Overview
The LM5025MTCX/NOPB, produced by Texas Instruments, is an active clamp voltage mode PWM controller designed for high-efficiency power conversion applications. This controller utilizes the active clamp and reset technique to achieve higher efficiencies and greater power densities compared to conventional methods. It supports both P-channel and N-channel clamp switches and features two control outputs: the main power switch control (OUT_A) and the active clamp switch control (OUT_B). The LM5025 includes a high-voltage start-up regulator, operating over a wide input range of 13 V to 90 V, and is optimized for high-speed operation with oscillator frequencies up to 1 MHz and propagation delays less than 100 ns.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VIN Voltage | 13 | 90 | V | |
| Operating Junction Temperature | -40 | 125 | °C | |
| Oscillator Frequency | 175 | 200 | 225 | kHz |
| Max Duty Cycle | 80 | % | ||
| Thermal Shutdown Threshold | 165 | °C | ||
| Thermal Shutdown Hysteresis | 25 | °C | ||
| Package Type | TSSOP-16, WSON-16 |
Key Features
- Internal Start-Up Bias Regulator: Allows the input pin (VIN) to be connected directly to the line voltage.
- Programmable Line Undervoltage Lockout (UVLO): With adjustable hysteresis.
- Voltage Mode Control with Feed-Forward: Enhances stability and performance.
- Adjustable Dual-Mode Overcurrent Protection: Includes cycle-by-cycle and hiccup current limiting modes.
- Programmable Soft-Start: Reduces inrush current during startup.
- Oscillator UP and DOWN Sync Capability: Allows synchronization with external clocks.
- Precision 5-V Reference: Provides a stable voltage reference.
- Thermal Shutdown: Protects the device from overheating.
- Compound Gate Drivers: Parallel both MOS and bipolar devices for superior gate drive characteristics.
- Volt × Second Clamp: Limits the maximum ON time of the main switch.
Applications
- Server Power Supplies: High-efficiency DC-to-DC power supplies.
- 48-V Telecom Power Supplies: Reliable and efficient power solutions for telecom systems.
- 42-V Automotive Applications: Suitable for automotive power systems requiring high reliability and efficiency.
- High-Efficiency DC-to-DC Power Supplies: General use in high-efficiency power conversion applications.
Q & A
- What is the input voltage range of the LM5025?
The input voltage range of the LM5025 is from 13 V to 90 V.
- What types of overcurrent protection does the LM5025 offer?
The LM5025 offers both cycle-by-cycle and hiccup current limiting modes.
- What is the maximum oscillator frequency of the LM5025?
The maximum oscillator frequency of the LM5025 is up to 1 MHz.
- What are the package options for the LM5025?
The LM5025 is available in TSSOP-16 and WSON-16 packages.
- What is the thermal shutdown threshold of the LM5025?
The thermal shutdown threshold of the LM5025 is 165°C with a hysteresis of 25°C.
- Can the LM5025 be synchronized with an external clock?
Yes, the LM5025 can be synchronized with an external clock that is either higher or lower than the internal oscillator frequency.
- What is the purpose of the volt × second clamp in the LM5025?
The volt × second clamp limits the maximum ON time of the main switch and varies inversely with the line voltage.
- How does the LM5025 handle soft-start?
The LM5025 features a programmable soft-start to reduce inrush current during startup.
- What are the key benefits of using the active clamp technique in the LM5025?
The active clamp technique in the LM5025 allows for higher efficiencies and greater power densities compared to conventional methods.
- What is the maximum duty cycle of the LM5025?
The maximum duty cycle of the LM5025 is 80%.
