Overview
The UC3825DW is a high-performance pulse-width modulation (PWM) controller IC designed by Texas Instruments. It is optimized for high-frequency switched-mode power supply applications and is compatible with both voltage and current mode topologies. This controller is particularly useful for applications requiring precise control over duty cycle and frequency, ensuring efficient and reliable power delivery.
The UC3825DW features a robust design with minimal propagation delays, high bandwidth error amplifiers, and fully latched logic to prevent multiple pulses at the output. It also includes protection mechanisms such as under-voltage lockout, current limiting, and soft start capabilities, making it suitable for a wide range of power supply and motor control applications.
Key Specifications
| Specification | Value |
|---|---|
| Package | SOIC (DW) - 16 pins |
| Operating Temperature Range | 0°C to 70°C |
| Operating Voltage Range | 8V to 35V |
| Frequency Range | Up to 500 kHz (practical operation up to 1 MHz) |
| Duty Cycle Range | 0% to 85% |
| Output Current (Peak) | 1.5A |
| Propagation Delay to Output | 50ns |
| Under-Voltage Lockout (UVLO) | 9.2V to 8.4V with hysteresis |
| Start-Up Current | 1.1mA |
Key Features
- Compatible with voltage or current mode topologies
- Practical operation switching frequencies up to 1 MHz
- 50ns propagation delay to output
- High current dual totem pole outputs (1.5A peak)
- Wide bandwidth error amplifier
- Fully latched logic with double pulse suppression
- Pulse-by-pulse current limiting
- Soft start / maximum duty cycle control
- Under-voltage lockout with hysteresis
- Low start-up current (1.1mA)
- Programmable frequency and duty cycle
- Shutdown function for easy system management
Applications
- Switch-mode power supplies: Regulating output voltage and current in various electronic devices.
- Motor control: Driving and controlling the speed of DC motors and brushless DC motors.
- Inverters: Converting DC power to AC power in applications such as solar inverters, UPS systems, and motor drives.
- Battery chargers: Regulating and controlling the charging process for various types of batteries.
- LED drivers: Driving and controlling the brightness of LEDs with precise dimming control.
Q & A
- What is the UC3825DW used for?
The UC3825DW is used in switch-mode power supplies, motor control systems, inverters, battery chargers, and LED drivers for precise control over duty cycle and frequency.
- What are the key features of the UC3825DW?
The UC3825DW features include compatibility with voltage or current mode topologies, high current dual totem pole outputs, wide bandwidth error amplifier, fully latched logic, pulse-by-pulse current limiting, soft start, and under-voltage lockout with hysteresis.
- What is the operating voltage range of the UC3825DW?
The operating voltage range of the UC3825DW is from 8V to 35V.
- What is the maximum operating frequency of the UC3825DW?
The UC3825DW can operate up to 500 kHz, with practical operation up to 1 MHz.
- What protection mechanisms does the UC3825DW have?
The UC3825DW includes protection mechanisms such as under-voltage lockout with hysteresis, current limiting, and soft start capabilities.
- How does the UC3825DW differ from the UC3845?
The UC3825DW and UC3845 differ in their operating frequency ranges and additional protection features. The UC3845 offers higher operating frequency and more advanced protection features.
- What is the package type of the UC3825DW?
The UC3825DW is available in a 16-pin SOIC (DW) package.
- What are the typical applications where the UC3825DW is used?
The UC3825DW is commonly used in power supplies, motor control systems, inverters, battery chargers, and LED drivers.
- What considerations should be taken into account when using the UC3825DW in power supply designs?
Designers should consider proper component selection, feedback loop design, and thermal management. Attention to current limiting and soft start features is also important for system protection.
- What is the start-up current of the UC3825DW?
The start-up current of the UC3825DW is 1.1mA.
- Is the UC3825DW compatible with other PWM controllers?
Yes, the UC3825DW is compatible with other PWM controllers from the same family, allowing for seamless integration and design flexibility.
