Overview
The UC3842AD8TR is a current-mode PWM controller from Texas Instruments, part of the UCx84xA family. This device is optimized for off-line and DC-DC converters, offering several improved features over its predecessors. It is designed to control current-mode or switched-mode power supplies with a minimal number of external components. The UC3842AD8TR operates within a temperature range of 0°C to 70°C and is packaged in an 8-pin SOIC (D) package.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Operating Temperature Range | 0 to 70 | °C |
| Package Type | SOIC (D) | - |
| Number of Pins | 8 | - |
| Maximum Operating Voltage (VCC) | 30 | V |
| Start-Up Current | < 0.5 mA | mA |
| Oscillator Frequency | Up to 500 kHz | kHz |
| Output Current (Totem Pole) | Up to 1 A | A |
| Undervoltage Lockout (UVLO) Start Threshold | 14.5 to 17.5 V | V |
| Minimum Operation Voltage After Turn-On | 8.5 to 11.5 V | V |
| Maximum Duty Cycle | Up to 94% | % |
Key Features
- Optimized for off-line and DC-DC converters
- Low start-up current (< 0.5 mA)
- 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 500 kHz operation
- Error amplifier with low output resistance
Applications
The UC3842AD8TR is suitable for various power supply applications, including:
- Switching regulators of any polarity
- Transformer-coupled DC-DC converters
- Off-line flyback converters
- Isolated or non-isolated power supply designs
Q & A
- What is the operating temperature range of the UC3842AD8TR?
The operating temperature range is 0°C to 70°C.
- What is the package type and number of pins for the UC3842AD8TR?
The UC3842AD8TR is packaged in an 8-pin SOIC (D) package.
- What is the maximum operating voltage (VCC) for the UC3842AD8TR?
The maximum operating voltage is 30 V.
- What is the start-up current of the UC3842AD8TR?
The start-up current is less than 0.5 mA.
- What is the maximum oscillator frequency of the UC3842AD8TR?
The maximum oscillator frequency is up to 500 kHz.
- What is the output current capability of the totem pole stage in the UC3842AD8TR?
The totem pole stage can deliver up to 1 A of peak current.
- What are the undervoltage lockout (UVLO) start and minimum operation thresholds for the UC3842AD8TR?
The UVLO start threshold is between 14.5 to 17.5 V, and the minimum operation voltage after turn-on is between 8.5 to 11.5 V.
- What is the maximum duty cycle of the UC3842AD8TR?
The maximum duty cycle is up to 94%.
- What types of power supplies can the UC3842AD8TR be used in?
The UC3842AD8TR can be used in off-line and DC-DC converters, including switching regulators and transformer-coupled DC-DC converters.
- How does the UC3842AD8TR handle current limiting?
The UC3842AD8TR features pulse-by-pulse current limiting.
