18 SuPPlY VOlTaGe DeTeCTiOn CiRCuiT (SVD)
S1C17153 TeChniCal Manual
Seiko epson Corporation
18-1
(Rev. 1.0)
Supply Voltage Detection Circuit
18
(SVD)
SVD Module Overview
18.1
The S1C17153 includes an SVD (supply voltage detection) circuit to monitor the power voltage supplied to the V
DD
pin. It can be used to check whether the power supply voltage drops below the detection level set with software or
not. The following shows the features of the SVD module:
• Power supply voltage to be detected: V
DD
• Detection voltage levels:
13 levels (1.98 V to 3.18 V)
Figure 18.1.1 shows the SVD configuration.
V
DD
Internal data bus
Voltage
comparator
Comparison
voltage
setting circuit
Detection
result
SVDDT
SVD
SVDEN
SVDC[4:0]
1.1 SVD Configuration
Figure 18.
Comparison Voltage Setting
18.2
The SVD circuit compares the power supply voltage (V
DD
) against the comparison voltage set by software and out-
puts results indicating whether the power supply voltage exceeds this comparison voltage. The comparison voltage
can be selected from among the 13 levels listed in Table 18.2.1 with the SVDC[4:0]/SVD_CMP register.
2.1 Comparison Voltage Settings
Table 18.
SVDC[4:0]
Comparison Voltage
SVDC[4:0]
Comparison Voltage
0x1f
Reserved
0xf
2.08 V
0x1e
0xe
1.98 V
0x1d
0xd
Reserved
0x1c
0xc
0x1b
0xb
0x1a
3.18 V
0xa
0x19
3.08 V
0x9
0x18
2.98 V
0x8
0x17
2.88 V
0x7
0x16
2.78 V
0x6
0x15
2.68 V
0x5
0x14
2.58 V
0x4
0x13
2.48 V
0x3
0x12
2.38 V
0x2
0x11
2.28 V
0x1
0x10
2.18 V
0x0
(Default: 0x0)
note
: The comparison voltage is effective only when it is set within the operating voltage range. If the
comparison voltage set is out of the operating voltage range, no correct detection results will be
obtained.