s-8424a Seiko Instruments Inc., s-8424a Datasheet - Page 30

• Manufacturer Part Number: s-8424a
• Description: Battery Backup Switching Ic
• Manufacturer: Seiko Instruments Inc.

30
BATTERY BACKUP SWITCHING IC
S-8424A Series
Precautions
Application Circuits
• In applications with small I
• Attach the proper capacitor to the VOUT pin to prevent the RESET voltage detector (which monitors the VOUT
• Watch for overshoot and ensure it does not exceed the ratings of the IC chips and/or capacitors attached to the
• Add a 10 μ F or more capacitor to the VOUT and VRO pins.
• When V
• Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in
1. When Using Timer Micro controllers for Backup to display PREEND in the primary CPU
exceed standard levels. Set I
pin) from coming active due to undershoot.
VRO and VOUT pins.
even when V
sure to take the 4 ms interval or more after the rise of V
electrostatic protection circuit.
IN
rises from the voltage more than V
6 V
BAT
3 V
is more than the PREEND release voltage. Thus when monitoring the PREEND pin, make
Main CPU
0.1 μ F
10
1 k Ω
VCC
μ
10 μ F
RO
F
RO
RESET
or I
and I
100 k Ω
+
INT
+
OUT
VRO
VBAT
VIN
, the output voltages V
OUT
Seiko Instruments Inc.
Figure 23 Application Circuit 1
to 10 μ A or more.
S-8424A
Series
VOUT
VSS
SW1
, a low pulse of less than 4 ms flows through the PREEND pin
PREEND
RESET
CS
IN
.
Address data
+
100 k Ω
RO
10 μ F
and V
OUT
may rise, causing the load stability to
100 k Ω
CS
RESET
microcontroller
VCC
Timer
Rev.2.2
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