February 2016
DocID029028 Rev 1
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STEVAL-ISA160V1
3 A / 2.3 MHz step-down synchronous switching regulator based
on the AST1S31 HF in a DFN 3x3 package
Data brief
Features
AECQ100 qualification
3 A DC output current
2.8 V to 4 V input voltage
Output voltage adjustable from 0.8 V
2.3 MHz switching frequency
Internal soft-start and enable
Integrated 70 mΩ and 55 mΩ power
MOSFETs
All ceramic capacitor
Power good (POR)
Cycle by cycle current limiting
Current fold back short circuit protection
VFDFPN 3x3 - 8L package
RoHS compliant
Description
The STEVAL-ISA160V1 evaluation board is
based on the AST1S31HF internally
compensated 2.3 MHz fixed-frequency PWM
synchronous step-down regulator.
The device operates on a 2.8 V to 4.0 V input
voltage and provides a regulated output voltage
from as low as 0.8 V up to Vin.
The peak current mode control with internal
compensation delivers a very compact solution
with a minimum component count.
All the components on the evaluation board are
automotive grade.
Schematic diagram
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DocID029028 Rev 1
1 Schematic diagram
Figure 1: STEVAL-ISA160V1 circuit schematic
VIN
VOUT
L1
0.91uH
AST1S31HFU1
FB
3
AGND
4VIN_SW 6
VIN_A
1
EN
2SW 7
PGND 8
ePAD
9
PGOOD 5
R3
10K
C1
47uF C2
22uF
R1
100K
R2
200K
C3
1uF
GSPG2202161045SG
STEVAL-ISA160V1
DocID029028 Rev 1
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2 Revision history
Table 1: Document revision history
Date
Version
Changes
25-Feb-2016
1
Initial release.
STEVAL-ISA160V1
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DocID029028 Rev 1
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