Stylus C40UX/C40SX/C20UX/C20SX | Revision A |
+36VDC +5VDC | ZD53 |
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+5VDC line over voltage limitation
+36VDC over | F51 | |
current protection | ||
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ZD52,87
+36VDC line over voltage
limitation ZD51,R92,93,Q91
+36VDC Line Constant Control
The C417 PSB/PSE board has the various control circuits to stop voltage output if a malfunction occurs on the power supply board or the main board while the printer mechanism is on duty. Following explains each control and protection circuit.
+36V line constant voltage control circuit: |
The output level of +36V line is monitored by a R92, R93,Q91,ZD51. |
When + 36V line reaches about 36.4V, ZD51 has a continuity with and PC1 start |
the operation via Q91. Consequently, Q1 switching operation is controlled by this |
circuit to stabilize the 36V line. |
+36Vline over voltage protection circuit: |
The output voltage line is monitored by ZD52,ZD87. If the output level of the |
voltage level of +36DC line exceeds +48V, this circuit stops the operation of the |
switching FET Q1 via PC1,Q82,Q83 and prevents high voltage from applied to the |
secondary side |
+36Vline over current protection circuit: |
The output voltage is monitored by the F51. When the abnormal current is |
C51
Smoothing |
Circuit |
TRANS(T1)
Smoothing | Main |
Circuit | Switching |
PC1
Photo |
Coupler |
Feed back circuit
detected by F51, F51 is fused and cut off the +36V line output to the Main board |
+5V line over voltage protection circuit: |
The output voltage level of the +5V line is monitored by ZD53. |
If the output level of the voltage level of +5DC line exceeds +7V, this circuit |
stops the operation of the switching FET Q1 via PC1,Q82,Q83and prevents high |
voltage from applied to the secondary side. |
Over Current | Filter Circuit | Full Wave | |
Protection | rectifier circuit | ||
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Figure 2-20. C417 PSB/PSE Board Block Diagram
Operating Principles | Electrical Circuit Operating Principles | 42 |
