UC2855AN

Basic Information Overview

• Category: Integrated Circuit (IC)
• Use: Voltage Mode PWM Controller
• Characteristics:
  • High-performance voltage mode controller
  • Designed for offline and DC-to-DC converter applications
  • Provides precise regulation of output voltage
  • Offers protection features for enhanced reliability
• Package: DIP-16 (Dual In-line Package with 16 pins)
• Essence: Regulates voltage in power supply circuits
• Packaging/Quantity: Available in tubes or reels, quantity varies based on supplier

Specifications

• Input Voltage Range: 10V to 30V
• Output Voltage Range: 0.8V to 15V
• Maximum Output Current: 1A
• Operating Temperature Range: -40°C to 85°C
• Frequency Range: 50kHz to 500kHz
• Duty Cycle Range: 0% to 100%
• Error Amplifier Gain Bandwidth: 2MHz

Detailed Pin Configuration

1. VCC: Power supply input
2. GND: Ground reference
3. COMP: Compensation pin for error amplifier
4. FB: Feedback pin for output voltage regulation
5. CS: Current sense input for current limiting
6. RT/CT: Timing components connection for frequency control
7. SYNC: Synchronization input for external clock
8. SS/TR: Soft-start and shutdown control pin
9. INV: Inverting input of the error amplifier
10. NC: No connection
11. OSC: Oscillator timing capacitor connection
12. CT: Timing capacitor connection for frequency control
13. RT: Timing resistor connection for frequency control
14. DRV: Gate driver output for driving external MOSFET
15. VREF: Reference voltage output
16. VCC: Power supply input

Functional Features

• Precise voltage regulation through feedback loop
• Adjustable frequency and duty cycle for flexible operation
• Current limiting to protect power supply components
• Soft-start function for gradual startup and reduced stress
• Synchronization capability with external clock source
• Error amplifier with high gain bandwidth for accurate control

Advantages

• High-performance controller for efficient power supply designs
• Wide input and output voltage range for versatile applications
• Comprehensive protection features enhance system reliability
• Flexible frequency and duty cycle control for optimized performance
• Compact DIP-16 package allows easy integration into circuits

Disadvantages

• Limited maximum output current of 1A may not be suitable for high-power applications
• Requires external MOSFET for driving power switches
• Not suitable for low-voltage applications below 0.8V

Working Principles

The UC2855AN is a voltage mode PWM controller that regulates the output voltage of power supply circuits. It operates by comparing the feedback voltage (FB) with a reference voltage (VREF) and adjusts the duty cycle of the output waveform accordingly. This feedback loop ensures precise regulation of the output voltage. The controller also includes an error amplifier, which amplifies the voltage difference between the feedback pin (FB) and the inverting input (INV). This amplified error signal is used to adjust the duty cycle and maintain the desired output voltage.

Detailed Application Field Plans

The UC2855AN is commonly used in various offline and DC-to-DC converter applications, including: - Switching power supplies - Battery chargers - LED drivers - Industrial control systems - Telecommunication equipment - Automotive electronics

Detailed and Complete Alternative Models

• UC2854AN: Similar voltage mode PWM controller with lower output current capability (500mA)
• UC3845AN: Voltage mode PWM controller with higher output current capability (2A)
• TL494CN: PWM controller with similar features and package, but different pin configuration

Note: The above alternative models are provided as examples and may not cover all available options. It is recommended to consult the manufacturer's datasheets for a comprehensive list of alternatives.

This entry provides an overview of the UC2855AN voltage mode PWM controller, including its basic information, specifications, pin configuration, functional features, advantages and disadvantages, working principles, application field plans, and alternative models.