JULY 2000 ML4831* Electronic Ballast Controller GENERAL DESCRIPTION FEATURES The ML4831 is a complete solution for a dimmable, high power factor, high efficiency electronic ballast. Contained in the ML4831 are controllers for "boost" type power factor correction as well as for a dimming ballast. The Power factor circuit uses the average current sensing method with a gain modulator and over-voltage protection. This system produces power factors of better than 0.99 with low input current THD at > 95% efficiency. Special care has been taken in the design of the ML4831 to increase system noise immunity by using a high amplitude oscillator, and a current fed multiplier. An over-voltage protection comparator inhibits the PFC section in the event of a lamp out or lamp failure condition. The ballast section provides for programmable starting scenarios with programmable preheat and lamp out-ofsocket interrupt times. The IC controls lamp output through either frequency modulation using lamp current feedback. The ML4831 is designed using Micro Linear`s SemiStandard tile array technology. Customized versions of this IC, optimized to specific ballast architectures can be made available. Contact Micro Linear or an authorized representative for more information. Complete Power Factor Correction and Dimming Ballast Control on one IC Low Distortion, High Efficiency Continuous Boost, Average Current sensing PFC section Programmable Start Scenario for Rapid or Instant Start Lamps Lamp Current feedback for Dimming Control Variable Frequency dimming and starting Programmable Restart for lamp out condition to reduce ballast heating Over-Temperature Shutdown replaces external heat sensor for safety PFC Over-Voltage comparator eliminates output "runaway" due to load removal Large oscillator amplitude and gain modulator improves noise immunity * This product is End Of Life as of July 1, 2000 BLOCK DIAGRAM 7 8 INTERRUPT R(SET) R(T)/C(T) LAMP F.B. OSCILLATOR LFB OUT 9 5 6 OUTPUT DRIVERS 10 R(X)/C(X) PRE-HEAT AND INTERRUPT TIMERS OUT A CONTROL & GATING LOGIC OUT B PFC OUT 2 4 3 1 18 IA OUT 14 13 15 IA+ I(SINE) EA OUT EA-/OVP POWER FACTOR CONTROLLER PGND VCC UNDER-VOLTAGE AND THERMAL SHUTDOWN VREF GND 12 16 17 11 1 ML4831 PIN CONFIGURATION ML4831 18-Pin DIP (P18) EA OUT 1 18 EA-/OVP IA OUT 2 17 VREF I(SINE) 3 16 VCC IA+ 4 15 PFC OUT LAMP F.B. 5 14 OUT A LFB OUT 6 13 OUT B R(SET) 7 12 P GND R(T)/C(T) 8 11 GND INTERRUPT 9 10 R(X)/C(X) TOP VIEW PIN DESCRIPTION PIN# NAME 1 EA OUT PFC Error Amplifier output and compensation node 2 IA OUT Output and compensation node of the PFC average current transconductance amplifier. 3 I(SINE) PFC gain modulator input. 4 IA+ Non-inverting input of the PFC average current transconductance amplifier and peak current sense point of the PFC cycle by cycle current limit comparator. 5 2 FUNCTION LAMP F.B. PIN# NAME FUNCTION 8 R(T)C(T) Oscillator timing components 9 INTERRUPT Input used for lamp-out detection and restart. A voltage greater than 7.5 volts resets the chip and causes a restart after a programmable interval. 