Overview
The UC3843D8TR is a single-ended current-mode PWM (Pulse Width Modulation) controller produced by Texas Instruments. It is part of the UCx84x series, which is designed to implement off-line and DC-to-DC fixed-frequency current-mode control schemes with a minimal number of external components. This IC features an undervoltage lockout (UVLO) with a start-up current of less than 1mA and a precision reference trimmed for accuracy at the error amplifier input. The UC3843D8TR is optimized for high-frequency operation up to 500kHz and is suitable for driving N-channel MOSFETs.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | SOIC (D) | - |
| Pins | 8 | - |
| Operating Temperature Range | 0°C to 70°C | °C |
| Supply Voltage | Up to 30 | V |
| Output Current | ±1 | A |
| Oscillation Frequency | 47 to 57 kHz (typical) | kHz |
| Maximum Duty Cycle | 100% | % |
| UVLO Thresholds | Start: 7.8 to 9.0 V, Stop: 7.0 to 8.2 V | V |
| Start-Up Current | < 1 mA | mA |
Key Features
- Optimized for off-line and DC-to-DC converters
- Low start-up current (< 1mA)
- Automatic feedforward compensation
- Pulse-by-pulse current limiting
- Enhanced load-response characteristics
- Undervoltage lockout with hysteresis
- Double-pulse suppression
- High-current totem-pole output for driving N-channel MOSFETs
- Internally trimmed bandgap reference
- Up to 500kHz operation
- Error amplifier with low output resistance
Applications
The UC3843D8TR is specifically designed for use in off-line and DC-to-DC converter applications. It is suitable for a variety of power supply designs, including:
- Off-line power supplies
- DC-to-DC converters
- Switch-mode power supplies
- High-frequency power conversion systems
Q & A
- What is the operating temperature range of the UC3843D8TR?
The operating temperature range is from 0°C to 70°C.
- What is the maximum duty cycle of the UC3843D8TR?
The maximum duty cycle is up to 100%.
- What are the UVLO thresholds for the UC3843D8TR?
The start threshold is between 7.8 to 9.0 V, and the stop threshold is between 7.0 to 8.2 V.
- What is the typical oscillation frequency of the UC3843D8TR?
The typical oscillation frequency is between 47 to 57 kHz.
- What is the start-up current of the UC3843D8TR?
The start-up current is less than 1 mA.
- What type of output stage does the UC3843D8TR have?
The UC3843D8TR has a high-current totem-pole output stage designed for driving N-channel MOSFETs.
- What is the maximum supply voltage for the UC3843D8TR?
The maximum supply voltage is up to 30 V.
- What are some key features of the UC3843D8TR?
Key features include low start-up current, automatic feedforward compensation, pulse-by-pulse current limiting, and an internally trimmed bandgap reference.
- What types of applications is the UC3843D8TR suitable for?
The UC3843D8TR is suitable for off-line and DC-to-DC converter applications, including switch-mode power supplies and high-frequency power conversion systems.
- What package options are available for the UC3843D8TR?
The UC3843D8TR is available in an 8-pin SOIC (D) package.
