Circuit Operation; C229Psb/Pse/Psh Power Supply Circuit - Epson FX 890 - B/W Dot-matrix Printer Service Manual

2.3 CIRCUIT OPERATION

2.3.1 C229PSB/PSE/PSH Power Supply Circuit

This printer can be powered by one of the following three power supply boards: the C229PSB
(120V) board, the C229PSE (230V) board, or the C229PSH (Universal) board. The function of the
boards is the same , except for a difference in the primary circuitry. The power supply outputs the
DC current necessary to drive the printer control circuit and drive the mechanism. The input
voltages and fuse ratings are as shown in the following table:
Board
C229PSB
C229PSE
C229PSH
The power supply circuit outputs voltages used to drive the various control circuits and the
mechanism, as shown in the following table:
F
5V 5% 0.7A
(Type-B I/F output is included.)
F
35V
The power supply circuit consists of the line filter circuit, ZC-RCC (Zero-Cross Ringing Choke
Converter) switching circuit and 5V chopper regulator IC. The AC voltage is first input to the line
filter circuit for higher harmonics absorption, then input to the switching circuit and transformed to
+35VDC. +5VDC is generated from +DC35V by the regulator IC. The over current / voltage
protection circuit is also designed on the board.
The power switch set in the secondary circuit that is controlled by the signal PSC from the control
panel.
Rev. B
Table 2-1. Input Voltage and Fuse Rating
Input Voltage
85-138VAC
187-276VAC
85-276VAC
Table 2-2. Output Voltages and Applications
Output Voltage
6% 0.8A
Figure 2-4. Power Supply Circuit Block Diagram
FX-1180/FX-880 Service Manual
Chapter 2 Operating Principles
4A, 125V or 250V
T2.0AH, 250V
T4.0AH, 250V
Applications
Logic lines
Detectors
Panel Switches & LEDs
CR Motor
PF Motor
Printhead
Fuse F1 Rating
2-4