ST ISA079V1 User Manual

STEVAL-ISA079V1

High efficiency monolithic synchronous step-down regulator based

on the L6928D

Data brief − preliminary data

Features

■

2 V to 5.5 V battery input range

■

High efficiency: up to 95%

■

Extremely low quiescent current

■

1 µA max. shutdown supply current

■

800 mA max. output current

■

Adjustable output voltage from 0.6 V

■

Low dropout operation: up to 100% duty cycle

■

± 1% output voltage accuracy

■

1.4 MHz switching frequency externally
synchronizable from 1 MHz to 2 MHz

■

Short-circuit protection

■

RoHS compliant

Description

The STEVAL-ISA079V1 demonstration board is
based on the DC-DC monolithic regulator
L6928D, specifically designed to provide
extremely high efficiency.

The L6928D supply voltage can be as low as 2 V,
allowing it to be used in single Li-Ion cell supplied
applications.

Output voltage can be selected by an external
divider down to 0.6 V.

Duty cycle can saturate to 100%, allowing low
dropout operation.

The previous part number for this demonstration
board was EVAL6928D.

March 2012 Doc ID 022890 Rev 1 1/4

This is preliminar y information on a new product now in development or undergoing evaluation. Details are subject to
change without notice. For further information contact your local STMicroelectronics sales office.

www.st.com

4

Circuit schematic STEVAL-ISA079V1

AM12058v1

VIN= 2 to 5.5V

V

IN

= 1.8V

C1

10µF

6.3V
R2

100kΩ

R4

100kΩ

R3

200kΩ

L1 4.7µH

C2

10µF

6.3V

C3

220pF

R1

10kΩ

LX

PGOOD

VFB

GNDCOMP

V

CC

RUN

SYNC

5

8

3

7

1

6

24

L6928D

1 Circuit schematic

Figure 1. Circuit schematic

2/4 Doc ID 022890 Rev 1