UNISONIC TECHNOLOGIES CO., LTD UC3846 LINEAR INTEGRATED CIRCUIT CURRENT MODE PWM CONTROLLER DIP-16 DESCRIPTION The UTC UC3846 control IC offers all necessary features for accomplishment of fixed frequency, current mode control functions, however it contains the least external parts. The performance of this technique is superior to the others in better line regulation, enhanced load response characteristics while designing a simpler and easier control loop for design. It owns topological advantages of inherent pulse-by-pulse current limiting, automatic symmetry correction for push-pull converters, and the ability to parallel “power modules" for equal current sharing. Protection loop includes soft start, built-in under-voltage lockout and programmable current limit. The shutdown circuitry can provide either a complete shutdown with automatic restart or the supply off-latch. In addition, many other features can also be available, including fully latched operation, double pulse suppression, deadline adjust, and a ±1% trimmed bandgap reference. The UTC UC3846 features low outputs in the OFF state. SOP-16W FEATURES * Built-in under-voltage lockout * Soft start * Shutdown function * 500kHZ operation * Feed forward compensation * ±1% bandgap reference * Programmable pulse-by-pulse current limiting SOP-16 * Improved load response characteristics * Parallel operation capability for modular power systems * Differential current sense amplifier with wide common mode range * Double pulse suppression * 500mA (Peak) totem-pole outputs * Automatic symmetry correction in push-pull configuration ORDERING INFORMATION Ordering Number Lead Free Halogen Free UC3846L-D16-T UC3846G-D16-T UC3846L-S16-T UC3846G-S16-T UC3846L-S16-R UC3846G-S16-R UC3846L-S16W-T UC3846G-S16W-T UC3846L-S16W-R UC3846G-S16W-R www.unisonic.com.tw Copyright © 2013 Unisonic Technologies Co., Ltd Package Packing DIP-16 SOP-16 SOP-16 SOP-16W SOP-16W Tube Tube Tape Reel Tube Tape Reel 1 of 9 QW-R103-061. C UC3846 LINEAR INTEGRATED CIRCUIT PIN CONFIGURATION C/S SS 1 16 Shutdown VREF 2 15 VIN C/S- 3 14 C/S+ 4 13 VC E/A+ 5 12 GND E/A- 6 11 A Out COMP 7 10 Sync CT 8 9 B Out RT PIN DESCRIPTION PIN NO. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 PIN NAME C/S SS VREF C/SC/S+ E/A+ E/ACOMP CT RT SYNC A OUT GND VC B OUT VIN SHUTDOWN DESCRIPTION Adjustment of Current Limiting Internal Reference Voltage Forward Input of Current Limiting Backward Input of Current Limiting Forward Input of Error Amplifier Backward Input of Error Amplifier Output of Error Amplifier External Capacity for Frequency External Resistor for Frequency Synchronization for Frequency of Oscillator Dual Output A Ground Power Supply of the Collector Dual Output B DC Power Supply Input Shutdown Controller UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 9 QW-R103-061. C UC3846 LINEAR INTEGRATED CIRCUIT BLOCK DIAGRAM VIN 15 2 VREF SYNC 10 T OSC CT 8 C/S- 3 - C/S+ 4 + Q Q 11 A OUT 14 B OUT 12 GND DUAL + - COMP SR Q S 0.5V E/A- 6 VC OUTPUT A E/A+ 5 13 UVLO LOCKOUT RT 9 VREF + EA - 0.5mA 1 + - COMP 7 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 