10 R(X)/C(X) Sets the timing for the preheat, dimming lockout, and interrupt 11 GND Ground 12 P GND Power ground for the IC 13 OUT B Ballast MOSFET drive output Inverting input of an Error Amplifier used to sense (and regulate) lamp arc current. Also the input node for dimming control. 14 OUT A Ballast MOSFET drive output 15 PFC OUT Power Factor MOSFET drive output 16 VCC Positive Supply for the IC 17 VREF Buffered output for the 7.5V voltage reference 18 EA-/OVP Inverting input to PFC error amplifier and OVP comparator input 6 LFB OUT Output from the Lamp Current Error Transconductance Amplifier used for lamp current loop compensation 7 R(SET) External resistor which sets oscillator FMAX, and R(X)/C(X) charging current ML4831 ABSOLUTE MAXIMUM RATINGS Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. Supply Current (ICC) ............................................... 75mA Output Current, Source or Sink (Pins 13, 14, 15) DC ................................................................... 250mA Output Energy (capacitive load per cycle) .............. 1.5 mJ Gain Modulator I(SINE) Input (Pin 3) ..................... 10 mA Analog Inputs (Pins 5, 9, 18) ............... -0.3V to VCC -2V Pin 4 input voltage ........................................... -3V to 2V Maximum Forced Voltage (Pins 1, 6) .......... -0.3V to 7.7V Maximum Forced Current (Pins 1, 2, 6) ................ 20mA Maximum Forced Voltage (Pin 2) .................. -0.3V to 6V Junction Temperature ............................................. 150C Storage Temperature Range ..................... -65C to 150C Lead Temperature (Soldering 10 Sec.) ..................... 260C Thermal Resistance (JA) Plastic DIP-P ................................................... 70C/W OPERATING CONDITIONS Temperature Range ML4831C .................................................. 0C to 85C ELECTRICAL CHARACTERISTICS Unless otherwise specified, R(SET) = 31.6k, R(T) = 16.2k, C(T) = 1.5nF, TJ = Junction Operating Temperature Range, ICC = 25mA PARAMETER CONDITIONS MIN TYP MAX UNITS Small Signal Transconductance 130 200 270 mhos Input Voltage Range -0.3 3.5 V 0.2 0.4 V 5.6 6 V PFC Current Sense Amplifier (Pins 2, 4) Output Low ISINE = 0mA, VPIN1 = 0V, VPIN4 = -0.3V, RL = Output High ISINE = 1.5mA, VPIN18/4 = 0V, RL = Source Current ISINE = 1.5mA, VPIN18/4 = 0V, VPIN2 = 5V -0.3 mA Sink Current ISINE = 0mA, VPIN2 = 0.3V, VPIN4 = -0.3V, VPIN1 = 0V 0.3 mA 5.2 PFC Voltage Feedback Amplifier (Pins 1, 18)/Lamp Current Amplifier (Pins 5, 6) Input Offset Voltage 3.0 10.0 mV Input Bias Current -0.3 -1.0 A 80 110 mhos 3.5 V 0.4 V Small Signal Transconductance 50 Input Voltage Range -0.3 Output Low VPIN5/18 = 3V, RL = Output High VPIN5/18 = 2V, RL = Source Current Sink Current 0.2 7.2 7.5 V VPIN5/18 = 0V, VPIN1/6 = 7V -0.2 mA VPIN5/18 = 5V, VPIN1/6 = 0.3V 0.2 mA ISINE = 100A, VPIN1 = 3V 40 mV ISINE = 300A, VPIN1 = 3V 130 mV ISINE =100A, VPIN1 = 6V 112 mV ISINE = 300A, VPIN1 = 6V 350 mV Output Voltage Limit ISINE = 1.5mA, VPIN18 = 0V 865 mV Offset Voltage ISINE = 0, VPIN18 = 0V 15 mV ISINE = 150A, VPIN18 = 3V 15 mV 1.8 V Gain Modulator Output Voltage I(SINE) Input Voltage ISINE = 200A 0.8 1.4 3 ML4831 ELECTRICAL CHARACTERISTICS (Continued) PARAMETER CONDITIONS MIN TYP MAX UNITS 72 76 80 kHz Oscillator Initial accuracy TA = 25C Voltage stability VCCZ - 3V < VCC <VCCZ - 0.5V Temperature stability Total Variation Line, temperature C(T) Discharge Current % 2 % 69 Ramp Valley to Peak C(T) Charging Current (FM Modes) 1 83 kHz 2.5 V VPIN5 = 3V, VPIN8 = 2.5V, VPIN10 = 0.9V (Preheat) -78 A VPIN5 = 3V, VPIN8 = 2.5V, VPIN10 = Open -156 A 5 mA 0.75 s VPIN8 = 2.5V Output Drive Deadtime Reference Section Output Voltage TA = 25C, IO = 1mA Line regulation Load regulation 7.4 7.5 7.6 V VCCZ - 3V < VCC < VCCZ - 0.5V 2 10 mV 1mA < IO < 20mA 2 15 mV Temperature stability 0.4 7.35 % Total Variation Line, load, temp 7.65 V Output Noise Voltage 10Hz to 10KHz 50 V Long Term Stability TJ = 125C, 1000 hrs 5 mV Short Circuit Current VCC < VCCZ - 0.5V, VREF = 0V -40 mA Initial Preheat Period 0.8 s Subsequent Preheat Period 0.7 s Start Period 2.1 s Interrupt Period 6.3 s Pin 10 Charging Current -19 A Preheat and Interrupt Timer (Pin 10) (R(X) = 590K, C(X) = 5.6F) Pin 10 Open Circuit Voltage VCC = 12.3V in UVLO Pin 10 Maximum Voltage 0.4 0.9 1.1 V 7.0 7.3 7.7 V -0.2 A Preheat Lower Threshold 1.18 V Preheat Upper Threshold 3.36 V Interrupt Recovery Threshold 1.18 V Start Period End Threshold 6.7 V Input Bias Current VPIN10 = 1.2V Interrupt Input (Pin 9) Interrupt Threshold Input Bias Current 4 7.35 7.5 7.65 V -0.3 -1 A ML4831 ELECTRICAL CHARACTERISTICS (Continued) PARAMETER CONDITIONS MIN TYP MAX UNITS 2.6 2.7 2.8 V OVP Comparator (Pin 18) OVP Threshold Hysteresis 0.25 V Propagation Delay 500 ns Outputs Output Voltage Low Output Voltage High IOUT = 20mA 0.4 0.8 V IOUT = 200mA 2.1 3.0 V IOUT = -20mA VCC - 2.5 VCC - 1.9 V IOUT = -200mA VCC - 3.0 VCC - 2.2 V Output Voltage Low in UVLO IOUT = 10mA, VCC = 8V 0.8 Output Rise/Fall Time CL = 1000pF 50 1.5 V ns Under-Voltage Lockout and Bias Circuits IC Shunt Voltage (VCCZ) ICC = 25mA VCCZ Load Regulation 25mA < ICC < 68mA VCCZ Total Variation Load, Temp Start-up Current VCC 12.3V Operating Current VCC = VCCZ - 0.5V 12.8 13.5 14.2 V 150 300 mV 14.6 V 1.3 1.7 mA 15 19 mA 12.4 Start-up Threshold VCCZ - 0.5 V Shutdown Threshold VCCZ - 3.5 V Shutdown Temperature (TJ) 120 C Hysteresis (TJ) 30 C FUNCTIONAL DESCRIPTION OVERVIEW The ML4831 consists of an Average Current controlled continuous boost Power Factor front end section with a flexible ballast control section. Start-up and lamp-out retry timing are controlled by the selection of external timing components, allowing for control of a wide variety of different lamp types. The ballast section controls the lamp power using frequency modulation (FM) with additional programmability provided to adjust the VCO frequency range. This allows for the IC to be used with a variety of different output networks. POWER FACTOR SECTION The ML4831 Power Factor section is an average current sensing boost mode PFC control circuit which is architecturally similar to that found in the ML4821. For detailed information on this control architecture, please refer to Application Note 16 and the ML4821 data sheet. GAIN MODULATOR The ML4831 gain modulator provides high immunity to the disturbances caused by high power switching. The rectified line input sine wave is converted to a current via a dropping resistor. In this way, small