8T1 S-8338ABIB-P8T1 S-8338ABIC-P8T1 S-8338ACAA-P8T1 S-8338ACAB-P8T1 S-8338ACAC-P8T1 S-8338ACBA-P8T1 S-8338ACBB-P8T1 S-8338ACBC-P8T1 S-8338ACCA-P8T1 S-8338ACCB-P8T1 S-8338ACCC-P8T1 S-8338ACDA-P8T1 S-8338ACDB-P8T1 S-8338ACDC-P8T1 S-8338ACEA-P8T1 S-8338ACEB-P8T1 S-8338ACEC-P8T1 S-8338ACFA-P8T1 S-8338ACFB-P8T1 S-8338ACFC-P8T1 S-8338ACGA-P8T1 S-8338ACGB-P8T1 S-8338ACGC-P8T1 S-8338ACHA-P8T1 S-8338ACHB-P8T1 S-8338ACHC-P8T1 S-8338ACIA-P8T1 S-8338ACIB-P8T1 S-8338ACIC-P8T1 Seiko Instruments Inc. Product code (1) (2) (3) O I N O I O O I P O I Q O I R O I S O I T O I U O I V O I W O I X O I Y O I Z O K A O K B O K 2 O K C O K D O K E O K F O K G O K H O K I O K J O K K O K L O K M O K N O K O O K P O K Q O K R O K S O K T O K U O K V O K W O K X O K Y O K Z STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series (2) 8-Pin TSSOP 8-Pin TSSOP Top view 1 (1) ~ (4) 8 (1) (2) (3) (4) (5) ~ (8) (9) ~ (14) (5) (6) (7) (8) 4 (9) (10) (11) (12) (13) (14) Product name: 8337 or 8338 (Fixed) 8337 indicates S-8337 series. 8338 indicates S-8338 series. Function code (Refer to Product name vs. Function code) Lot number 5 Product name vs. Function code (a) S-8337 Series Product name S-8337AAAA-T8T1 S-8337AAAB-T8T1 S-8337AAAC-T8T1 S-8337AABA-T8T1 S-8337AABB-T8T1 S-8337AABC-T8T1 S-8337AACA-T8T1 S-8337AACB-T8T1 S-8337AACC-T8T1 S-8337AADA-T8T1 S-8337AADB-T8T1 S-8337AADC-T8T1 S-8337AAEA-T8T1 S-8337AAEB-T8T1 S-8337AAEC-T8T1 S-8337AAFA-T8T1 S-8337AAFB-T8T1 S-8337AAFC-T8T1 S-8337AAGA-T8T1 S-8337AAGB-T8T1 S-8337AAGC-T8T1 S-8337AAHA-T8T1 S-8337AAHB-T8T1 S-8337AAHC-T8T1 S-8337AAIA-T8T1 S-8337AAIB-T8T1 S-8337AAIC-T8T1 S-8337ABAA-T8T1 S-8337ABAB-T8T1 S-8337ABAC-T8T1 S-8337ABBA-T8T1 S-8337ABBB-T8T1 S-8337ABBC-T8T1 S-8337ABCA-T8T1 S-8337ABCB-T8T1 S-8337ABCC-T8T1 S-8337ABDA-T8T1 S-8337ABDB-T8T1 S-8337ABDC-T8T1 S-8337ABEA-T8T1 S-8337ABEB-T8T1 (5) A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Function code (6) (7) (8) A A A A A B A A C A B A A B B A B C A C A A C B A C C A D A A D B A D C A E A A E B A E C A F A A F B A F C A G A A G B A G C A H A A H B A H C A I A A I B A I C B A A B A B B A C B B A B B B B B C B C A B C B B C C B D A B D B B D C B E A B E B Product name S-8337ABEC-T8T1 S-8337ABFA-T8T1 S-8337ABFB-T8T1 S-8337ABFC-T8T1 S-8337ABGA-T8T1 S-8337ABGB-T8T1 S-8337ABGC-T8T1 S-8337ABHA-T8T1 S-8337ABHB-T8T1 S-8337ABHC-T8T1 S-8337ABIA-T8T1 S-8337ABIB-T8T1 S-8337ABIC-T8T1 S-8337ACAA-T8T1 S-8337ACAB-T8T1 S-8337ACAC-T8T1 S-8337ACBA-T8T1 S-8337ACBB-T8T1 S-8337ACBC-T8T1 S-8337ACCA-T8T1 S-8337ACCB-T8T1 S-8337ACCC-T8T1 S-8337ACDA-T8T1 S-8337ACDB-T8T1 S-8337ACDC-T8T1 S-8337ACEA-T8T1 S-8337ACEB-T8T1 S-8337ACEC-T8T1 