Overview
The LM3481QMMX/NOPB, produced by Texas Instruments, is a versatile and high-performance controller designed for use in boost, SEPIC, and flyback DC-DC converters. This device is part of the LM3481 family and is specifically packaged in a 10-lead VSSOP package. It is optimized for applications requiring a low-side N-FET as the primary switch. The LM3481QMMX/NOPB features a current mode control architecture, which provides superior bandwidth and transient response along with cycle-by-cycle current limiting. It is suitable for a wide range of applications, including automotive systems, due to its AEC-Q100 qualification.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage Range | 2.97 | - | 48 | V |
| Switching Frequency Range | 100 kHz | - | 1 MHz | - |
| Internal Reference Voltage | 1.256 | 1.275 | 1.294 | V |
| Peak Driver Current | - | 1 A | - | - |
| Shutdown Current | - | 10 µA | - | - |
| Operating Temperature Range | -40°C | - | 125°C | - |
Key Features
- Internal push-pull driver with 1A peak current capability
- Current limit and thermal shutdown protection
- 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
- Integrated current slope compensation
- Overvoltage protection (OVP) for the output voltage
- Power-saving shutdown mode reducing total supply current to 5 µA
Applications
- Boost converters for audio amplifiers in portable speakers
- Wide input boost, SEPIC, and flyback power modules
- Isolated supply (flyback) converters
- Battery-powered boost, SEPIC, and flyback converters
- Automotive applications such as traction inverters, on-board chargers, ADAS, driver monitoring, digital cockpit, and head units
Q & A
- What is the supply voltage range of the LM3481QMMX/NOPB?
The supply voltage range is from 2.97V to 48V.
- What is the switching frequency range of the LM3481QMMX/NOPB?
The switching frequency can be adjusted between 100 kHz and 1 MHz.
- What is the peak driver current capability of the LM3481QMMX/NOPB?
The peak driver current capability is 1 A.
- Does the LM3481QMMX/NOPB have built-in protection features?
- How does the LM3481QMMX/NOPB handle light load conditions?
It uses pulse skipping at light loads to improve efficiency.
- What is the operating temperature range of the LM3481QMMX/NOPB?
The operating temperature range is from -40°C to 125°C.
- Is the LM3481QMMX/NOPB suitable for automotive applications?
- How does the internal soft start feature work?
The internal soft start limits the inrush current at start-up.
- Can the switching frequency be synchronized to an external clock?
- What is the shutdown current of the LM3481QMMX/NOPB?
The shutdown current is 10 µA.
