Power Supply Selection - Semtech SX8724SEVK User Manual

ADVANCED COMMUNICATIONS & SENSING
8.2

Power Supply Selection

Available supply voltages vs. selected power source is described below.
IMPORTANT NOTICE
- DO NEVER CONNECT VEXT JUMPER IF EXTERNAL VOLTAGE IS HIGHER THAN 5.5VDC.
- CONNECT ONLY ONE JUMPER ON THIS SELECTOR
INTERFACES
USB
J6
1
VBUS
2
D-
3
D+
4
SHL D
5
GND
H2959CT-ND
VEXT
J8
GND
2
1
GND
The picture below shows the selector. User should place the jumper on the desired SX8724S supply voltage
value.
Power jumper
External voltage
5V from USB
Regulated 3.3V
Board voltage
ACS - Revision 1.0
© Semtech Corp.
W4
Ferrite
PGC/D-
F1
PGD/D+
C1 C2 C3
F2
27pF 27pF 10uF
GND GND GND
Figure 7. Power Supply Schematic
Enter here with an
Power LED
external power supply
Figure 8. SX8724SEVK Power Supply Selector
May 2011
Evaluation Kit for SX8724S Data Acquisition System
MCP1802
U3
1
VI N VOUT
3
SHDN
C4 C5
C6
1uF 100nF
NC
GND
GND GND GND
Page 13
SX8724SEVK
BOARD VOLTAGE SELECTOR
VBUS W2
VLDO W3 VBOARD
5
VEXT W1
C7 C8
1uF 100nF
GND GND
USER GUIDE
R3
470R
ON
Re d
GND
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