S-8337ACFA-T8T1 S-8337ACFB-T8T1 S-8337ACFC-T8T1 S-8337ACGA-T8T1 S-8337ACGB-T8T1 S-8337ACGC-T8T1 S-8337ACHA-T8T1 S-8337ACHB-T8T1 S-8337ACHC-T8T1 S-8337ACIA-T8T1 S-8337ACIB-T8T1 S-8337ACIC-T8T1 Seiko Instruments Inc. (5) A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Function code (6) (7) B E B F B F B F B G B G B G B H B H B H B I B I B I C A C A C A C B C B C B C C C C C C C D C D C D C E C E C E C F C F C F C G C G C G C H C H C H C I C I C I (8) C A B C A B C A B C A B C A B C A B C A B C A B C A B C A B C A B C A B C A B C 41 STEP-UP, 1.2 MHz HIGH-FREQUENCY, PWM CONTROL SWITCHING REGULATOR CONTROLLERS Rev.2.1_01 S-8337/8338 Series (b) S-8338 Series Product name S-8338AAAA-T8T1 S-8338AAAB-T8T1 S-8338AAAC-T8T1 S-8338AABA-T8T1 S-8338AABB-T8T1 S-8338AABC-T8T1 S-8338AACA-T8T1 S-8338AACB-T8T1 S-8338AACC-T8T1 S-8338AADA-T8T1 S-8338AADB-T8T1 S-8338AADC-T8T1 S-8338AAEA-T8T1 S-8338AAEB-T8T1 S-8338AAEC-T8T1 S-8338AAFA-T8T1 S-8338AAFB-T8T1 S-8338AAFC-T8T1 S-8338AAGA-T8T1 S-8338AAGB-T8T1 S-8338AAGC-T8T1 S-8338AAHA-T8T1 S-8338AAHB-T8T1 S-8338AAHC-T8T1 S-8338AAIA-T8T1 S-8338AAIB-T8T1 S-8338AAIC-T8T1 S-8338ABAA-T8T1 S-8338ABAB-T8T1 S-8338ABAC-T8T1 S-8338ABBA-T8T1 S-8338ABBB-T8T1 S-8338ABBC-T8T1 S-8338ABCA-T8T1 S-8338ABCB-T8T1 S-8338ABCC-T8T1 S-8338ABDA-T8T1 S-8338ABDB-T8T1 S-8338ABDC-T8T1 S-8338ABEA-T8T1 S-8338ABEB-T8T1 42 (5) A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Function code (6) (7) (8) A A A A A B A A C A B A A B B A B C A C A A C B A C C A D A A D B A D C A E A A E B A E C A F A A F B A F C A G A A G B A G C A H A A H B A H C A I A A I B A I C B A A B A B B A C B B A B B B B B C B C A B C B B C C B D A B D B B D C B E A B E B Product name S-8338ABEC-T8T1 S-8338ABFA-T8T1 S-8338ABFB-T8T1 S-8338ABFC-T8T1 S-8338ABGA-T8T1 S-8338ABGB-T8T1 S-8338ABGC-T8T1 S-8338ABHA-T8T1 S-8338ABHB-T8T1 S-8338ABHC-T8T1 S-8338ABIA-T8T1 S-8338ABIB-T8T1 S-8338ABIC-T8T1 S-8338ACAA-T8T1 S-8338ACAB-T8T1 S-8338ACAC-T8T1 S-8338ACBA-T8T1 S-8338ACBB-T8T1 S-8338ACBC-T8T1 S-8338ACCA-T8T1 S-8338ACCB-T8T1 S-8338ACCC-T8T1 S-8338ACDA-T8T1 S-8338ACDB-T8T1 S-8338ACDC-T8T1 S-8338ACEA-T8T1 S-8338ACEB-T8T1 S-8338ACEC-T8T1 S-8338ACFA-T8T1 S-8338ACFB-T8T1 S-8338ACFC-T8T1 S-8338ACGA-T8T1 S-8338ACGB-T8T1 S-8338ACGC-T8T1 S-8338ACHA-T8T1 S-8338ACHB-T8T1 S-8338ACHC-T8T1 S-8338ACIA-T8T1 S-8338ACIB-T8T1 S-8338ACIC-T8T1 Seiko Instruments Inc. (5) A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Function code (6) (7) B E B F B F B F B G B G B G B H B H B H B I B I B I C A C A C A C B C B C B C C C C C C C D C D C D C E C E C E C F C F C F C G C G C G C H C H C H C I C I C I (8) C A B C A B C A B C A B C A B C A B C A B C