Power Supply; Low-Voltage Power Supply - Brother MFC8440D Service Manual

7/13/2019
1.5

Power Supply

1.5.1

Low-voltage power supply

The power supply uses a switching regulation system to generate the regulated DC power
(+3.3V, +8V [non regulated] and +24V), which are converted from the AC line.
The regulated output is listed below;
Regulated Output
+3.3V / 1.5A
+8V / 0.4A
+24V / 2.2A
For the circuit diagram of the low-voltage power supply PCB, see
'LOW-VOLTAGE POWER SUPPLY PCB CIRCUIT DIAGRAM'
Fuse
Lightning
Surge
Absorber
http://slidepdf.com/reader/full/brother-8840d-service-manual
Fuse
Line
Rectifier
Filter
24V
Regulation
Circuit
3.3V
Regulation
Circuit
Brother 8840D Service Manual
MFC-8440/8840D/8840DN, DCP-8040/8045D/8045DN
APPENDIX 4.16 or 4.17
in this manual.
(Heater)
Thermal
Fuse
Heater
Circuit
Feedback
Oscillator
(Engin Circuit / Main Circuit)
24V
8V
3.3V
Fig. 3-17
3-11
SERVICE MANUAL
Lamp
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