Product Summary

The UC2845N is a high performance fixed frequency current mode controller. It is 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 of UC2845N feature an oscillator, 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.

Parametrics

UC2845N absolute maximum ratings: (1)Total Power Supply and Zener Current: 30 mA; (2)Output Current, Source or Sink: 1.0 A; (3)Output Energy (Capacitive Load per Cycle): 5.0 mJ; (4)Current Sense and Voltage Feedback Inputs: – 0.3 to + 5.5 V; (5)Error Amp Output Sink Current: 10 mA; (6)Power Dissipation and Thermal Characteristics: D Suffix, Plastic Package, Case 751A, Maximum Power Dissipation @ TA = 25℃: 862 mW, N Suffix, Plastic Package, Case 626, Maximum Power Dissipation @ TA = 25℃: 1.25 W; (7)Operating Junction Temperature: + 150 ℃; (8)Operating Ambient Temperature: 0 to + 70 ℃; (9)Storage Temperature Range: – 65 to + 150 ℃.

Features

UC2845N features: (1)Current Mode Operation to 500 kHz Output Switching Frequency; (2)Output Deadtime Adjustable from 50% to 70%; (3)Automatic Feed Forward Compensation; (4)Latching PWM for Cycle-By-Cycle Current Limiting; (5)Internally Trimmed Reference with Undervoltage Lockout; (6)High Current Totem Pole Output; (7)Input Undervoltage Lockout with Hysteresis; (8)Low Startup and Operating Current; (9)Direct Interface with Motorola SENSEFET Products.

Diagrams

UC2845N Simplified block diagram

Image Part No Mfg Description Data Sheet Download Pricing
(USD)
Quantity
UC2845N
UC2845N

Texas Instruments

Current Mode PWM Controllers Current Mode

Data Sheet

0-1: $0.98
1-25: $0.85
25-100: $0.77
100-250: $0.68
UC2845NG4
UC2845NG4

Texas Instruments

Current Mode PWM Controllers Current-Mode PWM Controller

Data Sheet

0-1: $0.98
1-25: $0.85
25-100: $0.77
100-250: $0.68
UC2845NG
UC2845NG

ON Semiconductor

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

Data Sheet

Negotiable