Overview
The LM3481MM/NOPB is a high-efficiency controller designed by Texas Instruments for use in boost, SEPIC, and flyback DC-DC converters. This versatile device is a low-side N-FET high-performance controller, optimized for applications requiring high switching frequencies to minimize overall solution size. It features a current mode control architecture, which provides superior bandwidth and transient response along with cycle-by-cycle current limiting. The LM3481MM/NOPB includes built-in protection features such as thermal shutdown, short-circuit protection, and overvoltage protection, ensuring reliable operation under various conditions.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage | 2.97 | 48 | V | |
| Switching Frequency Range | 100 kHz | 1 MHz | ||
| Peak Current Capability | 1 A | |||
| Internal Reference Voltage | 1.275 | V | ||
| Shutdown Current | 10 µA | |||
| Junction Temperature Range | -40 | 125 | °C | |
| Package Type | 10-Lead VSSOP |
Key Features
- Internal push-pull driver with 1A peak current capability
- Current limit and thermal shutdown
- Frequency compensation optimized with a capacitor and a resistor
- Internal soft start to limit inrush current at start-up
- Current mode operation with cycle-by-cycle current limiting
- Adjustable undervoltage lockout with hysteresis
- Pulse skipping at light loads for improved efficiency
- Overvoltage protection (OVP) sensed at the feedback pin
- Integrated current slope compensation
Applications
- Boost converters for audio amplifiers in portable speakers
- Wide input boost, SEPIC, and flyback power modules
- Isolated supply (flyback) applications
- Battery-powered boost, SEPIC, and flyback converters
Q & A
- What is the supply voltage range of the LM3481MM/NOPB?
The supply voltage range is from 2.97V to 48V.
- What is the switching frequency range of the LM3481MM/NOPB?
The switching frequency can be adjusted between 100 kHz and 1 MHz.
- What is the peak current capability of the internal push-pull driver?
The peak current capability is 1A.
- Does the LM3481MM/NOPB have built-in protection features?
Yes, it includes thermal shutdown, short-circuit protection, and overvoltage protection.
- How does the LM3481MM/NOPB handle light load conditions?
It uses pulse skipping to improve efficiency at light loads.
- What is the package type of the LM3481MM/NOPB?
The package type is a 10-Lead VSSOP.
- Can the switching frequency be synchronized to an external clock?
Yes, the switching frequency can be synchronized to an external clock.
- Does the LM3481MM/NOPB support adjustable undervoltage lockout?
Yes, it supports adjustable undervoltage lockout with hysteresis.
- What is the junction temperature range of the LM3481MM/NOPB?
The junction temperature range is from -40°C to 125°C.
- How does the LM3481MM/NOPB manage overvoltage protection?
Overvoltage protection is sensed at the feedback pin and triggers the drive pin to go low, forcing the power MOSFET off.
