Overview
The UC3842N is a single-ended current-mode PWM controller produced by Texas Instruments. It is part of the UCx84x series of control integrated circuits, designed to implement off-line and DC-to-DC fixed-frequency current-mode control schemes with a minimum number of external components. This device is optimized for use in switching regulators and transformer-coupled DC-DC converters, offering a range of features that enhance performance and reliability.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | PDIP (P) | - |
| Pins | 8 | - |
| Operating Temperature Range | 0 to 70 | °C |
| Oscillator Frequency | 100 to 500 | kHz |
| Start-up Current | < 1 | mA |
| Undervoltage Lockout (UVLO) | 16V/10V with hysteresis | - |
| Output Drive Current | ±1 | A |
| Reference Voltage | 4.9 to 5.1 | V |
| Junction Temperature | 150 | °C |
| Storage Temperature | –65 to 150 | °C |
Key Features
- Optimized for off-line and DC-to-DC converters
- Low start-up current (< 1 mA)
- 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
- Switching regulators of any polarity
- Transformer-coupled DC-DC converters
- Off-line power supplies
- DC-DC applications
Q & A
- What is the operating temperature range of the UC3842N?
The UC3842N operates from 0°C to 70°C.
- What is the maximum oscillator frequency of the UC3842N?
The UC3842N can operate up to 500 kHz.
- What is the start-up current of the UC3842N?
The start-up current is less than 1 mA.
- What type of output stage does the UC3842N have?
The UC3842N has a high-current totem-pole output stage.
- What is the purpose of the undervoltage lockout (UVLO) in the UC3842N?
The UVLO ensures the device operates only when the input voltage is within a safe range, preventing damage due to low voltage conditions.
- What kind of compensation does the UC3842N offer?
The UC3842N offers automatic feedforward compensation.
- What is the reference voltage of the UC3842N?
The reference voltage is between 4.9 V and 5.1 V.
- Can the UC3842N be used in off-line power supplies?
- What is the maximum output drive current of the UC3842N?
The maximum output drive current is ±1 A.
- What type of packages are available for the UC3842N?
The UC3842N is available in PDIP (P) and other package options such as SOIC and CFP.