A B C A B C A B C A B C A B C A B C 2.900.2 0.475typ. 8 5 1 4 +0.1 0.65 0.30 -0.05 (o1.0) No. PN008-A-P-SD-1.1 (2.3) TITLE SON8A-A-PKG Dimensions PN008-A-P-SD-1.1 No. SCALE UNIT mm Seiko Instruments Inc. 4.00.1 2.00.05 1.50.1 o1.550.05 0.20.05 3.30.1 4 1 5 8 o1.050.05 4.00.1 Feed direction No. PN008-A-C-SD-1.1 TITLE SON8A-A-Carrier Tape No. PN008-A-C-SD-1.1 SCALE UNIT mm Seiko Instruments Inc. 11.41.0 (1.2) 3.00.2 9.00.3 Enlarged drawing in the central part No. PN008-A-R-SD-1.1 SON8A-A-Reel TITLE PN008-A-R-SD-1.1 No. SCALE UNIT QTY. mm Seiko Instruments Inc. 3000 +0.3 3.00 -0.2 8 5 1 4 0.170.05 0.20.1 0.65 No. FT008-A-P-SD-1.1 TITLE TSSOP8-E-PKG Dimensions FT008-A-P-SD-1.1 No. SCALE UNIT mm Seiko Instruments Inc. 4.00.1 2.00.05 o1.550.05 0.30.05 +0.1 8.00.1 o1.55 -0.05 (4.4) +0.4 6.6 -0.2 1 8 4 5 Feed direction No. FT008-E-C-SD-1.0 TITLE TSSOP8-E-Carrier Tape FT008-E-C-SD-1.0 No. SCALE UNIT mm Seiko Instruments Inc. 13.41.0 17.51.0 Enlarged drawing in the central part o210.8 20.5 o130.5 No. FT008-E-R-SD-1.0 TSSOP8-E-Reel TITLE No. FT008-E-R-SD-1.0 SCALE QTY. UNIT mm Seiko Instruments Inc. 3,000 * * * * * * The information described herein is subject to change without notice. Seiko Instruments Inc. is not responsible for any problems caused by circuits or diagrams described herein whose related industrial properties, patents, or other rights belong to third parties. The application circuit examples explain typical applications of the products, and do not guarantee the success of any specific mass-production design. When the products described herein are regulated products subject to the Wassenaar Arrangement or other agreements, they may not be exported without authorization from the appropriate governmental authority. Use of the information described herein for other purposes and/or reproduction or copying without the express permission of Seiko Instruments Inc. is strictly prohibited. The products described herein cannot be used as part of any device or equipment affecting the human body, such as exercise equipment, medical equipment, security systems, gas equipment, or any apparatus installed in airplanes and other vehicles, without prior written permission of Seiko Instruments Inc. Although Seiko Instruments Inc. exerts the greatest possible effort to ensure high quality and reliability, the failure or malfunction of semiconductor products may occur. The user of these products should therefore give thorough consideration to safety design, including redundancy, fire-prevention measures, and malfunction prevention, to prevent any accidents, fires, or community damage that may ensue.