1A STEP DOWN SWITCHING REGULATOR
UP TO 1A STEP DOWN CONVERTER
OPERATING INPUT VOLTAGE FROM 8V TO
PRECISE 5.1V REFERENCE VOLTAGE
OUTPUT VOLTAGE ADJUSTABLE FROM
3.3V TO 50V
SWITCHING FREQUENCY ADJUSTABLE UP
ZERO LOAD CURRENT OPERATION
INTERNAL CURRENT LIMITING (PULSE-BY-
PULSE AND HICCUP MODE)
PROTECTION AGAINST FEEDBACK DIS-
The L4976 is a step down monolithic power
switching regulator delivering 1A at a voltage be-
tween 3.3V and 50V (selected by a simple exter-
nal divider). Realized in BCD mixed technology,
the device uses an internal power D-MOS transis-
tor (with a typical Rdson of 0.25Ω) to obtain very
high efficency and high switching speed.
A switching frequency up to 250KHz is achiev-
able (the maximum power dissipation of the pack-
TYPICAL APPLICATION CIRCUIT
ORDERING NUMBERS: L4976 (Minidip)
ages 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 con-
verter include pulse-by-pulse current limit, hiccup
mode for short circuit protection, voltage feedfor-
ward 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.
Vi=8V to 55V