Battery Circuit - Sam4s ER-380M Service Manual

7 Special Circuit Descriptions
7-3 Battery, RTC(Clock), Buzzer, Cash Drawer and VFD Circuits

7-3-1 Battery Circuit

Battery Circuit supplies SRAMs and RTC (U14, RS5C372A) with voltage source and is used to drive clock and to save
data when the main Power is turned off. When the Power is turned on, VCC source(+5VDC) is supplied to SRAMs and
RTC through the D14(SK14), and the Battery is charged. When the Power is turned off, D14 is shut and the source
charged in the Battery is supplied to SRAM and RTC.
7-3-2 RTC(Clock) Circuit
This uses an Clock IC RS5C372A, is driven by the Battery when the main Power is turned off.
7-3-3 Buzzer Driving Circuit
The Buzzer is used to inform several kinds of states which occur under system operating and gives some information to
users by controlling the P8.0 pin of CPU. The frequency of buzzer is 2[KHz]
7-4
VC C
W hen Pow er O n,
VBT Suppl y
D 16
D I O D E- SK14
D 18 D 28
D I O D E- M 4 D I O D E- SK14
V67
W hen Pow er O n, Bat t er y C har gi ng
Figure 7-3 Battery Circuit
VC C VC C
R 55
R 51
4. 7K
4. 7K
100 R 92
R TC _SC LK
100 R 96
R TC _SD A
Figure 7-4 RTC Circuit
D 11
M M BD 6050LT1
Q 22
M M BT2222A
R 86
4. 7K
V69
1
BU ZZER
R 89
10K
Figure 7-5 Buzzer Circuit
VBT
W hen Pow er O f f ,
VBT Suppl y
D 13
D I O D E- SK14
VC C
R 104
270
R 105
10K
D I O D E- SK14
16V
AD C _BAT
C 92
D 14
100uF
BAT1
3. 6V
VBT
U 14 X2
32. 768KH z
1 8
I N TR B VD D
2 7
V65
SC L O SC I N
3 6
V66
SD A O SC O U T
4 5
VSS I N TR A
R S5C 372A
VD R V VC C
R 91
100
R 90
100
3
2
AU 1
BU ZZER
SAM4S ER-380M/F SERIES