Instructables

High Voltage Power Supply from Laser Printer

Picture of High Voltage Power Supply from Laser Printer
Laser Printers are treasure troves of electronic goodies from gears to lasers to high voltage power supplies. High voltage is required in laser printing to create electrostatic charges to determine where the toner sticks, creating letters and images on paper. However, modern laser printers with their power saving designs and multiple safety features makes the power supply unusable unless connected to the cpu on the laser printer itself. Today, I will be showing you how you can trick the power supply into giving out juicy high voltage with just a bit of soldering.


SAFETY: Do not touch the circuit board when it is connected to mains voltage. Many heatsinks are live and will give you a dangerous and nasty shock from the mains. This is even deadlier than the high voltage produced by the power supply.

The printer i will be using is a SAMSUNG ML-1670. Its power supply outputs 4 different voltages.
1)Transfer High Voltage (THV+)
- Input Voltage : 24 V DC ± 15%
- Output Voltage : THV+: max +3.5kV ± 10 %,(Duty Variable, no loading ) @ 6.5uA
THV-: -1kV±20% (when cleaning,200 ㏁)
- Output Voltage Control Method : Transfer Output Voltage is outputted and controlled by changing Duty of
THVPWM Signal.

2) Charge Voltage (MHV)
- Input Voltage : 24 V DC ± 15%
- Output Voltage : -1.0KV ~ -1.8KV DC ± 3% @ 26uA
- Output Control Signal(MHV-PWM) : CPU is HV output when PWM is Low

3) Developing Voltage (DEV)
- Input Voltage : 24 V DC ± 15%
- Output Voltage: -200V ~ -500V DC ±3% @ 8.6uA
- Output Loading range : 10MΩ ~ 1000 MΩ
- Output Control Signal (BIAS-PWM) : the CPU output is HV output when PWM is low.

4) Supply
- Output Voltage : -350 V ~ -650V DC ±50 V(ZENER using, DEV ) @ 11.6uA
- Input contrast of the output stability degree : under ± 5 %
- Output Loading range : 10 MΩ ~ 1000 MΩ
- Output Control Signal (BIAS-PWM) : the CPU is HV output when PWM is low.
 
Remove these adsRemove these ads by Signing Up
Pro

Get More Out of Instructables

Already have an Account?

close

PDF Downloads
As a Pro member, you will gain access to download any Instructable in the PDF format. You also have the ability to customize your PDF download.

Upgrade to Pro today!