amounts of ground noise produce an insignificant effect on the reference to the PWM comparator. The output of the gain modulator appears on the positive terminal of the IA amplifier to form the reference for the current error amplifier. Please refer to Figure 1. VMUL where: [I(SINE) x (VEA - 1.1V)] 4.17mA (1) I(SINE) is the current in the dropping resistor, V(EA) is the output of the error amplifier (Pin 1). The output of the gain modulator is limited to 1.0V. 5 ML4831 AVERAGE CURRENT AND OUTPUT VOLTAGE REGULATION TRANSCONDUCTANCE AMPLIFIERS The PFC voltage feedback, PFC current sense, and the loop current amplifiers are all implemented as operational transconductance amplifiers. They are designed to have low small signal forward transconductance such that a large value of load resistor (R1) and a low value ceramic capacitor (<1F) can be used for AC coupling (C1) in the frequency compensation network. The compensation network shown in Figure 2 will introduce a zero and a pole at: The PWM regulator in the PFC Control section will act to offset the positive voltage caused by the multiplier output by producing an offsetting negative voltage on the current sense resistor at Pin 4. A cycle-by-cycle current limit is included to protect the MOSFET from high speed current transients. When the voltage at Pin 4 goes negative by more than 1V, the PWM cycle is terminated. For more information on compensating the average current and boost voltage error amplifier loops, see ML4821 data sheet. fZ = 1 2 R1C1 fP = 1 2 R1C2 (2) OVERVOLTAGE PROTECTION AND INHIBIT The OVP pin serves to protect the power circuit from being subjected to excessive voltages if the load should change suddenly (lamp removal). A divider from the high voltage DC bus sets the OVP trip level. When the voltage on Pin 18 exceeds 2.75V, the PFC transistors are inhibited. The ballast section will continue to operate. The OVP threshold should be set to a level where the power components are safe to operate, but not so low as to interfere with the boost voltage regulation loop. 18 - 2.5V + R1 C2 C1 Figure 2. Compensation Network 7 LFB OUT R(SET) OSC 10 16 17 11 2 R(X)/C(X) PREHEAT TIMER VREF - + -VMUL+ IA + S - PFC OUT Q 15 + -1V PWM (PFC) OUT A Q 14 + T GAIN MODULATORS I(SINE) OUT B Q 13 EA OUT - EA -/OVP 2.5V - + 2.75V + OVP Figure 1. ML4831 Block Diagram 6 8 R - 18 9 VREF R(T)/C(T) IA OUT 7K 1 INTERRUPT 5 GND - 3 LAMP F.B. - UNDER-VOLTAGE AND THERMAL SHUTDOWN 6 2.5V + VCC 7K 4 + P GND 12 ML4831 Figure 3 shows the output configuration for the operational transconductance amplifiers. CURRENT MIRROR IN OUT IQ + IQ - BALLAST OUTPUT SECTION The IC controls output power to the lamps via frequency modulation with non-overlapping conduction. This means that both ballast output drivers will be low during the discharging time tDIS of the oscillator capacitor CT. OSCILLATOR gmVIN 2 io = gmVIN gmVIN 2 The VCO frequency ranges are controlled by the output of the LFB amplifier (Pin 6). As lamp current decreases, Pin 6 rises in voltage, causing the C(T) charging current to decrease, thereby causing the oscillator frequency to decrease. Since the ballast output network attenuates high frequencies, the power to the lamp will be increased. 