STMICROELECTRONICS STEVAL

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 Vin : 4 V to 18 V
■
Output voltage Vout : 3.3 V
■
Maximum output current : 4 A
■
Switching frequency: 800 kHz
■
Short-circuit protected
■
RoHS compliant
Description
The STEVAL-ISA082V1, based on the
ST1S40IPHR, is an internally compensated
800 kHz fixed-frequency PWM synchronous stepdown converter demonstration board.
STEVAL-ISA082V1
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 VIN (100% duty cycle).
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.
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
For further information contact your local STMicroelectronics sales office.
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Circuit schematic
STEVAL-ISA082V1
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Circuit schematic
Figure 1.
Circuit schematic
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STEVAL-ISA082V1
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Revision history
Revision history
Table 1.
Document revision history
Date
Revision
27-Sep-2011
1
Changes
Initial release.
Doc ID 022276 Rev 1
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STEVAL-ISA082V1
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