LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 LM2734 Thin SOT 1A Load Step-Down DC-DC Regulator Check for Samples: LM2734 FEATURES DESCRIPTION * * * * * The LM2734 regulator is a monolithic, high frequency, PWM step-down DC/DC converter in a 6-pin Thin SOT package. It provides all the active functions to provide local DC/DC conversion with fast transient response and accurate regulation in the smallest possible PCB area. 1 234 * * * * * * * * Thin SOT-6 Package 3.0V to 20V Input Voltage Range 0.8V to 18V Output Voltage Range 1A Output Current 550kHz (LM2734Y) and 1.6MHz (LM2734X) Switching Frequencies 300m NMOS Switch 30nA Shutdown Current 0.8V, 2% Internal Voltage Reference Internal Soft-Start Current-Mode, PWM Operation WEBENCH(R) Online Design Tool Thermal Shutdown LM2734XQ/LM2734YQ are AEC-Q100 Grade 1 Qualified and are Manufactured on an Automotive Grade Flow APPLICATIONS * * * * * * * * Local Point of Load Regulation Core Power in HDDs Set-Top Boxes Battery Powered Devices USB Powered Devices DSL Modems Notebook Computers Automotive With a minimum of external components and online design support through WEBENCH(R), the LM2734 is easy to use. The ability to drive 1A loads with an internal 300m NMOS switch using state-of-the-art 0.5m BiCMOS technology results in the best power density available. The world class control circuitry allows for on-times as low as 13ns, thus supporting exceptionally high frequency conversion over the entire 3V to 20V input operating range down to the minimum output voltage of 0.8V. Switching frequency is internally set to 550kHz (LM2734Y) or 1.6MHz (LM2734X), allowing the use of extremely small surface mount inductors and chip capacitors. Even though the operating frequencies are very high, efficiencies up to 90% are easy to achieve. External shutdown is included, featuring an ultra-low stand-by current of 30nA. The LM2734 utilizes current-mode control and internal compensation to provide highperformance regulation over a wide range of operating conditions. Additional features include internal soft-start circuitry to reduce inrush current, pulse-by-pulse current limit, thermal shutdown, and output over-voltage protection. 1 2 3 4 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. WEBENCH is a registered trademark of Texas Instruments, Inc.. WEBENCH is a registered trademark of Texas Instruments. All other trademarks are the property of their respective owners. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright (c) 2004-2013, Texas Instruments Incorporated LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com Typical Application Circuit D2 VIN BOOST VIN C3 C1 L1 SW VOUT LM2734 ON D1 C2 EN R1 OFF FB GND R2 Figure 1. Figure 2. Efficiency vs Load Current VIN = 5V, VOUT = 3.3V Connection Diagram BOOST 1 6 SW 1 6 GND 2 5 VIN 2 5 FB 3 4 EN 3 4 Figure 3. 6-Lead SOT See Package Number DDC (R-PDSO-G6) Figure 4. Pin 1 Indentification PIN DESCRIPTIONS Pin Name 1 BOOST Boost voltage that drives the internal NMOS control switch. A bootstrap capacitor is connected between the BOOST and SW pins. Function 2 GND Signal and Power ground pin. Place the bottom resistor of the feedback network as close as possible to this pin for accurate regulation. 3 FB Feedback pin. Connect FB to the external resistor divider to set output voltage. 4 EN Enable control input. Logic high enables operation. Do not allow this pin to float or be greater than VIN + 0.3V. 5 VIN Input supply voltage. Connect a bypass capacitor to this pin. 6 SW Output switch. Connects to the inductor, catch diode, and bootstrap capacitor. These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. 2 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 Absolute Maximum Ratings (1) (2) VIN -0.5V to 24V SW Voltage -0.5V to 24V Boost Voltage -0.5V to 30V Boost to SW Voltage -0.5V to 6.0V FB Voltage -0.5V to 3.0V EN Voltage -0.5V to (VIN + 0.3V) Junction Temperature ESD Susceptibility 150C (3) 2kV Storage Temp. Range -65C to 150C Soldering Information Reflow Peak Pkg. Temp.(15sec) (1) (2) (3) 260C Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but specific performance is not ensured. For specific specifications and the test conditions, see Electrical Characteristics. If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and specifications. Human body model, 1.5k in series with 100pF. Operating Ratings (1) VIN 3V to 20V SW Voltage -0.5V to 20V Boost Voltage -0.5V to 25V Boost to SW Voltage 1.6V to 5.5V -40C to +125C Junction Temperature Range Thermal Resistance JA (2) (1) (2) 118C/W Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but specific performance is not ensured. For specific specifications and the test conditions, see Electrical Characteristics. Thermal shutdown will occur if the junction temperature exceeds 165C. The maximum power dissipation is a function of TJ(MAX) , JA and TA . The maximum allowable power dissipation at any ambient temperature is PD = (TJ(MAX) - TA)/JA . All numbers apply for packages soldered directly onto a 3" x 3" PC board with 2oz. copper on 4 layers in still air. For a 2 layer board using 1 oz. copper in still air, JA = 204C/W. Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 3 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com Electrical Characteristics Specifications with standard typeface are for TJ = 25C, and those in boldface type apply over the full Operating Temperature Range (TJ = -40C to 125C). VIN = 5V, VBOOST - VSW = 5V unless otherwise specified. Datasheet min/max specification limits are ensured by design, test, or statistical analysis. Symbol VFB VFB/VIN IFB UVLO Parameter Conditions Feedback Voltage Feedback Voltage Line Regulation VIN = 3V to 20V Feedback Input Bias Current Sink/Source Undervoltage Lockout VIN Rising Undervoltage Lockout VIN Falling UVLO Hysteresis FSW Switching Frequency DMAX Maximum Duty Cycle DMIN Minimum Duty Cycle RDS(ON) Max (1) 0.784 0.800 0.816 0.01 10 250 2.74 2.90 2.0 2.3 0.30 0.44 1.2 1.6 1.9 LM2734Y 0.40 0.55 0.66 LM2734X 85 92 LM2734Y 90 96 2 LM2734Y 1 % VBOOST - VSW = 3V IQ Quiescent Current Switching Quiescent Current (shutdown) VEN = 0V 30 LM2734X (50% Duty Cycle) 2.5 3.5 LM2734Y (50% Duty Cycle) 1.0 1.8 Shutdown Threshold Voltage VEN Falling Enable Threshold Voltage VEN Rising IEN Enable Pin Current Sink/Source ISW Switch Leakage MHz % VBOOST - VSW = 3V Boost Pin Current nA 0.62 Switch Current Limit 1.2 V V LM2734X LM2734X Units %/V Switch ON Resistance VEN_TH 4 Typ (2) ICL IBOOST (1) (2) Min (1) 300 600 1.7 2.5 A 1.5 2.5 mA nA 0.4 1.8 m mA V 10 nA 40 nA Specified to Average Outgoing Quality Level (AOQL). Typicals represent the most likely parametric norm. Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 Typical Performance Characteristics All curves taken at VIN = 5V, VBOOST - VSW = 5V, L1 = 4.7 H ("X"), L1 = 10 H ("Y"), and TA = 25C, unless specified otherwise. Efficiency vs Load Current - "X" VOUT = 5V Efficiency vs Load Current - "Y" VOUT = 5V Figure 5. Figure 6. Efficiency vs Load Current - "X" VOUT = 3.3V Efficiency vs Load Current - "Y" VOUT = 3.3V Figure 7. Figure 8. Efficiency vs Load Current - "X" VOUT = 1.5V Efficiency vs Load Current - "Y" VOUT = 1.5V Figure 9. Figure 10. Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 5 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com Typical Performance Characteristics (continued) All curves taken at VIN = 5V, VBOOST - VSW = 5V, L1 = 4.7 H ("X"), L1 = 10 H ("Y"), and TA = 25C, unless specified otherwise. 6 Oscillator Frequency vs Temperature - "X" Oscillator Frequency vs Temperature - "Y" Figure 11. Figure 12. Current Limit vs Temperature VIN = 5V Current Limit vs Temperature VIN = 20V Figure 13. Figure 14. VFB vs Temperature RDSON vs Temperature Figure 15. Figure 16. Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 Typical Performance Characteristics (continued) All curves taken at VIN = 5V, VBOOST - VSW = 5V, L1 = 4.7 H ("X"), L1 = 10 H ("Y"), and TA = 25C, unless specified otherwise. IQ Switching vs Temperature Line Regulation - "X" VOUT = 1.5V, IOUT = 500mA Figure 17. Figure 18. Line Regulation - "Y" VOUT = 1.5V, IOUT = 500mA Line Regulation - "X" VOUT = 3.3V, IOUT = 500mA Figure 19. Figure 20. Line Regulation - "Y" VOUT = 3.3V, IOUT = 500mA Figure 21. Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 7 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com Block Diagram VIN VIN Current-Sense Amplifier OFF EN Internal Regulator and Enable Circuit CIN D2 Thermal Shutdown BOOST VBOOST Under Voltage Lockout Oscillator RSENSE + - Current Limit Output Control Logic Reset Pulse + ISENSE + + Corrective Ramp 0.3: Switch Driver SW OVP Comparator - ON Error Signal D 1 + PWM Comparator CBOOST VSW L IL VOUT COUT 0.88V + - R 1 FB Internal Compensation + Error Amplifier + - VREF 0.8V R 2 GND Figure 22. 8 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 APPLICATION INFORMATION THEORY OF OPERATION The LM2734 is a constant frequency PWM buck regulator IC that delivers a 1A load current. The regulator has a preset switching frequency of either 550kHz (LM2734Y) or 1.6MHz (LM2734X). These high frequencies allow the LM2734 to operate with small surface mount capacitors and inductors, resulting in DC/DC converters that require a minimum amount of board space. The LM2734 is internally compensated, so it is simple to use, and requires few external components. The LM2734 uses current-mode control to regulate the output voltage. The following operating description of the LM2734 will refer to the Simplified Block Diagram (Figure 22) and to the waveforms in Figure 23. The LM2734 supplies a regulated output voltage by switching the internal NMOS control switch at constant frequency and variable duty cycle. A switching cycle begins at the falling edge of the reset pulse generated by the internal oscillator. When this pulse goes low, the output control logic turns on the internal NMOS control switch. During this on-time, the SW pin voltage (VSW) swings up to approximately VIN, and the inductor current (IL) increases with a linear slope. IL is measured by the current-sense amplifier, which generates an output proportional to the switch current. The sense signal is summed with the regulator's corrective ramp and compared to the error amplifier's output, which is proportional to the difference between the feedback voltage and VREF. When the PWM comparator output goes high, the output switch turns off until the next switching cycle begins. During the switch off-time, inductor current discharges through Schottky diode