描述 Description

The LM614xxT-Q1 buck converters are automotive-focused regulators providing adjustable output voltage which can be set from 1V to 95% of expected input voltage. These regulators operate under a wide input voltage range of 3V to 36V and have transient tolerance up to 42V.

The family is designed for low EMI. The device incorporates pin selectable spread spectrum, and an adjustable SW node rise time. Dual Random Spread Spectrum (DRSS) frequency hopping is set to ±4% (typical), drastically reducing peak emissions through a combination of triangular and pseudorandom modulation, and includes advanced techniques to reduce output voltage ripple caused by spread spectrum modulation.

An open-drain RESET output, with filtering and delayed release, gives a true indication of system status. In auto mode, the device automatically transitions between Fixed frequency Pulse Width Modulation (FPWM) and Pulse Frequency Modulation (PFM) modes of operation, allowing an unloaded current consumption of only 5μA (typical). Electrical characteristics are specified over a junction temperature range of –40°C to +150°C.

特性 Features

AEC-Q100 qualified for automotive applications:

Temperature grade 1: –40°C to +125°C, TA



Functional Safety-Capable

Documentation available to aid functional safety system design



Input voltage range from 3V to 36V

RESET output with filter and delayed release

Designed for low EMI:

CISPR 25 class 5 compliant EVM

Pin-configurable spread spectrum

Adjustable SW node rise time

Above and below AM band operation: pin configurable 400kHz and 2.2MHz fixed or adjustable from 200kHz – 2.2MHz

Low EMI symmetrical pinout

Light load mode is pin-configurable for constant frequency or pulse frequency modulation (PFM)



High-efficiency design

95% efficient for an 8A load

5μA input current while unloaded in auto mode

< 1μA shutdown current (typical)



Thermally enhanced package enabling top-side cooling

High power density

Built-in compensation, soft start, current limit, thermal shutdown, and UVLO

4.5mm × 3.5mm wettable flank QFN package