UC3843AD1013TR STMicroelectronics, UC3843AD1013TR Datasheet
UC3843AD1013TR
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UC3843AD1013TR Summary of contents
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HIGH PERFORMANCE CURRENT MODE PWM CONTROLLER . TRIMMED OSCILLATOR DISCHARGE CUR- . RENT . CURRENT MODE OPERATION TO 500kHz AUTOMATIC FEED FORWARD COMPENSA- . TION LATCHING PWM FOR CYCLE-BY-CYCLE . CURRENT LIMITING INTERNALLY TRIMMED REFERENCE WITH . UNDERVOLTAGE LOCKOUT ...
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UC2842A/3A/4A/5A - UC3842A/3A/4A/5A ABSOLUTE MAXIMUM RATINGS Symbol V Supply Voltage (low impedance source Supply Voltage (Ii < 30mA Output Current O E Output Energy (capacitive load) O Analog Inputs (pins 2, 3) Error Amplifier Output Sink ...
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THERMAL DATA Symbol R Thermal Resistance Junction-ambient. th j-amb ELECTRICAL CHARACTERISTICS ( [note 1] Unless otherwise stated, these specifications apply for -25 < T < for UC284XA; 0 < T amb Symbol Parameter REFERENCE SECTION V Output Voltage ...
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UC2842A/3A/4A/5A - UC3842A/3A/4A/5A ELECTRICAL CHARACTERISTICS (continued) Symbol Parameter OUTPUT SECTION V Output Low Level OL V Output High Level OH V UVLO Saturation OLS t Rise Time r t Fall Time f UNDER-VOLTAGE LOCKOUT SECTION Start Threshold Min Operating Voltage ...
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Figure 1: Open Loop Test Circuit. 4.7K 2N2222 100K ERROR AMP. ADJUST 1K I 4.7K SENSE ADJUST 5K D95IN343 High peak currents associated with capacitive loads necessitate careful grounding techniques. Timing and bypass capacitors should be connected close Figure 2: ...
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UC2842A/3A/4A/5A - UC3842A/3A/4A/5A Figure 4: Oscillator Discharge Current vs. Tem- perature. I dischg (mA) 8.5 8.0 7.5 7.0 -55 - Figure 6: Current Sense Input Threshold vs. Er- ror Amp Output Voltage (V) V =15V ...
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Figure 9: Output Saturation Voltage vs. Load Current. V sat (V) Source Saturation V i (Load to Ground =25˚ =15V Pulsed Load 120Hz Rate 3 T =-40˚ Sink Saturation ...
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UC2842A/3A/4A/5A - UC3842A/3A/4A/5A Figure 14 : Error Amp Configuration Figure 15 : Under Voltage Lockout. 7 ON/OFF COMMAND OFF Figure 16 : Current Sense Circuit . CURRENT ...
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Figure 17 : Slope Compensation Techniques. V REG SLOPE SENSE R S Figure 18 : Isolated MOSFET Drive and Current Transformer Sensing ...
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UC2842A/3A/4A/5A - UC3842A/3A/4A/5A Figure 19 : Latched Shutdown. 2N 3905 SCR must be selected for a holding current of less than 0.5mA at T The simple two transistor circuit can be used in place of the SCR as shown. All ...
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Figure 21: External Clock Synchronization. EXTERNAL SYNC INPUT 0.01 F The diode clamp is required if the Sync amplitude is large enough to cause the bottom side Figure 22: External Duty Cycle Clamp and Multi Unit Synchronization. ...
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UC2842A/3A/4A/5A - UC3842A/3A/4A/5A Figure 23: Soft-Start Circuit Figure 24: Soft-Start and Error Amplifier Output Duty Cycle Clamp BC109 V CLAMP 12/15 R BIAS R ...
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DIM. MIN. TYP. MAX. MIN. A 1.75 a1 0.1 0.25 0.004 a2 1.65 a3 0.65 0.85 0.026 b 0.35 0.48 0.014 b1 0.19 0.25 0.007 C 0.25 0.5 0.010 c1 45 (typ.) D (1) 4.8 5.0 0.189 E 5.8 ...
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UC2842A/3A/4A/5A - UC3842A/3A/4A/5A mm DIM. MIN. TYP. MAX. A 3.32 a1 0.51 0.020 B 1.15 1.65 0.045 b 0.356 0.55 0.014 b1 0.204 0.304 0.008 D 10.92 E 7.95 9.75 0.313 e 2.54 e3 7.62 e4 7.62 F 6.6 I ...
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... No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMi- croelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics ...