Features
•AECQ100 qualification
• 2 A DC output current
• 4 V to 38 V operating input voltage
• Low consumption mode or low noise mode
• Programmable ISKIP current
• 30 μA IQ at light load (LCM VIN = 12 V and VOUT = 3.3 V)
• 8 μA IQ-SHTDWN
• Adjustable fSW (250 kHz - 2 MHz)
• Output voltage adjustable from 0.85 V to VIN
• Embedded output voltage supervisor
• Synchronization (in all fSW range)
• Adjustable soft-start time
• Internal current limiting
• Overvoltage protection
• Peak current mode architecture
• RDS(on)HS = 180 mΩ; RDS(on)LS = 150 mΩ
• Thermal shutdown
• RoHS and WEEE compliant
Description
The STEVAL-ISA205V1 product evaluation board is based on the synchronous step-
down switching regulator A6986H that can deliver up to 2 A and withstand cold
cranking across 100% duty cycle, which, along with its wide input operating voltage
range, render the A6986H the ideal choice for battery powered automotive systems.
Synchronous rectification helps to achieve higher efficiency at full load as well as
application compactness, while high-frequency switching (programmable up to 2
MHz) helps to cut power passive costs and size, while staying outside of the AM
band.
The device can operate in a Low Consumption Mode (LCM) with a quiescent current
down to 30 µA at VIN = 12 V and VOUT = 3.3 V, hence assuring high efficiency at light
loads, as required in typical car body applications that are active during car parking.
A Low Noise Mode (LNM) is also available to meet the requirements of infotainment
applications of forced PWM mode in all loading conditions.
The default configuration of the board is output voltage set to 3.3 V configured in
LCM, 500 kHz switching frequency, ISKIP current set to high level and the switchover
feature disabled. All of these settings can be easily changed by the user to evaluate
different application scenarios.
Product summary
38 V, 2 A synchronous
step-down switching
regulator evaluation board
based on A6986H
STEVAL-
ISA205V1
38 V, 2 A synchronous
step-down switching
regulator with 30 µA
quiescent current
A6986H
38 V, 2 A synchronous step-down switching regulator evaluation board based on
the A6986H
STEVAL-ISA205V1
Data brief
DB3889 - Rev 1 - April 2019
For further information contact your local STMicroelectronics sales office.
www.st.com
1Schematic diagram
Figure 1. STEVAL-ISA205V1 board schematic
+
C13A NM
TP8
VIN_EMI
J5
+
C13 NM
J4
L3
MPZ2012S221A
size 1206
J2
C14 4.7uF
L2 4.7uH
size 1206
PGND
C2 1uF 50V
R1 0
C1 10uF 50V
C4 2.2p
J3
R6 1M
power GND
size 1206
10V
R9 82k
VIN_FLT
R5 NM
TP4 VOUT
C10 10uF 50V
TP1
SS/INH
size 0805
size 1206
J1 C6
10nF
R4
0
L1A NM
VIN_FLT
C16 4.7uF
R3 NM
R10 NM
L1 10uH
TP6
GND
TP2 RST
size 1206
size XAL5030 Coilcraft
TP7 GND
PGND
signal GND
R2
NM
C11
NM
C15 4.7uF
R8 75k
TP5
VIN
C9 10uF 50V
C8 330p
C7 NM
R7 240k
size 1206
C5
68nF
U1 A6986H
RST 1
VCC
2
SS/INH
3
SYNCH
4
FSW
5
MLF
6
COMP 7
DELAY
8
FB 9
SGND
10
PGND
11
PGND
12
LX 13
LX 14
VIN
15 VBIAS 16
EP
17
C3
470nF
R11 10
TP3
SYNCH
DB3889 - Rev 1 page 2/4
STEVAL-ISA205V1
Revision history
Table 1. Document revision history
Date Version Changes
02-Apr-2019 1 Initial release.
STEVAL-ISA205V1
DB3889 - Rev 1 page 3/4
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© 2019 STMicroelectronics – All rights reserved
STEVAL-ISA205V1
DB3889 - Rev 1 page 4/4
