Overview
The UC2845AD8TR is a current-mode PWM (Pulse Width Modulation) controller produced by Texas Instruments. It is part of the UCx84xA family, which is designed to be a pin-for-pin compatible improvement over the UCx84x family. This controller is optimized for use in off-line and DC-DC converters, offering several enhanced features that improve performance and reliability in power supply applications.
Key Specifications
| Parameter | Value |
|---|---|
| Package | SOIC (D) - 8 pins |
| Operating Temperature Range | 40°C to 85°C |
| Input Voltage Range | 7.6V to 30V |
| Output Current | Up to 1A |
| Switching Frequency | Up to 500kHz |
| Undervoltage Lockout (UVLO) | 8.4V/7.6V with hysteresis |
| Duty Cycle | Up to 50% |
| Start-Up Current | < 0.5mA |
| Oscillator Discharge Current | Trimmed to 8.3mA |
Key Features
- Optimized for off-line and DC-DC converters
- Low start-up current (< 0.5mA)
- Trimmed oscillator discharge current
- Automatic feedforward compensation
- Pulse-by-pulse current limiting
- Enhanced load response characteristics
- Undervoltage lockout with hysteresis
- Double pulse suppression
- High-current totem pole output
- Internally-trimmed bandgap reference
- Up to 500kHz operation
Applications
The UC2845AD8TR is suitable for a variety of power supply applications, including:
- Off-line power supplies
- DC-DC converters (e.g., buck, boost, flyback, forward regulators)
- Isolation-capable output configurations
- Step-up, step-down, and step-up/step-down converters
Q & A
- What is the operating temperature range of the UC2845AD8TR?
The operating temperature range is from 40°C to 85°C.
- What is the maximum switching frequency of the UC2845AD8TR?
The maximum switching frequency is up to 500kHz.
- What is the undervoltage lockout (UVLO) threshold for the UC2845AD8TR?
The UVLO threshold is 8.4V/7.6V with hysteresis.
- What is the start-up current of the UC2845AD8TR?
The start-up current is less than 0.5mA.
- What types of power supplies is the UC2845AD8TR optimized for?
The UC2845AD8TR is optimized for off-line and DC-DC converters.
- Does the UC2845AD8TR support pulse-by-pulse current limiting?
- What is the package type and pin count of the UC2845AD8TR?
The package type is SOIC (D) with 8 pins.
- Is the UC2845AD8TR RoHS compliant?
- What are some of the enhanced features of the UC2845AD8TR compared to its predecessors?
Enhanced features include low start-up current, trimmed oscillator discharge current, automatic feedforward compensation, and enhanced load response characteristics.
- Can the UC2845AD8TR be used in isolation-capable output configurations?
