Overview
The UC3843ADG4 is a current-mode PWM (Pulse Width Modulation) controller IC produced by Texas Instruments. It is part of the UCx84xA family, which is designed to control current-mode or switched-mode power supplies. This IC is optimized for off-line and DC-DC converters, offering several improved features over its predecessors. It is known for its low start-up current, trimmed oscillator discharge current, and enhanced load response characteristics, making it a versatile choice for various power supply applications.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Operating Temperature Range | 0 to 70 | °C |
| Start-Up Current | < 0.5 | mA |
| Oscillator Discharge Current | 8.3 | mA |
| Output Stage Sink Current (UVLO) | 10 | mA at VCC > 5V, VOUT < 1.2V |
| Maximum Duty Cycle | Up to 100% | |
| Oscillator Frequency Range | 100 to 500 | kHz |
| Reference Voltage | 4.9 to 5.1 | V |
| Output Drive Current | ±1 | A |
| Package Options | SOIC (8, 14), PDIP (8), CFP (8) |
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
- Error amplifier with low output resistance
Applications
- Switching regulators of any polarity
- Transformer-coupled DC-DC converters
- SMPS (Switch Mode Power Supplies)
- RPS (Regulated Power Supplies)
- DC-DC converters
- Line voltage regulators
Q & A
- What is the UC3843ADG4 used for?
The UC3843ADG4 is used to control current-mode or switched-mode power supplies, particularly in off-line and DC-DC converter applications.
- What is the start-up current of the UC3843ADG4?
The start-up current of the UC3843ADG4 is less than 0.5mA.
- What is the oscillator discharge current of the UC3843ADG4?
The oscillator discharge current is trimmed to 8.3mA.
- What is the maximum operating frequency of the UC3843ADG4?
The maximum operating frequency is up to 500kHz.
- What are the package options available for the UC3843ADG4?
The UC3843ADG4 is available in SOIC (8, 14), PDIP (8), and CFP (8) packages.
- What is the operating temperature range of the UC3843ADG4?
The operating temperature range is from 0°C to 70°C.
- Does the UC3843ADG4 have undervoltage lockout (UVLO) protection?
Yes, the UC3843ADG4 features undervoltage lockout with hysteresis.
- Can the UC3843ADG4 be used in DC-DC converter applications?
Yes, the UC3843ADG4 is suitable for DC-DC converter applications.
- What is the reference voltage of the UC3843ADG4?
The reference voltage is between 4.9V and 5.1V.
- Does the UC3843ADG4 have pulse-by-pulse current limiting?
Yes, the UC3843ADG4 features pulse-by-pulse current limiting.