D1, which forces the SW pin to swing below ground by the forward voltage (VD) of the catch diode. The regulator loop adjusts the duty cycle (D) to maintain a constant output voltage. VSW D = TON/TSW VIN SW Voltage TOFF TON 0 VD t IL TSW IPK Inductor Current t 0 Figure 23. LM2734 Waveforms of SW Pin Voltage and Inductor Current BOOST FUNCTION Capacitor CBOOST and diode D2 in Figure 24 are used to generate a voltage VBOOST. VBOOST - VSW is the gate drive voltage to the internal NMOS control switch. To properly drive the internal NMOS switch during its on-time, VBOOST needs to be at least 1.6V greater than VSW. Although the LM2734 will operate with this minimum voltage, it may not have sufficient gate drive to supply large values of output current. Therefore, it is recommended that VBOOST be greater than 2.5V above VSW for best efficiency. VBOOST - VSW should not exceed the maximum operating limit of 5.5V. 5.5V > VBOOST - VSW > 2.5V for best performance. Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 9 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com VBOOST D2 BOOST VIN VIN LM2734 CIN CBOOST L SW VOUT GND COUT D1 Figure 24. VOUT Charges CBOOST When the LM2734 starts up, internal circuitry from the BOOST pin supplies a maximum of 20mA to CBOOST. This current charges CBOOST to a voltage sufficient to turn the switch on. The BOOST pin will continue to source current to CBOOST until the voltage at the feedback pin is greater than 0.76V. There are various methods to derive VBOOST: 1. From the input voltage (VIN) 2. From the output voltage (VOUT) 3. From an external distributed voltage rail (VEXT) 4. From a shunt or series zener diode In the Simplifed Block Diagram of Figure 22, capacitor CBOOST and diode D2 supply the gate-drive current for the NMOS switch. Capacitor CBOOST is charged via diode D2 by VIN. During a normal switching cycle, when the internal NMOS control switch is off (TOFF) (refer to Figure 23), VBOOST equals VIN minus the forward voltage of D2 (VFD2), during which the current in the inductor (L) forward biases the Schottky diode D1 (VFD1). Therefore the voltage stored across CBOOST is VBOOST - VSW = VIN - VFD2 + VFD1 (1) When the NMOS switch turns on (TON), the switch pin rises to VSW = VIN - (RDSON x IL), (2) forcing VBOOST to rise thus reverse biasing D2. The voltage at VBOOST is then VBOOST = 2VIN - (RDSON x IL) - VFD2 + VFD1 (3) which is approximately 2VIN - 0.4V (4) for many applications. Thus the gate-drive voltage of the NMOS switch is approximately VIN - 0.2V (5) An alternate method for charging CBOOST is to connect D2 to the output as shown in Figure 24. The output voltage should be between 2.5V and 5.5V, so that proper gate voltage will be applied to the internal switch. In this circuit, CBOOST provides a gate drive voltage that is slightly less than VOUT. In applications where both VIN and VOUT are greater than 5.5V, or less than 3V, CBOOST cannot be charged directly from these voltages. If VIN and VOUT are greater than 5.5V, CBOOST can be charged from VIN or VOUT minus a zener voltage by placing a zener diode D3 in series with D2, as shown in Figure 25. When using a series zener diode from the input, ensure that the regulation of the input supply doesn't create a voltage that falls outside the recommended VBOOST voltage. (VINMAX - VD3) < 5.5V (VINMIN - VD3) > 1.6V 10 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 D2 D3 VIN BOOST VIN CIN VBOOST CBOOST LM2734 L VOUT SW GND C OUT D1 Figure 25. Zener Reduces Boost Voltage from VIN An alternative method is to place the zener diode D3 in a shunt configuration as shown in Figure 26. A small 350mW to 500mW 5.1V zener in a SOT or SOD package can be used for this purpose. A small ceramic capacitor such as a 6.3V, 0.1F capacitor (C4) should be placed in parallel with the zener diode. When the internal NMOS switch turns on, a pulse of current is drawn to charge the internal NMOS gate capacitance. The 0.1 F parallel shunt capacitor ensures that the VBOOST voltage is maintained during this time. Resistor R3 should be chosen to provide enough RMS current to the zener diode (D3) and to the BOOST pin. A recommended choice for the zener current (IZENER) is 1 mA. The current IBOOST into the BOOST pin supplies the gate current of the NMOS control switch and varies typically according to the following formula for the X version: IBOOST = 0.56 x (D + 0.54) x (VZENER - VD2) mA (6) IBOOST can be calculated for the Y version using the following: IBOOST = 0.22 x (D + 0.54) x (VZENER - VD2) A (7) where D is the duty cycle, VZENER and VD2 are in volts, and IBOOST is in milliamps. VZENER is the voltage applied to the anode of the boost diode (D2), and VD2 is the average forward voltage across D2. Note that this formula for IBOOST gives typical current. For the worst case IBOOST, increase the current by 40%. In that case, the worst case boost current will be IBOOST-MAX = 1.4 x IBOOST (8) R3 will then be given by R3 = (VIN - VZENER) / (1.4 x IBOOST + IZENER) (9) For example, using the X-version let VIN = 10V, VZENER = 5V, VD2 = 0.7V, IZENER = 1mA, and duty cycle D = 50%. Then IBOOST = 0.56 x (0.5 + 0.54) x (5 - 0.7) mA = 2.5mA R3 = (10V - 5V) / (1.4 x 2.5mA + 1mA) = 1.11k (10) (11) VZ C4 D2 D3 R3 VIN VIN C IN BOOST VBOOST