RS5C313 RICOH Co.,Ltd., RS5C313 Datasheet - Page 21

• Manufacturer Part Number: RS5C313
• Description: Ultra-compact Real-time Clock Ic
• Manufacturer: RICOH Co.,Ltd.

8.2 Pulse Mode Interrupt
When the CT3 bit is set to 0 and provides four interrupt cycles, off, on, 1024 Hz, and 2 Hz can be selected. The
CTFG bit cannot be set because it is used for output monitoring.
8.3 Level Mode Interrupt
When the CT3 bit is set to 1, clock-interlocked cycles in increments of 1 second to 1 month can be selected. The
CTFG bit can be written; writing the CTFG bit switches the INTR pin to the low level while writing 0 to the CTFG
bit turns off the INTR pin.
9. Typical Application
CTFG
1)
2)
3)
INTR
CTFG
INTR
Connect the capacitance of the oscillation circuit to the VSS pin.
Mount the high- and low-frequency by-pass capacitors in parallel and very close to the RS5C313.
Connect the pull-up resistor of the INTR pin to two different positions depending on whether the resistor is in use during bat-
tery back-up.
When not in use during battery back-up - - - - - Position A in the above figure
When in use during battery back-up - - - - - - -- Position B in the above figure
C P U
(Second count-up)
Interrupt
VCC
System supply
VSS
voltage
0.488ms
T1
(Second count-up)
Interrupt
INTR
CE
SCLK
SIO
Writing 0 to CTFG bit
R S 5 C 3 1 3
OSCOUT
OSCIN
VDD
VSS
1024Hz : T1=0.977ms
B
2Hz : T1=500ms
A
System supply
voltage
RS5C313
21