S-8425AAAFT-TB-X Datasheet, PDF (29/45 Pages) Seiko Instruments Inc – BATTERY BACKUP SWITCHING IC

Rev.3.1_01
BATTERY BACKUP SWITCHING IC
S-8425 Series
 Precautions
• In applications in which any one of IRO, IOUT, or ICH is small, the output voltages VRO, VOUT_{, and VCH} may
rise, causing the load stability to exceed standard levels. Set I_RO, I_{OUT, or ICH} to 10 μA or more.
• Attach the proper capacitor to the VOUT pin to prevent the RESET voltage detector (which monitors the
VOUT pin) from becoming active due to undershoot.
• Watch for overshoot and ensure it does not exceed the ratings of the IC chips and/or capacitors
attached to the VRO, VOUT, and VCH pins.
• Add a 10 μF or more capacitor to the VOUT, VRO, and VCH pins.
• Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in
electrostatic protection circuit.
• SII Semiconductor Corporation claims no responsibility for any and all disputes arising out of or in
connection with any infringement by products including this IC of patents owned by a third party.
 Application Circuit
When Using Secondary Battery as Backup Battery
+
10 μF
+
10 μF
+
10 μF
6V
0.1 μF
3V
VCH VOUT
VIN
S-8425 ^VRO
Series
VBAT
CS
100 kΩ
RESET
VSS
VCC
100 kΩ
+
10 μF
Microcontroller
INT
RESET
Caution
The above connection diagram and constant will not guarantee successful
operation. Perform thorough evaluation using the actual application to set the
constant.
Remark The backup battery can be floating-recharged by using voltage regulator 3.
Figure 26 Application Circuit
29