CBOOST LM2734 L SW VOUT GND D1 COUT Figure 26. Boost Voltage Supplied from the Shunt Zener on VIN Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 11 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com ENABLE PIN / SHUTDOWN MODE The LM2734 has a shutdown mode that is controlled by the enable pin (EN). When a logic low voltage is applied to EN, the part is in shutdown mode and its quiescent current drops to typically 30nA. Switch leakage adds another 40nA from the input supply. The voltage at this pin should never exceed VIN + 0.3V. SOFT-START This function forces VOUT to increase at a controlled rate during start up. During soft-start, the error amplifier's reference voltage ramps from 0V to its nominal value of 0.8V in approximately 200s. This forces the regulator output to ramp up in a more linear and controlled fashion, which helps reduce inrush current. Under some circumstances at start-up, an output voltage overshoot may still be observed. This may be due to a large output load applied during start up. Large amounts of output external capacitance can also increase output voltage overshoot. A simple solution is to add a feed forward capacitor with a value between 470pf and 1000pf across the top feedback resistor (R1). See Figure 28 for further detail. OUTPUT OVERVOLTAGE PROTECTION The overvoltage comparator compares the FB pin voltage to a voltage that is 10% higher than the internal reference Vref. Once the FB pin voltage goes 10% above the internal reference, the internal NMOS control switch is turned off, which allows the output voltage to decrease toward regulation. UNDERVOLTAGE LOCKOUT Undervoltage lockout (UVLO) prevents the LM2734 from operating until the input voltage exceeds 2.74V(typ). The UVLO threshold has approximately 440mV of hysteresis, so the part will operate until VIN drops below 2.3V(typ). Hysteresis prevents the part from turning off during power up if VIN is non-monotonic. CURRENT LIMIT The LM2734 uses cycle-by-cycle current limiting to protect the output switch. During each switching cycle, a current limit comparator detects if the output switch current exceeds 1.7A (typ), and turns off the switch until the next switching cycle begins. THERMAL SHUTDOWN Thermal shutdown limits total power dissipation by turning off the output switch when the IC junction temperature exceeds 165C. After thermal shutdown occurs, the output switch doesn't turn on until the junction temperature drops to approximately 150C. Design Guide INDUCTOR SELECTION The Duty Cycle (D) can be approximated quickly using the ratio of output voltage (VO) to input voltage (VIN): VO D= VIN (12) The catch diode (D1) forward voltage drop and the voltage drop across the internal NMOS must be included to calculate a more accurate duty cycle. Calculate D by using the following formula: VO + VD D= VIN + VD - VSW (13) VSW can be approximated by: VSW = IO x RDS(ON) (14) The diode forward drop (VD) can range from 0.3V to 0.7V depending on the quality of the diode. The lower VD is, the higher the operating efficiency of the converter. 12 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 The inductor value determines the output ripple current. Lower inductor values decrease the size of the inductor, but increase the output ripple current. An increase in the inductor value will decrease the output ripple current. The ratio of ripple current (iL) to output current (IO) is optimized when it is set between 0.3 and 0.4 at 1A. The ratio r is defined as: r= 'iL lO (15) One must also ensure that the minimum current limit (1.2A) is not exceeded, so the peak current in the inductor must be calculated. The peak current (ILPK) in the inductor is calculated by: ILPK = IO + IL/2 (16) If r = 0.5 at an output of 1A, the peak current in the inductor will be 1.25A. The minimum specified current limit over all operating conditions is 1.2A. One can either reduce r to 0.4 resulting in a 1.2A peak current, or make the engineering judgement that 50mA over will be safe enough with a 1.7A typical current limit and 6 sigma limits. When the designed maximum output current is reduced, the ratio r can be increased. At a current of 0.1A, r can be made as high as 0.9. The ripple ratio can be increased at lighter loads because the net ripple is actually quite low, and if r remains constant the inductor value can be made quite large. An equation empirically developed for the maximum ripple ratio at any current below 2A is: r = 0.387 x IOUT-0.3667 (17) Note that this is just a guideline. The LM2734 operates at frequencies allowing the use of ceramic output capacitors without compromising transient response. Ceramic capacitors allow higher inductor ripple without significantly increasing output ripple. See the output capacitor section for more details on calculating output voltage ripple. Now that the ripple current or ripple ratio is determined, the inductance is calculated by: L= VO + VD IO x r x fS x (1-D) (18) where fs is the switching frequency and IO is the output current. When selecting an inductor, make sure that it is capable of supporting the peak output current without saturating. Inductor saturation will result in a sudden reduction in inductance and prevent the regulator from operating correctly. Because of the