RV5C339A_03 Datasheet, PDF (13/46 Pages) RICOH electronics devices division – 3-WIRE SERIAL INTERFACE REAL-TIME CLOCK IC WITH VOLTAGE MONITORING FUNCTION

RV5C339A
2.2 Control Register 2 (at Address Fh)
D7
VDSL
D6
D5
D4
VDET SCRATCH XSTP
D3
CLEN1
VDSL VDET SCRATCH XSTP CLEN1
0
0
0
1
0
D2
CTFG
CTFG
0
D1
WAFG
WAFG
0
D0
DAFG (For writing)
DAFG (For reading)
0
Default setting*
*^{) Default settings: Default value means read/written values when the XSTP bit is set to “1” due to power-on from 0 volts or supply voltage drop.}
2.2-1 VDSL
Supply Voltage Monitoring Threshold Selection Bit
VDSL
Description
0
Selecting the supply voltage monitoring threshold setting of 2.1 volts.
1
Selecting the supply voltage monitoring threshold setting of 1.6 volts.
The VDSL bit is intended to select the supply voltage monitoring threshold settings.
(Default setting)
2.2-2 VDET
Supply Voltage Monitoring Result Indication Bit
VDET
0
1
Description
Indicating supply voltage above the supply voltage monitoring threshold settings. (Default setting)
Indicating supply voltage below the supply voltage monitoring threshold settings.
Once the VDET bit is set to 1, the supply voltage monitoring circuit will be disabled while the VDET bit will hold the
setting of 1. The VDET bit accepts only the writing of 0, which restarts the supply voltage monitoring circuit.
Conversely, setting the VDET bit to 1 causes no event.
2.2-3 SCRATCH
Scratch Bit
SCRATCH
0
1
Description
(Default setting)
The SCRATCH bit is intended for scratching and accepts the reading and writing of 0 and 1. The SCRATCH bit will
be set to 0 when the XSTP bit is set to 1 in the control register 2.
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