350mV 16 C/S SS SHUTDOWN 6KΩ 3 of 9 QW-R103-061. C UC3846 LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATING (Note) PARAMETER SYMBOL RATINGS UNIT Supply Voltage (Pin 15) VIN +40 V Collector Supply Voltage (Pin 13) VC +40 V Output Current, Source or Sink (Pins 11, 14) IO 500 mA Analog Inputs (Pins 3, 4, 5, 6, 16) VA -0.3~+VIN V Reference Output Current (Pin 2) IREF -30 mA Sync Output Current (Pin 10) ISYNC-OUT -5 mA Error Amplifier Output Current (Pin 7) IO-EA -5 mA Soft Start Sink Current (Pin 1) ISINK 50 mA Oscillator Charging Current (Pin 9) IOSC 5 mA TA=25°C 1000 mW Power Dissipation PD TC=25°C 2000 mW Storage Temperature TSTG -65~+150 °C Note: 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. ELECTRICAL CHARACTERISTICS (TJ=TA=0°C~+70°C, VIN=15V, RT=10k, CT=4.7nF, Unless otherwise specified) PARAMETER REFERENCE SECTION Output Voltage Line Regulation Load Regulation Temperature Stability Total Output Variation Output Noise Voltage Long Term Stability Short Circuit Output Current OSCILLATOR SECTION Initial Accuracy Voltage Stability Temperature Stability Sync Output High Level Sync Output Low Level Sync Input High Level Sync Input Low Level Sync Input Current ERROR AMP SECTION Input Offset Voltage Input Bias Current Input Offset Current Common Mode Range Open Loop Voltage Gain Unity Gain Bandwidth CMRR PSRR Output Sink Current Output Source Current High Level Output Voltage Low Level Output Voltage SYMBOL VREF ∆V1 ∆V2 VS VREF-O VN ∆V3 IS FOSC ∆V ∆TS VOH(SYNC) VOL(SYNC) VIH(SYNC) VIL(SYNC) ISYNC VIO IBIAS IIO VCM GVO B CMRRA PSRRA ISINK ISOURCE VOH VOL TEST CONDITIONS TJ=25°C, IO=1mA VIN=8V~40V IL=1mA~10mA Over Operating Range, (Note 2) Line, Load, and Temperature (Note 2) 10Hz≤f≤10kHz, TJ=25°C (Note 2) TJ=125°C, 1000 Hrs. (Note 2) VREF=0V TJ=25°C VIN=8V~40V Over Operating Range (Note 2) TYP 5.0 5.1 5 3 0.4 4.95 -10 39 3.9 Pin 8=0V Pin 8=0V Sync Voltage=3.9V, Pin 8=0V 100 5 -45 VIN=8V~40V ∆VO=1.2~3V, VCM=2V TJ=25°C (Note 2) VCM=0V~38V, VIN=40V VIN=8V~40V VID=-15mV~-5V, VPIN 7=1.2V VID=15mV~5V, VPIN 7=2.5V RL=(Pin 7) 15kΩ MAX UNIT 5.2 20 15 V mV mV mV/°C 5.25 V µV mV mA 43 -1 -1 4.35 2.3 47 2 2.5 1.3 2.5 1.5 kHz % % V V V V mA 3.9 0.5 -0.6 40 UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw MIN 0 80 0.7 75 80 2 -0.2 4.3 105 1.0 100 105 6 -0.5 4.6 0.7 10 -2 250 VIN-2V 1 mV µA nA V dB MHz dB dB mA mA V V 4 of 9 QW-R103-061. C UC3846 LINEAR INTEGRATED CIRCUIT ELECTRICAL CHARACTERISTICS(Cont.) PARAMETER SYMBOL CURRENT SENSE AMPLIFIER SECTION Amplifier Gain GA Maximum Differential Input VIN(MAX) Signal (VPIN 4-VPIN 3) Input Offset Voltage VIO CMRR CMRRA PSRR PSRRA Input Bias Current IBIAS Input Offset Current IIO Input Common Mode Range ∆VR Delay to Outputs tD CURRENT LIMIT ADJUST SECTION Current Limit Offset VL TEST CONDITIONS MIN TYP VPIN 3=0V, Pin 1 Open (Note 3, 4) 2.5 2.75 Pin 1 Open (Note 3), RL (Pin 7)=15kW 1.1 1.2 VPIN 1=0.5V, Pin 7 Open (Note 3) VCM=1V~12V VIN=8V~40V VPIN 1=0.5V, Pin 7 Open (Note 3) VPIN 1=0.5V, Pin 7 Open (Note 3) 60 60 5 83 84 -2.5 0.08 VPIN 3=0V, VPIN 4=0V, Pin 7 Open (Note 3) VPIN 5=VREF,VPIN 