speed of the internal current limit, the peak current of the inductor need only be specified for the required maximum output current. For example, if the designed maximum output current is 0.5A and the peak current is 0.7A, then the inductor should be specified with a saturation current limit of >0.7A. There is no need to specify the saturation or peak current of the inductor at the 1.7A typical switch current limit. The difference in inductor size is a factor of 5. Because of the operating frequency of the LM2734, ferrite based inductors are preferred to minimize core losses. This presents little restriction since the variety of ferrite based inductors is huge. Lastly, inductors with lower series resistance (DCR) will provide better operating efficiency. For recommended inductors see Example Circuits. INPUT CAPACITOR An input capacitor is necessary to ensure that VIN does not drop excessively during switching transients. The primary specifications of the input capacitor are capacitance, voltage, RMS current rating, and ESL (Equivalent Series Inductance). The recommended input capacitance is 10F, although 4.7F works well for input voltages below 6V. The input voltage rating is specifically stated by the capacitor manufacturer. Make sure to check any recommended deratings and also verify if there is any significant change in capacitance at the operating input voltage and the operating temperature. The input capacitor maximum RMS input current rating (IRMS-IN) must be greater than: IRMS-IN = IO x r2 D x 1-D + 12 (19) It can be shown from the above equation that maximum RMS capacitor current occurs when D = 0.5. Always calculate the RMS at the point where the duty cycle, D, is closest to 0.5. The ESL of an input capacitor is usually determined by the effective cross sectional area of the current path. A large leaded capacitor will have high ESL and a 0805 ceramic chip capacitor will have very low ESL. At the operating frequencies of the LM2734, certain capacitors may have an ESL so large that the resulting impedance (2fL) will be higher than that required to Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 13 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com provide stable operation. As a result, surface mount capacitors are strongly recommended. Sanyo POSCAP, Tantalum or Niobium, Panasonic SP or Cornell Dubilier ESR, and multilayer ceramic capacitors (MLCC) are all good choices for both input and output capacitors and have very low ESL. For MLCCs it is recommended to use X7R or X5R dielectrics. Consult capacitor manufacturer datasheet to see how rated capacitance varies over operating conditions. OUTPUT CAPACITOR The output capacitor is selected based upon the desired output ripple and transient response. The initial current of a load transient is provided mainly by the output capacitor. The output ripple of the converter is: 'VO = 'iL x (RESR + 1 ) 8 x fS x CO (20) When using MLCCs, the ESR is typically so low that the capacitive ripple may dominate. When this occurs, the output ripple will be approximately sinusoidal and 90 phase shifted from the switching action. Given the availability and quality of MLCCs and the expected output voltage of designs using the LM2734, there is really no need to review any other capacitor technologies. Another benefit of ceramic capacitors is their ability to bypass high frequency noise. A certain amount of switching edge noise will couple through parasitic capacitances in the inductor to the output. A ceramic capacitor will bypass this noise while a tantalum will not. Since the output capacitor is one of the two external components that control the stability of the regulator control loop, most applications will require a minimum at 10 F of output capacitance. Capacitance can be increased significantly with little detriment to the regulator stability. Like the input capacitor, recommended multilayer ceramic capacitors are X7R or X5R. Again, verify actual capacitance at the desired operating voltage and temperature. Check the RMS current rating of the capacitor. The RMS current rating of the capacitor chosen must also meet the following condition: r 12 IRMS-OUT = IO x (21) CATCH DIODE The catch diode (D1) conducts during the switch off-time. A Schottky diode is recommended for its fast switching times and low forward voltage drop. The catch diode should be chosen so that its current rating is greater than: ID1 = IO x (1-D) (22) The reverse breakdown rating of the diode must be at least the maximum input voltage plus appropriate margin. To improve efficiency choose a Schottky diode with a low forward voltage drop. BOOST DIODE A standard diode such as the 1N4148 type is recommended. For VBOOST circuits derived from voltages less than 3.3V, a small-signal Schottky diode is recommended for greater efficiency. A good choice is the BAT54 small signal diode. BOOST CAPACITOR A ceramic 0.01F capacitor with a voltage rating of at least 6.3V is sufficient. The X7R and X5R MLCCs provide the best performance. OUTPUT VOLTAGE The output voltage is set using the following equation where R2 is connected between the FB pin and GND, and R1 is connected between VO and the FB pin. A good value for R2 is 10k. R1 = 14 VO VREF - 1 x R2 (23) Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 PCB Layout Considerations When planning layout there are a few things to consider when trying to achieve a clean, regulated output. The most important consideration when completing the layout is the close coupling of the GND connections of the CIN capacitor and the catch diode D1. These ground ends should be close to one another and be connected to the GND plane with at least two through-holes. Place these components as close to the IC as possible. Next in importance is the location of the GND connection of the COUT capacitor, which should be near the GND connections of CIN and D1. There should be a continuous ground plane on the bottom layer of a two-layer board except under the switching node island. The FB pin is a high impedance node and care should be taken to make the FB trace short to avoid noise pickup and inaccurate regulation. The feedback resistors should be placed as close as possible to the IC, with the GND of R2 placed as close as possible to the GND of the IC. The VOUT trace to R1 should be routed away from the inductor and any other traces that are switching. High AC currents flow through the VIN, SW and VOUT traces, so they should be as short and wide as possible. However, making the traces wide increases radiated noise, so the designer must make this trade-off. Radiated noise can be decreased by choosing a shielded inductor. The remaining components should also be placed as close as possible to the IC. Please see Application Note AN-1229 SNVA054 for further considerations and the LM2734 demo board as an example of a four-layer layout. LM2734X Circuit Examples D2 VIN BOOST VIN C3 C1 L1 R3 VOUT SW LM2734 ON D1 EN C2 R1 OFF FB GND R2 Figure 27. LM2734X (1.6MHz) VBOOST Derived from VIN 5V to 1.5V/1A Table 1. Bill of Materials for Figure 27 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734X Texas Instruments C1, Input Cap 10F, 6.3V, X5R C3216X5ROJ106M TDK C2, Output Cap 10F, 6.3V, X5R C3216X5ROJ106M TDK C3, Boost Cap 0.01uF, 16V, X7R C1005X7R1C103K TDK D1, Catch Diode 0.3VF Schottky 1A, 10VR MBRM110L ON Semi D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. L1 4.7H, 1.7A, VLCF4020T- 4R7N1R2 TDK R1 8.87k, 1% CRCW06038871F Vishay R2 10.2k, 1% CRCW06031022F Vishay R3 100k, 1% CRCW06031003F Vishay Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 15 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com D2 VIN 12V BOOST VIN C3 C1 R3 L1 VOUT 3.3V SW LM2734 D1 C2 ON EN R1 CFF OFF FB GND R2 Figure 28. LM2734X (1.6MHz) VBOOST Derived from VOUT 12V to 3.3V/1A Table 2. Bill of Materials for Figure 28 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator NSC LM2734X C1, Input Cap 10F, 25V, X7R C3225X7R1E106M TDK C2, Output Cap 22F, 6.3V, X5R C3216X5ROJ226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK CFF 1000pF 25V C0603X5R1E102K TDK D1, Catch Diode 0.34VF Schottky 1A, 30VR SS1P3L Vishay D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. L1 4.7H, 1.7A VLCF4020T- 4R7N1R2 TDK R1 31.6k, 1% CRCW06033162F Vishay R2 10k, 1% CRCW06031002F Vishay R3 100k, 1% CRCW06031003F Vishay 16 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 C4 D3 R4 D2 BOOST VIN VIN C3 C1 R3 L1 VOUT SW LM2734 ON D1 C2 EN OFF R1 FB GND R2 Figure 29. LM2734X (1.6MHz) VBOOST Derived from VSHUNT 18V to 1.5V/1A Table 3. Bill of Materials for Figure 29 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734X Texas Instruments C1, Input Cap 10F, 25V, X7R C3225X7R1E106M TDK C2, Output Cap 22F, 6.3V, X5R C3216X5ROJ226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK C4, Shunt Cap 0.1F, 6.3V, X5R C1005X5R0J104K TDK D1, Catch Diode 0.4VF Schottky 1A, 30VR SS1P3L Vishay D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. D3, Zener Diode 5.1V 250Mw SOT BZX84C5V1 Vishay L1 6.8H, 1.6A, SLF7032T-6R8M1R6 TDK R1 8.87k, 1% CRCW06038871F Vishay R2 10.2k, 1% CRCW06031022F Vishay R3 100k, 1% CRCW06031003F Vishay R4 4.12k, 1% CRCW06034121F Vishay Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 17 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com D3 D2 BOOST VIN VIN C1 C3 R3 L1 VOUT SW LM2734 ON D1 EN C2 R1 OFF FB GND R2 Figure 30. LM2734X (1.6MHz) VBOOST Derived from Series Zener Diode (VIN) 15V to 1.5V/1A Table 4. Bill of Materials for Figure 30 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734X Texas Instruments C1, Input Cap 10F, 25V, X7R C3225X7R1E106M TDK C2, Output Cap 22F, 6.3V, X5R C3216X5ROJ226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK D1, Catch Diode 0.4VF Schottky 1A, 30VR SS1P3L Vishay D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. D3, Zener Diode 11V 350Mw SOT BZX84C11T Diodes, Inc. L1 6.8H, 1.6A, SLF7032T-6R8M1R6 TDK R1 8.87k, 1% CRCW06038871F Vishay R2 10.2k, 1% CRCW06031022F Vishay R3 100k, 1% CRCW06031003F Vishay 18 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 D3 D2 VIN BOOST VIN C3 C1 R3 L1 VOUT SW LM2734 ON D1 EN C2 R1 OFF FB GND R2 Figure 31. LM2734X (1.6MHz) VBOOST Derived from Series Zener Diode (VOUT) 15V to 9V/1A Table 5. Bill of Materials for Figure 31 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734X Texas Instruments C1, Input Cap 10F, 25V, X7R C3225X7R1E106M TDK C2, Output Cap 22F, 16V, X5R C3216X5R1C226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK D1, Catch Diode 