CY8CKIT-046 PSoC® 4 L-Series Pioneer Kit Guide, Doc. #: 002-03344 Rev. *D
60
Appendix
Protection Circuits
The power supply rail has reverse-voltage, overvoltage, short circuit, and excess current protection
features, as shown in
.
Figure A-3. Power Supply Block Diagram with Protection Circuits
■
A PTC resettable fuse is connected to protect the USB Mini-B connectors from shorts and over
current.
■
ORing diodes prevent damage to components when the board is powered from different voltage
sources at the same time.
■
ESD protection is provided for the USB Mini-B connectors.
Current Measurement Jumper
To measure the PSoC 4200L power consumption, a header is populated in series with the power
supply to the PSoC 4200L. This header is used to measure current using an ammeter without the
need to de-solder any components from the board (marked 15 in
Figure A-4. Current Measurement Jumper Schematics
I/O Header
KitPr
o
g
US
B
PSoC 4200L
5V
Vin
3.3V
KitProg
KitProg 10-Pin
Prog. Header
PTC
ADJ LDO
ESD
Protection
PSoC 4200L 10-Pin
Prog. Header
Current measurement
header
5V
Power Selection
jumper
PSo
C
4200
L
US
B
VBUS
PTC
VBUS
ESD
Protection
Power Monitoring
NO LOAD
J14 Jumper Settings
1 & 3 -> 10 Ohm Shunt
2 & 4 -> 1 Ohm Shunt
3 & 4 -> Short out shunts, VDD to P4L_VDD
NO LOAD
NO LOAD
NO LOAD
NO LOAD
NO LOAD
No Shunt -> No power to U5, PSoC 4200L
P4L_VDD
VDD
VTARG
P
5LP
3_2
P
5LP
2_0
P
5LP
2_1
P
5LP
3_3
TP15
RED
R83
10 Ohm
R84
ZERO
R80
ZERO
R85
ZERO
R79
1 Ohm
R82
ZERO
J14
CON4
1
2
3
4