NCP345EVB ON Semiconductor, NCP345EVB Datasheet - Page 2

• Manufacturer Part Number: NCP345EVB
• Description: EVAL BOARD FOR NCP345
• Manufacturer: ON Semiconductor

Specifications of NCP345EVB

• Design Resources: NCP345 Demo Board BOM NCP345EVB Gerber Files NCP345/6 EVB Schematic
• Main Purpose: Overvoltage Protection
• Embedded: No
• Utilized Ic / Part: NCP345
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Secondary Attributes: -
• Primary Attributes: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: NCP345
• Other names: NCP345EVBOS

choose to implement this solution. The drain−source
breakdown voltage (V
Table 1. Small, Surface−Mount FETs
applications that may be connected directly to the input
measures to prevent users from unsuspectingly damaging
their products. Reversed and overvoltage inputs are
common problems which have been addressed here. This
NTHS4111P
NTGS4111P
NTJS4151P
NTHS5443
NTHS5441
NTHS4101P
NTHD4102P
NTJS3151P
Table 2 shows a variety of MOSFETs that one could
This same technique works in a variety of other
Designers of portable products must include protective
Part Number
V
+
−
in
Q1
DSmax
Figure 2. Reverse Protection Circuit with Li−Ion Battery Charger
V
4.7 mF
) and the gate−source
DSmax
C
30
30
20
20
20
20
20
12
in
(V)
R
80 k
ISEL
CFLG
FAULT
V
ISEL TIMER
CC
http://onsemi.com
V
15 nF
C
GSmax
T
"20
"20
"12
"12
"12
"12
"8
"8
VSNS
2
V2P8
GND
BAT
(V)
EN
breakdown voltage (V
magnitude of the expected overvoltage and reverse voltage
events.
adapter port. A common circuit which is often connected
directly to the adapter port is a Li−Ion battery charger.
proposed addition of the reverse polarity adds reverse
protection to a robust overvoltage protection solution with
a minimal addition of series conduction loss and without the
voltage drop of a Schottky diode.
0.1 mF
C
2p8
Microprocessor
4.7 mF
C
R
52 @ 4.5 V
68 @ 4.5 V
70 @ 2.5 V
95 @ 2.5 V
70 @ 2.5 V
30 @ 2.5 V
85 @ 2.5 V
67 @ 2.5 V
out
DS(on)
GSmax
(mW)
) should be greater than the
ChipFETt
ChipFETt
ChipFETt
ChipFETt
ChipFETt
Package
TSOP−6
SC88
SC88