Other Circuits; Power Supply Circuit - Citizen CL-E700 series Technical Manual

Chapter 2 Operating Principles
2-2.
Operation of Control Parts

2-2-6. Other circuits

(1) Power supply circuit

+24V DC is supplied from the "Unit Power Supply" to the "SA Main PCB".
U19 is the switching regulator IC to produce +5V DC from +24V DC. U20 is the switching
regulator IC to produce +3.3V DC and +1.2V DC from +5V DC.
Each produced voltage is supplied to the following circuits.
+24V DC: For driving circuits (motors, print head, buzzer and cutter (option)) and I/F circuits
+5V DC: For sensors, power to the head logic circuit, operation panel, fan, I/F circuits
(option) and peeler (option)
+3.3V DC: For logic circuits
*1.2V DC: For the CPU and FPGA
J13
R130
1
STANDBY
2
GND
3
GND
4
GND
5
GND
6
+24V
7
+24V
8
+24V
9
+24V
From
Unit Power
Supply
V3CE
(Fixed to "H")
[SA Main PCB]
* In power saving mode, +3VIO and +5VIO are not supplied to the subsequent circuits.
Power saving circuit:
When the printing standby state continues for a certain period of time, the printer automatically
enters the power saving mode. In this mode, +24V DC output from the "Unit Power Supply"
reduces to +9V DC and the power consumption of the printer becomes minimum.
The period from entering the printing standby to entering the power standby mode is
changeable with the "Standby Timer" of the "System Setup Menu".
During the power saving mode, if print data is received or any key operation is done, +9V DC
output from the "Unit Power Supply" resumes +24V DC and the printer automatically returns to
the normal mode.
* By setting the "LCD Standby" of the "System Setup Menu" to ON, the LCD display turns off
for further power saving when the printer enters the power saving mode.
CL-E700 series
Q17
L: Power Saving mode
DTC114EM
H: Normal mode
R134
+5V Regulator
U19
DC-DC Converter
+24V
2
3
VIN SW
C147
+
5
FB
C155
NR119E
+3.3V / 1.2V Regulator
U20
DC-DC Converter
7
8
VIN1
LX1
1
VIN2
2
6
LX2
EN1
12
EN2
PAM2306AYPKB
nPWRSAVE
Q21
MCH6342
R143
R146
Q23
R148
DTA115TM
R149
+3.3V
+1.2V (To CPU & FPGA)
U5
FPGA
N2
V3IOON
22_N2
R150
2-38
U5
FPGA
22-P2
P2
Power Saving
Q22
MCH6342
+5V
R144
R147
Q24
DTC114EM
Power Saving
Q25
MCH6342
R153
R154
Q26
DTC114EM
+5VIO
+3VIO