SP6231EB
Evaluation Board Manual
Easy Evaluation for the SP6231 Linear
Regulator with Auxiliary Backup.
Evaluation Board provides complete,
ready to use solutions ideal for Digital
Still Camera (DSC) with USB port.
5.0 In, 3.3V Out, 500mA LDO.
Integrated Auxiliary Voltage Switch 0.2鈩?
Glitch Free Transition between Two
Supplies: Battery or USB downloading.
Current Limit and Thermal Shutdown
Protection.
Fast Transient Response.
Applications: DSC, PCMCIA/PCI cards,
NIC Cards, Dual Power Systems.
DESCRIPTION
The SP6231 Evaluation Board is designed to help the user evaluate the performance of
the SP6231 for use as a dual power source for applications like a DSC with USB port
power for downloading. The Evaluation Board operates from a 5V main supply which
can be from the on-board USB connector, providing a regulated 3.3V output at 500mA
or if that input is not present then from a 3.3V AUX switch input. The 3.3V AUX input is
available from an on-board option: Sipex鈥檚 SP6641B 2 Cell Battery Boost Converter to
3.3V auxiliary supply.
The SP6231 Evaluation Board can be used to provide glitch free transition between two
supplies. When the main power 5.0V input drops below 4.4V the auxiliary 3.3V is
switched to the output through the internal PFET. Thus, the SP6231 guarantees 3.3V
output 鈥済litch free鈥?operation.
SP6231REB SCHEMATIC
SP6231 500MA LDO WITH AUX SWITCH
VIN 5V
J2
USB CONNECTOR
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2
3
4
A MP# 7876 16
+5V
GND
J1
SHDN
1
2
3
4
SP6641B 2 CELL BOOST
U1 SP6641B
SHDN
V OUT
GND
5
V BATT
LX
3
2
1
6641 3.3V
VAUX
U2 SP6231
C3
2.2uF Cer.
1uF Cer.
C6
L2 SM Bead
VOUT 3.3V
1
V A UX
GND
GND
V out
V in
V sense
6
5
4
2
3
C2
100uF
80mohm
D1
C5
0.1uF
C4
10uF Cer.
VBATT
1.8V to 3.3V
C1
100uF
80mohm
L1
10uH
SCHOTTKY DIODE
Rev 09/24/02
SP6231 Evaluation Board Manual
Copyright Sipex Corporation
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