17 IN VREF VREF OUT CURRENT MIRROR CONTROL ICHG R(T) R(T)/C(T) + 8 Figure 3. Output Configuration 1.25/3.75 A DC path to ground or VCC at the output of the transconductance amplifiers will introduce an offset error. The magnitude of the offset voltage that will appear at the input is given by VOS = io/gm. For a io of 1uA and a gm of 0.08 mhos the input referred offset will be 12.5mV. Capacitor C1 as shown in Figure 2 is used to block the DC current to minimize the adverse effect of offsets. - C(T) 5 mA Slew rate enhancement is incorporated into all of the operational transconductance amplifiers in the ML4831. This improves the recovery of the circuit in response to power up and transient conditions. The response to large signals will be somewhat non-linear as the transconductance amplifiers change from their low to high transconductance mode. This is illustrated in Figure 4. CLOCK tDIS tCHG VTH = 3.75V iO C(T) VTL = 1.25V VIN Differential 0 Linear Slope Region Figure 5. Oscillator Block Diagram and Timing The oscillator frequency is determined by the following equations: FOSC = 1 t CHG + tDIS (3) and Figure 4. Transconductance Amplifier Characteristics V + I R - VTL t CHG = R T CT In REF CH T VREF + ICH R T - VTH (4) 7 ML4831 The oscillator's minimum frequency is set when ICH = 0 where: FOSC 1 0.51x R T CT (5) This assumes that tCHG >> tDIS. When LFB OUT is high, ICH = 0 and the minimum frequency occurs. The charging current varies according to two control inputs to the oscillator: To help reduce ballast cost, the ML4831 includes a temperature sensor which will inhibit ballast operation if the IC's junction temperature exceeds 120C. In order to use this sensor in lieu of an external sensor, care should be taken when placing the IC to ensure that it is sensing temperature at the physically appropriate point in the ballast. The ML4831's die temperature can be estimated with the following equation: TJ TA x PD x 65C / W (9) 1. The output of the preheat timer VCC VCCZ 2. The voltage at Pin 6 (lamp feedback amplifier output) V(ON) In preheat condition, charging current is fixed at ICHG (PREHEAT) = 2.5 R(SET) V(OFF) (6) In running mode, charging current decreases as the VPIN6 rises from 0V to VOH of the LAMP FB amplifier. The highest frequency will be attained when ICHG is highest, which is attained when VPIN6 is at 0V: ICHG(0) = 5 R(SET) In this condition, the minimum operating frequency of the ballast is set per (5) above. For the IC to be used effectively in dimming ballasts with higher Q output networks a larger CT value and lower RT value can be used, to yield a smaller frequency excursion over the control range (VPIN6). The discharge current is set to 5mA. Assuming that IDIS >> IRT: (8) IC BIAS, UNDER-VOLTAGE LOCKOUT AND THERMAL SHUTDOWN The IC includes a shunt regulator which will limit the voltage at VCC to 13.5 (VCCZ). The IC should be fed with a current limited source, typically derived from the ballast transformer auxiliary winding. When VCC is below VCCZ - 0.7V, the IC draws less than 1.7mA of quiescent current and the outputs are off. This allows the IC to start using a "bleed resistor" from