Overview
The LM51571QRTERQ1 is a wide input range, non-synchronous boost converter manufactured by Texas Instruments. It is part of the AEC-Q100 qualified series, making it suitable for automotive applications with a temperature range of –40°C to +125°C. This device integrates a 50-V, 4.33-A power switch and can operate in boost, SEPIC, and flyback topologies. It can start up from a single-cell battery with a minimum of 2.9 V and can operate with input supply voltages as low as 1.5 V if the BIAS pin is greater than 2.9 V. The device features a small solution size, low cost, and high efficiency with low-power dissipation.
Key Specifications
| Parameter | Minimum | Typical | Maximum | Unit |
|---|---|---|---|---|
| Input Voltage Range | 2.9 | - | 45 | V |
| Maximum Output Voltage | - | - | 48 (50 abs max) | V |
| Switch Current Limit | 4.33 | - | 5.67 | A |
| Switching Frequency | 100 kHz | - | 2.2 MHz | - |
| Shutdown Current (IQ) | - | - | 2.6 µA | - |
| Operating Current (IQ) | - | - | 700 µA | - |
| Package Type | - | - | 16-pin QFN (3 mm × 3 mm) | - |
| Internal MOSFET On-Resistance (RDSON) | 45 | - | 90 | mΩ |
| Thermal Shutdown Threshold | - | - | 175°C | - |
Key Features
- Wide input range: 2.9 V to 45 V, with minimum boost supply voltage of 1.5 V when BIAS ≥ 2.9 V.
- Integrated 50-V, 4.33-A power switch.
- Dynamically programmable switching frequency from 100 kHz to 2.2 MHz.
- Selectable dual random spread spectrum for EMI mitigation.
- Low shutdown current (IQ ≤ 2.6 µA) and low operating current (IQ ≤ 700 µA).
- Integrated error amplifier allows primary-side regulation without optocoupler (flyback).
- Accurate current limit and pulse-skipping operation for improved efficiency at light loads.
- Built-in protection features: overvoltage protection, line UVLO, thermal shutdown, and selectable hiccup mode overload protection.
- Programmable soft start, precision reference, and power-good indicator.
- External clock synchronization.
- Small solution size and low cost.
Applications
- Battery-powered wide input boost, SEPIC, and flyback converters.
- Automotive voltage stabilizer in SEPIC topology.
- Automotive start-stop applications.
- Automotive emergency call and backup battery booster applications.
- High voltage LiDAR power supply.
- Automotive LED bias supply.
- Multiple-output flyback without optocoupler.
- Holdup capacitor charger.
- Audio amplifier power supply.
- Piezo driver/motor driver bias supply.
Q & A
- What is the input voltage range of the LM51571QRTERQ1?
The input voltage range is from 2.9 V to 45 V. - What is the maximum output voltage of the LM51571QRTERQ1?
The maximum output voltage is 48 V (50 V absolute maximum). - What is the current limit of the integrated power switch?
The current limit is 4.33 A. - What are the switching frequency options for the LM51571QRTERQ1?
The switching frequency can be dynamically programmed from 100 kHz to 2.2 MHz. - What is the shutdown current (IQ) of the device?
The shutdown current (IQ) is less than or equal to 2.6 µA. - What package type is the LM51571QRTERQ1 available in?
The device is available in a 16-pin QFN package (3 mm × 3 mm). - Does the LM51571QRTERQ1 have built-in protection features?
Yes, it includes overvoltage protection, line UVLO, thermal shutdown, and selectable hiccup mode overload protection. - Can the LM51571QRTERQ1 be used in various topologies?
Yes, it can be used in boost, SEPIC, and flyback topologies. - How does the device mitigate EMI?
The device provides a selectable dual random spread spectrum to reduce EMI over a wide frequency range. - Is the LM51571QRTERQ1 suitable for automotive applications?
Yes, it is AEC-Q100 qualified for automotive applications.