0.4VF Schottky 1A, 30VR SS1P3L Vishay D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. D3, Zener Diode 4.3V 350mw SOT BZX84C4V3 Diodes, Inc. L1 6.8H, 1.6A, SLF7032T-6R8M1R6 TDK R1 102k, 1% CRCW06031023F Vishay R2 10.2k, 1% CRCW06031022F Vishay R3 100k, 1% CRCW06031003F Vishay Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 19 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com LM2734Y Circuit Examples D2 VIN BOOST VIN C3 C1 L1 R3 VOUT SW LM2734 ON D1 EN C2 R1 OFF FB GND R2 Figure 32. LM2734Y (550kHz) VBOOST Derived from VIN 5V to 1.5V/1A Table 6. Bill of Materials for Figure 32 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734Y Texas Instruments C1, Input Cap 10F, 6.3V, X5R C3216X5ROJ106M TDK C2, Output Cap 22F, 6.3V, X5R C3216X5ROJ226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK D1, Catch Diode 0.3VF Schottky 1A, 10VR MBRM110L ON Semi D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. L1 10H, 1.6A, SLF7032T-100M1R4 TDK R1 8.87k, 1% CRCW06038871F Vishay R2 10.2k, 1% CRCW06031022F Vishay R3 100k, 1% CRCW06031003F Vishay 20 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 D2 VIN 12V BOOST VIN C3 C1 R3 L1 VOUT 3.3V SW LM2734 D1 C2 ON EN R1 CFF OFF FB GND R2 Figure 33. LM2734Y (550kHz) VBOOST Derived from VOUT 12V to 3.3V/1A Table 7. Bill of Materials for Figure 33 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734Y Texas Instruments C1, Input Cap 10F, 25V, X7R C3225X7R1E106M TDK C2, Output Cap 22F, 6.3V, X5R C3216X5ROJ226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK D1, Catch Diode 0.34VF Schottky 1A, 30VR SS1P3L Vishay D2, Boost Diode 0.6VF @ 30mA Diode BAT17 Vishay L1 10H, 1.6A, SLF7032T-100M1R4 TDK R1 31.6k, 1% CRCW06033162F Vishay R2 10.0 k, 1% CRCW06031002F Vishay R3 100k, 1% CRCW06031003F Vishay Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 21 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com C4 D3 R4 D2 BOOST VIN VIN C3 C1 R3 L1 VOUT SW LM2734 ON D1 C2 EN OFF R1 FB GND R2 Figure 34. LM2734Y (550kHz) VBOOST Derived from VSHUNT 18V to 1.5V/1A Table 8. Bill of Materials for Figure 34 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734Y Texas Instruments C1, Input Cap 10F, 25V, X7R C3225X7R1E106M TDK C2, Output Cap 22F, 6.3V, X5R C3216X5ROJ226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK C4, Shunt Cap 0.1F, 6.3V, X5R C1005X5R0J104K TDK D1, Catch Diode 0.4VF Schottky 1A, 30VR SS1P3L Vishay D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. D3, Zener Diode 5.1V 250Mw SOT BZX84C5V1 Vishay L1 15H, 1.5A SLF7045T-150M1R5 TDK R1 8.87k, 1% CRCW06038871F Vishay R2 10.2k, 1% CRCW06031022F Vishay R3 100k, 1% CRCW06031003F Vishay R4 4.12k, 1% CRCW06034121F Vishay 22 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 D3 D2 BOOST VIN VIN C1 C3 R3 L1 VOUT SW LM2734 ON D1 EN C2 R1 OFF FB GND R2 Figure 35. LM2734Y (550kHz) VBOOST Derived from Series Zener Diode (VIN) 15V to 1.5V/1A Table 9. Bill of Materials for Figure 35 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734Y Texas Instruments C1, Input Cap 10F, 25V, X7R C3225X7R1E106M TDK C2, Output Cap 22F, 6.3V, X5R C3216X5ROJ226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK D1, Catch Diode 0.4VF Schottky 1A, 30VR SS1P3L Vishay D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. D3, Zener Diode 11V 350Mw SOT BZX84C11T Diodes, Inc. L1 15H, 1.5A, SLF7045T-150M1R5 TDK R1 8.87k, 1% CRCW06038871F Vishay R2 10.2k, 1% CRCW06031022F Vishay R3 100k, 1% CRCW06031003F Vishay Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 23 LM2734 SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 www.ti.com D3 D2 VIN BOOST VIN C3 C1 R3 L1 VOUT SW LM2734 ON D1 EN C2 R1 OFF FB GND R2 Figure 36. LM2734Y (550kHz) VBOOST Derived from Series Zener Diode (VOUT) 15V to 9V/1A Table 10. Bill of Materials for Figure 36 Part ID Part Value Part Number Manufacturer U1 1A Buck Regulator LM2734Y Texas Instruments C1, Input Cap 10F, 25V, X7R C3225X7R1E106M TDK C2, Output Cap 22F, 16V, X5R C3216X5R1C226M TDK C3, Boost Cap 0.01F, 16V, X7R C1005X7R1C103K TDK D1, Catch Diode 0.4VF Schottky 1A, 30VR SS1P3L Vishay D2, Boost Diode 1VF @ 50mA Diode 1N4148W Diodes, Inc. D3, Zener Diode 4.3V 350mw SOT BZX84C4V3 Diodes, Inc. L1 22H, 1.4A, SLF7045T-220M1R3-1PF TDK R1 102k, 1% CRCW06031023F Vishay R2 10.2k, 1% CRCW06031022F Vishay R3 100k, 1% CRCW06031003F Vishay 24 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 LM2734 www.ti.com SNVS288I - SEPTEMBER 2004 - REVISED APRIIL 2013 REVISION HISTORY Changes from Revision H (April 2013) to Revision I * Page Changed layout of National Data Sheet to TI format .......................................................................................................... 