Product Summary

The UC3844N is a control IC. The UC3844N 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 include under-voltage lockout featuring start up current less than 1mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The output stage of the UC3844N, suitable for driving N Channel MOSFETs, is low in the off state.

Parametrics

UC3844N absolute maximum ratings: (1)Supply Voltage (Low Impedance Source):30V; (2)Supply Voltage (ICC < 30mA): Self Limiting; (3)Output Current:±1A; (4)Output Energy (Capacitive Load): 5 μJ; (5)Analog Inputs (Pins 2, 3): -0.3V to +6.3V; (6)Error Amp Output Sink Current: 10 mA; (7)Power Dissipation at TA ≤ 25℃ (DIL8): 1 W; (8)Power Dissipation at TA ≤ 25℃ (SOIC-14): 725 mW; (9)Storage Temperature Range: -65 to +150℃; (10)Junction Temperature Range: -55 to +150℃; (11)Lead Temperature (soldering, 10 seconds): 300℃.

Features

UC3844N features: (1)Optimized For Off-line And DC To DC Converters; (2)Low Start Up Current (<1mA); (3)utomatic Feed Forward Compensation; (4)Pulse-by-pulse Current 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)500khz Operation; (11)Low RO Error Amp.

Diagrams

UC3844N block diagram

Image Part No Mfg Description Data Sheet Download Pricing
(USD)
Quantity
UC3844NG4
UC3844NG4

Texas Instruments

Current Mode PWM Controllers Current-Mode PWM Controller

Data Sheet

0-1: $0.85
1-25: $0.76
25-100: $0.67
100-250: $0.59
UC3844N
UC3844N

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
UC3844NG
UC3844NG

ON Semiconductor

Other Power Management 52kHz 1A Current PWM w/48% Duty Cycle Max

Data Sheet

Negotiable