Description
The L4976 is a step down monolithic power switching regulator delivering 1A at a voltage between 3.3V and 50V (selected by a simple external divider). Realized in BCD mixed technology, the device uses an internal power DMOS transistor (with a typical Rds(ON) of 0.25Ω) to obtain very high efficency and high switching speed. A switching frequency up to 300KHz is achievable (the maximum power dissipation of the packages must be observed). A wide input voltage range between 8V to 55V and output voltages regulated from 3.3V to 40V cover the majority of today’s applications. Features of this new generations of DC-DC converter include pulse-by-pulse current limit, hiccup mode for short circuit protection, voltage feedforward regulation, protection against feedback loop disconnection and thermal shutdown. The device is available in plastic dual in line, MINIDIP 8 for standard assembly, and SO16W for SMD assembly.

Features
■ Up to 1A step down converter
■ Operating input voltage from 8v to 55v
■ Precise 5.1V reference voltage
■ Output voltage adjustable from 0.5V to 50V
■ Switching frequency adjustable up to 300kHz
■ Voltage feedforward
■ Zero load current operation
■ Internal current limiting (pulse-bypulse
■ and hiccup mode)
■ Protection against feedback disconnection
■ Thermal shutdown