8-A buck converter optimized for power density and low EMI

The LM6x4xx family

of buck regulators are

regulators that provide either fixed or adjustable output voltage that can be set

from 1 V to 95% of expected input voltage. These regulators operate under a wide

input voltage range or 3 V to 36 V and have transient tolerance up to 42 V.

The family is designed for low EMI. The devices

incorporate pin-selectable spread spectrum and an adjustable SW node rise time. Dual

Random Spread Spectrum (DRSS) frequency hopping is set to ±5.5% (typical),

drastically reducing peak emissions through a combination of triangular and pseudo

random modulation. DRSS also 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 5 µA (typical). Electrical characteristics

are specified over a junction temperature range of –40°C to +150°C.