Product Summary

The UC3843 is a current mode pwm controller. It provides the necessary features to implement off-line or DC to DC fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits of the UC3843 include under voltage lock out featuring start-up current less than 1mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched operation, the UC3843 also provides current limit control, and a totem pole output stage designed to source or sink high peakcurrent.

Parametrics

UC3843 absolute maximum ratings: (1)Vi Supply Voltage (low impedance source): 30 V; (2)IO Output Current: ±1 A; (3)EO Output Energy (capacitive load): 5 mJ; (4)Analog Inputs (pins 2, 3): -0.3 to 6.3 V; (5)Error Amplifier Output Sink Current: 10 mA; (6)Ptot Power Dissipation at Tamb ≤ 50 ℃ (minidip, DIP-14): 1 W; (7)Ptot Power Dissipation at Tamb ≤ 25 ℃ (SO14): 725 mW; (8)Tstg Storage Temperature Range: -65 to 150 ℃; (9)TL Lead Temperature (soldering 10s): 300 ℃.

Features

UC3843 features: (1)optimized for off-line and dc to dc converters; (2)lowstart-up current (< 1 ma); (3)automatic feed forward compensation; (4)pulse-by-pulsecurrent limiting; (5)enhanced load response characteristics; (6)under-voltage lockout with hysteresis; (7)double pulse suppression; (8)high current totem pole output; (9)internally trimmed bandgap reference; (10)500 khz operation; (11)low Ro erroramp.

Diagrams

UC3843 block diagram

Image Part No Mfg Description Data Sheet Download Pricing
(USD)
Quantity
UC3843
UC3843

Other


Data Sheet

Negotiable 
UC3843A
UC3843A

Other


Data Sheet

Negotiable 
UC3843AD
UC3843AD

Texas Instruments

Current Mode PWM Controllers Current Mode

Data Sheet

0-1: $0.85
1-25: $0.76
25-100: $0.67
100-250: $0.59
UC3843AD1
UC3843AD1

ON Semiconductor

Other Power Management 52kHz 1A Current PWM

Data Sheet

Negotiable 
UC3843AD1013TR
UC3843AD1013TR


IC REG CTRLR BST FLYBK ISO 8SOIC

Data Sheet

Negotiable 
UC3843AD1G
UC3843AD1G

ON Semiconductor

Other Power Management 52kHz 1A Current PWM w/96% Duty Cycle Max

Data Sheet

Negotiable 
UC3843AD1R2
UC3843AD1R2

ON Semiconductor

Other Power Management 52kHz 1A Current PWM

Data Sheet

Negotiable 
UC3843AD1R2G
UC3843AD1R2G

ON Semiconductor

Other Power Management 52kHz 1A Current PWM w/96% Duty Cycle Max

Data Sheet

Negotiable