the rectified AC line. 8 15mA 1.3mA (7) Highest lamp power, and lowest output frequency are attained when VPIN6 is at its maximum output voltage (VOH). tDIS(VCO) 490 x CT t ICC t Figure 6. Typical VCC and ICC Waveforms when the ML4831 is Started with a Bleed Resistor from the Rectified AC Line and Bootstrapped from an Auxiliary Winding. STARTING, RE-START, PREHEAT AND INTERRUPT The lamp starting scenario implemented in the ML4831 is designed to maximize lamp life and minimize ballast heating during lamp out conditions. The circuit in Figure 7 controls the lamp starting scenarios: Filament preheat and Lamp Out interrupt. C(X) is charged with a current of IR(SET)/4 and discharged through R(X). The voltage at C(X) is initialized to 0.7V (VBE) at power up. The time for C(X) to rise to 3.4V is the filament preheat time. During that time, the oscillator charging current (ICHG) is 2.5/R(SET). This will produce a high frequency for filament preheat, but will not produce sufficient voltage to ignite the lamp. After cathode heating, the inverter frequency drops to FMIN causing a high voltage to appear to ignite the lamp. If the voltage does not drop when the lamp is supposed to have ignited, the lamp voltage feedback coming into Pin 9 rises to above VREF, the C(X) charging current is shut off and the inverter is inhibited until C(X) is discharged by R(X) to the 1.2V threshold. Shutting off the inverter in this manner prevents the inverter from generating excessive heat when the lamp fails to strike or is out of socket. Typically this time is set to be fairly long by choosing a large value of R(X). ML4831 LFB OUT is ignored by the oscillator until C(X) reaches 6.8V threshold. The lamps are therefore driven to full power and then dimmed. The C(X) pin is clamped to about 7.5V. 0.625 R(SET) R(X)/C(X) + 10 HEAT C(X) 1.2/3.4 - A summary of the operating frequencies in the various operating modes is shown below. R(X) 6.8 + 1.2/6.8 - INHIBIT R 9 INT VREF - Operating Mode Operating Frequency Preheat [F(MAX) to F(MIN)] 2 Dimming Lock-out F(MIN) Dimming Control F(MIN) to F(MAX) DIMMING LOCKOUT Q S + Figure 7. Lamp Preheat and Interrupt Timers 6.8 3.4 R(X)/C(X) 1.2 .65 0 HEAT DIMMING LOCKOUT 7.5 INT INHIBIT Figure 8. Lamp Starting and Restart Timing 9 10 R14 C12 N G L C5 120V F1 D6 D5 L2 L1 R1 R4 C25 C2 C1 D2 R2 C26 C4 C3 D1 R3 R5 R6 D4 D3 C6 3 1 R24 D8 2 4 11 10 9 C7 12 13 14 15 16 17 18 C10 + 8 ML4831 7 6 5 4 3 2 1 R16 R10 R17 T1 R7 + C13 R15 R9 R11 + + R13 R12 C15 C16 R8 C11 C14 C24 Q1 D7 R21 C17 8 5 T2 D11 Q3 R22 4 1 Q2 10 7 6 8 D12 T3 4 2 C22 5 1 3 C19 9 4 1 5 8 R23 C20 T4 T5 8 1 C21 D13 5 4 C23 B B R R Y Y ML4831 APPLICATIONS POWER FACTOR CORRECTED FLUORESCENT DIMMING LAMP BALLAST Figure 9. Typical Application: 2-Lamp Isolated Dimming Ballast with Active Power Factor Correction for 120VAC Input ML4831 TABLE 1: PARTS LIST FOR THE ML4831EVAL EVALUATION KIT CAPACITORS QTY. REF. DESCRIPTION MFR. PART NUMBER 2 C1, 2 3.3nF, 125VAC, 10%, ceramic, "Y" capacitor Panasonic ECK-DNS332ME 1 C3 0.33F, 250VAC, "X", capacitor Panasonic ECQ-U2A334MV 4 C4, 8, 9, 22 0.1F, 50V, 10%, ceramic capacitor AVX SR215C104KAA 2 C5, 21 0.01F, 50V, 10%, ceramic capacitor AVX SR211C103KAA 1 C6 1.5F, 50V, 2.5%, NPO ceramic capacitor AVX RPE121COG152 2 C7, 12 1F, 50V, 20%, ceramic capacitor AVX SR305E105MAA 1 C10 100F, 25V, 20%, electrolytic capacitor Panasonic ECE-A1EFS101 1 C11 100F, 250V, 20%, electrolytic capacitor Panasonic ECE-S2EG101E 1 C13 4.7F, 50V, 20%, electrolytic capacitor Panasonic ECE-A50Z4R7 3 C14, 15, 17 0.22F, 50V, 10%, ceramic capacitor AVX SR305C224KAA 1 C16 1.5F, 50V, 10%, ceramic capacitor AVX SR151V152KAA 1 C19 22nF, 630V, 5%, polypropylene capacitor WIMA MKP10, 22nF, 630V, 5% 1 C20 0.1F, 250V, 5%, polypropylene capacitor WIMA MKP10, 0.1F, 250V, 5% 1 C23 0.068F, 160V, 5%, polypropylene capacitor WIMA MKP4, 68nF, 160V, 5% 1 C24 220F, 16V, 20%, electrolytic capacitor Panasonic 1 C25 47nF, 50V, 10%, ceramic capacitor AVX SR211C472KAA 1 C26 330pF, 50V, 10%, ceramic capacitor AVX SR151A331JAA ECE-A16Z220 RESISTORS: 1 R1 0.33, 5%, 1/2W, metal film resistor NTE HWD33 1 R2 4.3K, 1/4W, 5%, carbon film resistor Yageo 4.3K-Q 1 R3 47K, 1/4W, 5%, carbon film resistor Yageo 47K-Q 1 R4 12K, 1/4W, 5%, carbon film resistor Yageo 12K-Q 1 R5 20K, 1/4W, 1%, metal film resistor Dale 1 R6 360K, 1/4W, 5%, carbon film resistor Yageo 360K-Q 1 R7 36K, 1W, 5%, carbon film resistor Yageo 36KW-1-ND 3 R8, 22, 11 22, 1/4W, 5%, carbon film resistor Yageo 22-Q 1 R9 402K, 1/4W, 1%, metal film resistor Dale SMA4-402K-1 1 R10 17.8K, 1/4W, 1%, metal film resistor Dale SMA4-17.8K-1 1 R12 475K, 1/4W, 1%, metal film resistor Dale SMA4-475K-1 1 R13 5.49K, 1/4W, 1%, metal film resistor Dale SMA4-5.49K-1 SMA4-20K-1 11 ML4831 TABLE 1: PARTS LIST FOR ML4831EVAL EVALUATION KIT (Continued) RESISTORS: (Continued) QTY. REF. DESCRIPTION MFR. PART NUMBER 4 R14, 17, 24, 25 100K, 1/4W, 5%, carbon film resistor Yageo 100K-Q 1 R15 681K, 1/4W, 5%, carbon film resistor Yageo 681K-Q 1 R16 10K, 1/4W, 1%, metal film resistor Dale 1 R21 33, 1/4W, 5%, carbon film resistor Yageo 33-Q 1 R23 25K, pot (for dimming adjustment) Bourns 3386P-253-ND SMA4-10K-1 DIODES: 4 D1, 2, 3, 4 1A, 600V, 1N4007 diode (or 1N5061 as a substitute) Motorola 1N4007TR 2 D5, 6 1A, 50V (or more), 1N4001 diodes Motorola 1N4001TR 1 D7 3A, 400V, BYV26C or BYT03 400 fast recovery or MUR440 Motorola ultra Fast diode GI 5 D8, 9, 11, 12, 13 0.1A, 75V, 1N4148 signal diode Motorola 1N4148TR IC1 ML4831, Electronic Ballast Controller IC Micro Linear ML4831CP 3.3A, 400V, IRF720 power MOSFET IR BYV26C IC's: 1 TRANSISTORS: 3 Q1, 2, 3 IR720 MAGNETICS: 1 T1 T1 Boost Inductor, E24/25, 1mH, Custom Coils P/N 5039 or Coiltronics P/N CTX05-12538-1 E24/25 core set, TDK PC40 material 8-pin vertical bobbin (Cosmo #4564-3-419), Wind as follows: 195 turns 25AWG magnet wire, start pin #1, end pin #4 1 layer mylar tape 14 turns 26AWG magnet wire, start pin #3, end pin #2 NOTE: Gap for 1mH 5% 1 T2 T2 Gate Drive Xfmr, LPRI = 3mH, Custom Coils P/N 5037 or Coiltronics P/N CTX05-12539-1 Toroid Magnetics YW-41305-TC Wind as follows: Primary = 25 turns 30AWG magnet wire, start pin #1, end pin #4 Secondary = 50 turns 30AWG magnet wire, start pin #5, end pin #8 12 ML4831 TABLE 1: PARTS LIST FOR ML4831EVAL EVALUATION KIT (Continued) MAGNETICS: (Continued) QTY. REF. DESCRIPTION MFR. PART NUMBER 1 T3 T3 Inductor, LPRI = 1.66mH, Custom Ciols P/N 5041 or Coiltronics P/N CTX05-12547-1 E24/25 core set, TDK PC40 material 10 pin horizontal bobbin (Plastron #0722B-31-80) Wind as follows: 1st: 170T of 25AWG magnet wire; start pin #10, end pin #9. 