View previous topic :: View next topic |
Author |
Message |
Guest
|
Posted: Sat Jun 10, 2006 1:14 am Post subject: Switched mode power supply (SMPS) how to check |
|
|
How to find out wheter a SMPS type power supply is dead or not? This SMPS is fitted in a VCR. The output pins on the SMPS has voltage. When it is plugged in a very weak ticking (2Hz) is possible to hear. |
|
Back to top |
|
|
vtech
Joined: 08 May 2006 Posts: 1264 Location: USA
|
Posted: Sat Jun 10, 2006 9:24 am Post subject: |
|
|
In general, with SMPS there are switched & unswitched lines.
Unswitched lines are usally one or two unregulated supply lines that will run as soon as the unit is plugged in, however the switched lines are controlled by means of a "power on" signal pin that comes from the syscon. It's possible that your unswitched lines are either low or loaded down--therby hearing the ticking sound.
Or it can easily be related to dried up electrolytic caps causing too much AC floating throughout the circuit. |
|
Back to top |
|
|
|
|
|
You can post new topics in this forum You can reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
eServiceInfo on FB -
Service Manuals Free Download -
Service Diagrams
Free TV Schematics Download -
HARDW.net -
Pinout Master -
Jabse Service Manual Search -
Jabse.InK -
onTap.bg
SnimkiOt.com -
Poblizo.com : пътешествия
Latest Service Manuals :
ntmfs4939n-d ON Semiconductor • VR6290 Philips • 2sd560 Fuji • dumblenotes DUMBLE • bd135 bd136 bd139 bd140 ST • HD 7262/F Philips • LC89056W-E Pioneer • 30070-90009 S33 schem Jan79 HP • HP NC8000 [RUBY1.0,Inventec] notebook sc • hfe mitsubishi da-u540 u640 service de M •
|