ST ISA082V1 User Manual

STEVAL-ISA082V1

4 A peak 800 kHz fixed-frequency PWM synchronous step-down

demonstration board with enable on/off based on the ST1S40IPHR

Data brief

Features

■ Input voltage V

■ Output voltage V

■ Maximum output current : 4 A

■ Switching frequency: 800 kHz

■ Short-circuit protected

■ RoHS compliant

: 4 V to 18 V

in

: 3.3 V

out

Description

The STEVAL-ISA082V1, based on the
ST1S40IPHR, is an internally compensated
800 kHz fixed-frequency PWM synchronous step­down converter demonstration board.

The ST1S40 operates from 4.0 V to 18.0 V input,
while it regulates an output voltage as low as

0.8 V and up to V

The ST1S40 integrates a 95 mΩ high-side switch
and a 69 mΩ synchronous rectifier allowing very
high efficiency with very low output voltage.

The peak current mode control with internal
compensation delivers a very compact solution
with a minimum component count.

(100% duty cycle).

IN

STEVAL-ISA082V1

The ST1S40 is protected through cycle-by-cycle
current limiting in case of overload and is also
protected by a current foldback function with
frequency reduction in case of short-circuit.

The device is available with an enable on/off
function.

September 2011 Doc ID 022276 Rev 1 1/4

For further information contact your local STMicroelectronics sales office.

www.st.com

4

Circuit schematic STEVAL-ISA082V1

1 Circuit schematic

Figure 1. Circuit schematic

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2/4 Doc ID 022276 Rev 1