1 layer of mylar tape 2nd: 5T of #32 magnet wire; start pin #2, end pin #1 1 layer of mylar tape 3rd: 3T of #30 Kynar coated wire; start pin #4, end pin #5 4th: 3T of #30 Kynar coated wire; start pin #3, end pin #6 5th: 3T of #30 Kynar coated wire; start pin #7, end pin #8 NOTE: Gap for 1.66mH 5% (pins 9 to 10) 1 T4 T4 Power Xfmr, LPRI = 3.87mH, Custom Ciols P/N 5038 or Coiltronics P/N CTX05-12545-1 E24/25 core set, TDK PC40 material 8 pin vertical bobbin (Cosmo #4564-3-419) Wind as follows: 1st: 200T of 30AWG magnet wire; start pin #1, end pin #4. 1 layer of mylar tape 2nd: 300T of 32AWG magnet wire; start pin #5, end pin #8 NOTE: Gap for inductance primary: (pins 1 to 4) @ 3.87mH 5% 1 T5 T5 Current Sense Inductor, Custom Coils P/N 5040 or Coiltronics P/N CTX05-12546-1 Toroid Magnetics YW-41305-TC Wind as follows: Primary = 3T 30AWG magnet coated wire, start pin #1, end pin #4 Secondary = 400T 35AWG magnet wire, start pin #5, end pin #8 INDUCTORS: 2 L1, 2 EMI/RFI Inductor, 600H, DC resistance = 0.45 Prem. Magnetics SPE116A F1 2A fuse, 5 x 20mm miniature F948-ND FUSES: 1 2 Littlefuse Fuse Clips, 5 x 20mm, PC Mount F058-ND HARDWARE: 1 Single TO-220 Heatsink Aavid Eng. PB1ST-69 2 Double TO-220 Heatsink IERC PSE1-2TC 3 MICA Insulators Keystone 4673K-ND 13 ML4831 PHYSICAL DIMENSIONS inches (millimeters) Package: P18 18-Pin PDIP 0.890 - 0.910 (22.60 - 23.12) 18 0.240 - 0.260 0.295 - 0.325 (6.09 - 6.61) (7.49 - 8.26) PIN 1 ID 0.045 MIN (1.14 MIN) (4 PLACES) 1 0.050 - 0.065 (1.27 - 1.65) 0.100 BSC (2.54 BSC) 0.015 MIN (0.38 MIN) 0.170 MAX (4.32 MAX) 0.125 MIN (3.18 MIN) 0.016 - 0.022 (0.40 - 0.56) SEATING PLANE 0.008 - 0.012 (0.20 - 0.31) 0 - 15 ORDERING INFORMATION PART NUMBER ML4831CP TEMPERATURE RANGE 0C to 85C PACKAGE Molded PDIP (P18) (END OF LIFE) (c) Micro Linear 1997 Micro Linear is a registered trademark of Micro Linear Corporation Products described in this document may be covered by one or more of the following patents, U.S.: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; 5,508,570; 5,510,727; 5,523,940; 5,546,017; 5,559,470; 5,565,761; 5,592,128; 5,594,376; Japan: 2598946. Other patents are pending. Micro Linear reserves the right to make changes to any product herein to improve reliability, function or design. Micro Linear does not assume any liability arising out of the application or use of any product described herein, neither does it convey any license under its patent right nor the rights of others. The circuits contained in this data sheet are offered as possible applications only. Micro Linear makes no warranties or representations as to whether the illustrated circuits infringe any intellectual property rights of others, and will accept no responsibility or liability for use of any application herein. The customer is urged to consult with appropriate legal counsel before deciding on a particular application. 14 2092 Concourse Drive San Jose, CA 95131 Tel: 408/433-5200 Fax: 408/432-0295 DS4831-01