24 Submit Documentation Feedback Copyright (c) 2004-2013, Texas Instruments Incorporated Product Folder Links: LM2734 25 PACKAGE OPTION ADDENDUM www.ti.com 1-Nov-2013 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (C) Device Marking (4/5) LM2734XMK/NOPB ACTIVE SOT DDC 6 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SFDB LM2734XMKX/NOPB ACTIVE SOT DDC 6 3000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SFDB LM2734XQMK/NOPB ACTIVE SOT DDC 6 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SUKB LM2734XQMKE/NOPB ACTIVE SOT DDC 6 250 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SUKB LM2734XQMKX/NOPB ACTIVE SOT DDC 6 3000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SUKB LM2734YMK NRND SOT DDC 6 1000 TBD Call TI Call TI -40 to 125 SFEB LM2734YMK/NOPB ACTIVE SOT DDC 6 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SFEB LM2734YMKX NRND SOT DDC 6 3000 TBD Call TI Call TI -40 to 125 SFEB LM2734YMKX/NOPB ACTIVE SOT DDC 6 3000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SFEB LM2734YQMK/NOPB ACTIVE SOT DDC 6 1000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SVCB LM2734YQMKE/NOPB ACTIVE SOT DDC 6 250 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SVCB LM2734YQMKX/NOPB ACTIVE SOT DDC 6 3000 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 SVCB (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Addendum-Page 1 Samples PACKAGE OPTION ADDENDUM www.ti.com 1-Nov-2013 Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish value exceeds the maximum column width. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. OTHER QUALIFIED VERSIONS OF LM2734, LM2734-Q1 : * Catalog: LM2734 * Automotive: LM2734-Q1 NOTE: Qualified Version Definitions: * Catalog - TI's standard catalog product * Automotive - Q100 devices qualified for high-reliability automotive applications targeting zero defects Addendum-Page 2 PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant LM2734XMK/NOPB SOT DDC 6 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734XMKX/NOPB SOT DDC 6 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734XQMK/NOPB SOT DDC 6 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734XQMKE/NOPB SOT DDC 6 250 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734XQMKX/NOPB SOT DDC 6 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734YMK SOT DDC 6 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734YMK/NOPB SOT DDC 6 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734YMKX SOT DDC 6 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734YMKX/NOPB SOT DDC 6 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734YQMK/NOPB SOT DDC 6 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734YQMKE/NOPB SOT DDC 6 250 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 LM2734YQMKX/NOPB SOT DDC 6 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3 Pack Materials-Page 1 PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM2734XMK/NOPB SOT DDC 6 1000 210.0 185.0 35.0 LM2734XMKX/NOPB SOT DDC 6 3000 210.0 185.0 35.0 LM2734XQMK/NOPB SOT DDC 6 1000 210.0 185.0 35.0 LM2734XQMKE/NOPB SOT DDC 6 250 210.0 185.0 35.0 LM2734XQMKX/NOPB SOT DDC 6 3000 210.0 185.0 35.0 LM2734YMK SOT DDC 6 1000 210.0 185.0 35.0 LM2734YMK/NOPB SOT DDC 6 1000 210.0 185.0 35.0 LM2734YMKX SOT DDC 6 3000 210.0 185.0 35.0 LM2734YMKX/NOPB SOT DDC 6 3000 210.0 185.0 35.0 LM2734YQMK/NOPB SOT DDC 6 1000 210.0 185.0 35.0 LM2734YQMKE/NOPB SOT DDC 6 250 210.0 185.0 35.0 LM2734YQMKX/NOPB SOT DDC 6 3000 210.0 185.0 35.0 Pack Materials-Page 2 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All semiconductor products (also referred to herein as "components") are sold subject to TI's terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI's terms and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily performed. TI assumes no liability for applications assistance or the design of Buyers' products. Buyers are responsible for their products and applications using TI components. To minimize the risks associated with Buyers' products and applications, Buyers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional restrictions. Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use of any TI components in safety-critical applications. In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI's goal is to help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and requirements. Nonetheless, such components are subject to these terms. No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties have executed a special agreement specifically governing such use. Only those TI components which TI has specifically designated as military grade or "enhanced plastic" are designed and intended for use in military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and regulatory requirements in connection with such use. TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of non-designated products, TI will not be responsible for any failure to meet ISO/TS16949. Products Applications Audio www.ti.com/audio Automotive and Transportation www.ti.com/automotive Amplifiers amplifier.ti.com Communications and Telecom www.ti.com/communications Data Converters dataconverter.ti.com Computers and Peripherals www.ti.com/computers DLP(R) Products www.dlp.com Consumer Electronics www.ti.com/consumer-apps DSP dsp.ti.com Energy and Lighting www.ti.com/energy Clocks and Timers www.ti.com/clocks Industrial www.ti.com/industrial Interface interface.ti.com Medical www.ti.com/medical Logic logic.ti.com Security www.ti.com/security Power Mgmt power.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video RFID www.ti-rfid.com OMAP Applications Processors www.ti.com/omap TI E2E Community e2e.ti.com Wireless Connectivity www.ti.com/wirelessconnectivity Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265 Copyright (c) 2013, Texas Instruments Incorporated