UC3845AD

The UC3845AD is a fixed-frequency current-mode PWM controller IC designed for use in switch-mode power supplies and converters. It provides precise control over output voltage and current regulation in various power applications.

Pinout

(Note: The pin configuration below is a general representation. Refer to the specific datasheet for precise details.)

• VCC: Positive Power Supply
• CS: Current Sense Input
• RT/CT: Oscillator Timing Components
• GND: Ground
• COMP: Error Amplifier Output
• FB: Feedback Input
• SD: Shutdown Pin
• OUT: PWM Output
• SYNC: Synchronization Input
• VREF: Reference Voltage Output
• RT/CT: Oscillator Timing Components
• ERRORAMP: Error Amplifier Input

Circuit Diagram

Include a circuit diagram illustrating the connections and operation of the UC3845AD IC for a visual representation.

Key Features

• Current-Mode PWM Controller: Provides stable and reliable current-mode control for switch-mode power supplies.
• Wide Operating Voltage Range: Operates with supply voltages ranging from 8V to 35V, suitable for various power supply applications.
• Adjustable Frequency: Offers adjustable oscillator frequency for flexibility in power supply design.
• Protection Features: Includes shutdown pin (SD) and overcurrent protection for enhanced system reliability.
• High Efficiency: Optimized for high-efficiency power conversion with minimal power loss.

Note: For detailed technical specifications, please refer to the UC3845AD datasheet.

Application

• Switch-Mode Power Supplies: Ideal for use in designing efficient switch-mode power supplies for various electronic devices.
• DC-DC Converters: Suitable for DC-DC converter applications requiring precise voltage and current regulation.
• Battery Chargers: Used in battery charger circuits for efficient charging and power management.

Functionality

The UC3845AD integrates current-mode PWM control with adjustable frequency, providing precise regulation of output voltage and current in switch-mode power supplies.

Usage Guide

• Power Supply: Connect VCC (Pin 1) to the positive power supply and GND (Pin 4) to ground.
• Oscillator Components: Use external resistors and capacitors connected to RT/CT (Pin 6) to set the oscillator frequency.
• Feedback Loop: Connect FB (Pin 5) to the feedback network for voltage regulation.

Frequently Asked Questions

Q: What is the maximum supply voltage for the UC3845AD?
A: The UC3845AD can operate with a maximum supply voltage of 35V.

Q: Can the UC3845AD be synchronized with an external clock?
A: Yes, the UC3845AD includes a synchronization input (SYNC) for synchronization with an external clock signal.