Product Summary

The UC3842BD is a high performance fixed frequency current mode controller. They are specifically designed for Off–Line and dc-to-dc converter applications offering the designer a cost–effective solution with minimal external components. These integrated circuits feature a trimmed oscillator for precise duty cycle control, a temperature compensated reference, high gain error amplifier, current sensing comparator, and a high current totem pole output ideally suited for driving a power MOSFET. The UC3842BD has UVLO thresholds of 16 V (on) and 10 V (off), ideally suited for off–line converters.

Parametrics

UC3842BD absolute maximum ratings: (1)Total Power Supply and Zener Current: 30 mA; (2)Output Current, Source or Sink (Note 1): 1.0 A; (3)Output Energy (Capacitive Load per Cycle): 5.0 μJ; (4)Current Sense and Voltage Feedback Inputs: -0.3 to + 5.5 V; (5)Error Amp Output Sink Current: 10 mA.

Features

UC3842BD features: (1)Trimmed Oscillator for Precise Frequency Control; (2)Oscillator Frequency Guaranteed at 250 kHz; (3)Current Mode Operation to 500 kHz; (4)Automatic Feed Forward Compensation; (5)Latching PWM for Cycle–By–Cycle Current Limiting; (6)Internally Trimmed Reference with Undervoltage Lockout; (7)High Current Totem Pole Output; (8)Undervoltage Lockout with Hysteresis; (9)Low Startup and Operating Current.

Diagrams

UC3842BD Simplified Block Diagram 

Image Part No Mfg Description Data Sheet Download Pricing
(USD)
Quantity
UC3842BD
UC3842BD

ON Semiconductor

Current Mode PWM Controllers 52kHz 1A Current PWM

Data Sheet

Negotiable 
UC3842BD1
UC3842BD1

STMicroelectronics

Current Mode PWM Controllers PWM CONTROLLER

Data Sheet

0-1650: $0.24
UC3842BD1013TR
UC3842BD1013TR

STMicroelectronics

Current Mode PWM Controllers 0.5mA Current Mode

Data Sheet

0-1: $0.34
1-10: $0.30
10-100: $0.26
100-250: $0.24
UC3842BD1G
UC3842BD1G

ON Semiconductor

Current Mode PWM Controllers 52kHz 1A Current PWM w/96% Duty Cycle Max

Data Sheet

0-1: $0.37
1-25: $0.32
25-100: $0.23
100-500: $0.20
UC3842BD1R2
UC3842BD1R2

ON Semiconductor

Current Mode PWM Controllers 52kHz 1A Current PWM

Data Sheet

Negotiable 
UC3842BD1R2G
UC3842BD1R2G

ON Semiconductor

Current Mode PWM Controllers 52kHz 1A Current PWM w/96% Duty Cycle Max

Data Sheet

0-1: $0.37
1-25: $0.32
25-100: $0.23
100-500: $0.20
UC3842BDG
UC3842BDG

ON Semiconductor

Current Mode PWM Controllers 52kHz 1A Current PWM w/96% Duty Cycle Max

Data Sheet

0-1: $0.37
1-25: $0.32
25-100: $0.23
100-500: $0.20
UC3842BDR2
UC3842BDR2

ON Semiconductor

Current Mode PWM Controllers 52kHz 1A Current PWM

Data Sheet

Negotiable