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EPSON
S1C6F567 TECHNICAL MANUAL
CHAPTER 6: DIFFERENCES FROM MASK ROM MODELS
6.6 SVD Circuit
The S1C6F567 has a built-in SVD (Supply Voltage Detection) circuit with the same configuration as that of
the mask ROM model (S1C635xx). However, the mask option is fixed at "with external voltage detection".
Table 6.6.1 lists the criteria voltages.
Table 6.6.1 SVD criteria voltage list
SVDS3
0
1
SVDS0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
SVDS1
0
1
0
1
0
1
0
1
SVDS2
0
1
0
1
S1C6F567
1.05 (external voltage)
–
2.80
2.90
3.00
3.10
3.20
3.30
Criteria voltage (V)
S1C635xx
2.20 / 1.05
2.20
2.30
2.40
2.50
2.60
2.70
2.80
2.90
3.00
3.10
3.20
3.30
A criteria voltage can be set using the SVDS0–SVDS3 register (FF04H).
Since the minimum operating voltage of the S1C6F567 is 2.7 V, 2.7 V or less criteria voltages are not
available. Be aware that the SVD circuit in the S1C6F567 may not operate when a 2.7 V or less criteria
voltage is selected.
For the software control sequence of the SVD circuit, refer to the "S1C635xx Technical Manual".
6.7 Telephone Function (Tone/Pulse Dialer)
____
DP terminal:
_____
In the S1C63557and S1C63567, output specification for the DP terminal is selected from between "comple-
mentary output" and "Nch open drain output" by mask option; in the S1C6F567, outpu specification for
_____
the DP terminal is fixed at "complementary output".
DTS selection (FF16HD2):
In the S1C63557, the minimum tone duration time (
tTD) is 94 msec (No DTS selection); in the S1C63567,
the minimum tone duration time (
tTD) can be selected as 94 msec or 47 msec, or only 94 msec which
depends on the mask option (that means selecting DTS or not); in the S1C6F567, DTS is always selected,
so the minimum tone duration time (
tTD) can be selected as 94 msec or 47 msec.