R2025S/D
• Connection of /INTRA and /INTRB Pin
The /INTRA and /INTRB pins follow the N-channel open drain output logic and contains no protective diode on the
power supply side. As such, it can be connected to a pull-up resistor of up to 5.5 volts regardless of supply
voltage.
System power supply
*1) Depending on whether the /INTRA and
/INTRB pins are to be used during battery
backup, it should be connected to a pull-up
resistor at the following different positions:
A
/INTRA or /INTRB
*1)
(1) Position A in the left diagram when it is not to
be used during battery backup.
(2) Position B in the left diagram when it is to be
B
Backup power supply
used during battery backup.
VDD
VSS
Connection of 32KOUT Pin
As the 32KOUT pin is CMOS output, the power supply voltage of the R2025S/D and any devices to be connected
to the 32KOUT should be same. When the devices is powered down, the 32KOUT output should be disabled.
When the CLKC pin is connected to the system power supply through the pull-up resistor, the pull-up resistor
should be 0Ω to 10kΩ, and the 32KOUT pin should be connect to the host through the resistor (approx. 10kΩ).
System power supply
0 to10KΩ
RN5VL
XXC
System power supply
CLKC
CLKC
Host
32KOUT
32KOUT
Approx. 10KΩ
Back-up power supply
Back-up power supply
VDD
VSS
VDD
VSS
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RICOH [ RICOH ELECTRONICS DEVICES DIVISION ]