6=0V 0.45 3.0 V V 200 -10 1 VIN-3 500 mV dB dB µA µA V ns 0.5 0.55 V 0 TJ=25°C, (Note 2) MAX UNIT 25 Input Bias Current IB -10 -30 µA SHUTDOWN TERMINAL SECTION Threshold Voltage VTH 250 350 550 mV Input Voltage Range ∆VSHUT 0 VIN V Minimum Latching Current ILATCH (Note 6) 3.0 1.5 mA (IPIN 1) Maximum Non-Latching INONLATCH (Note 7) 1.5 0.8 mA Current (IPIN 1) Delay to Outputs tD-SHUT TJ=25°C (Note 2) 300 600 ns OUTPUT SECTION Collector-Emitter Voltage VT 40 V Collector Leakage Current IL VC=40V (Note 5) 200 µA VOL1 ISINK=20mA 0.1 0.4 V Output Low Level VOL2 ISINK=100mA 0.4 2.1 V VOH1 ISOURCE=20mA 13 13.5 V Output High Level VOH2 ISOURCE=100mA 12 13.2 V Rise Time tR CL=1nF, TJ=25°C (Note 2) 50 300 ns Fall Time tF CL=1nF, TJ=25°C (Note 2) 50 300 ns UNDER-VOLTAGE LOCKOUT SECTION Start-Up Threshold VSTART 7.7 8.0 V Threshold Hysteresis VH 0.75 V TOTAL STANDBY CURRENT Supply Current IT 17 21 mA Notes: 1. All voltages are with respect to Ground, Pin 13. Currents are positive into, negative out of the speficied terminal. 2. These parameters are not 100% tested in production, although guaranteed over the recommended operating conditions 3. Parameter measured at trip point of latch with VPIN 5=VREF, VPIN 6=0V. ∆VPIN7 4. Amplifier gain defined as: G= , VPIN4=0~1.0V ∆VPIN4 5. Applies to UTC UC3846 only due to polarity of outputs. 6. Current into Pin 1 guaranteed to latch circuit in shutdown state. 7. Current into Pin 1 guaranteed not to latch circuit in shutdown state. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 5 of 9 QW-R103-061. C UC3846 LINEAR INTEGRATED CIRCUIT TEST CIRCUIT IS RS (+)4 ISENSE (-)3 A + VREF 0.5mA 0.5V R1 1 EA Current Limit R2 Comp - Comp 7 Peak Current (Is) is determined by the formula: IS= UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw R2 VREF -0.5 R1+R2 3RS 6 of 9 QW-R103-061. C UC3846 LINEAR INTEGRATED CIRCUIT TEST CIRCUIT(Cont.) VREF ISENSE Comp R1 1 Current Limit * C 0.5 S S EA R2 VREF 16 Shutdown - + + 350mV Shutdown With Auto-Restart Current Limit (Pin 1) 0.5V Shutdown Without Auto-Restart (Latched) 0 Shutdown (Pin 16) ON OFF PWM VREF < 0.8mA R1 If VREF < 0.8mA, the shutdown latch will commutate when R1 ISS=0.8mA and a restart cycle will be initiated. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw VREF (Latched Off) R1 > 3mA VREF If R1 > 3mA, the device will latch off until power is recycled. 7 of 9 QW-R103-061. C UC3846 LINEAR INTEGRATED CIRCUIT TYPICAL APPLICATION CIRCUIT UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 8 of 9 QW-R103-061. C UC3846 TYPICAL CHARACTERISTICS Rising Time Falling Time VIN&VDD=15V,AOUT=1nF, CT=4.7nF, RT=10KΩ, output fall time from 90%~ 10%. 5V/di v 5V/div VIN&VDD=15V, AOUT=1nF, CT=4.7nF, RT=10KΩ, output rise time from 10%~ 90%. 0 0 0 500 Time (100ns/div) 1000 0 Voltage Stability VIN=8V, CT=4.7nF, RT=10KΩ 0 0 50 Time (10µs/div) 500 Time (100ns/div) 1000 Voltage Stability VIN=40V, CT=4.7nF, RT=10KΩ, no effect on the frequency 1V/di v 1V/div LINEAR INTEGRATED CIRCUIT 0 100 0 50 Time (10µs/div) 100 UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 9 of 9 QW-R103-061. C