If a diode rated for reverse voltage of 30v fails and all you have is a 20v would it safely work?
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Re: Can diode be replaced with a lower voltage rating?
depends on the circuit -
Re: Can diode be replaced with a lower voltage rating?
indeed, depends on if the circuit was overrating it, but chances are that it wasn't, and the PRV was selected for a reason.Comment
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Re: Can diode be replaced with a lower voltage rating?
Probably can get away with a lower voltage then, but don't be surprised if it dies again...Comment
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Re: Can diode be replaced with a lower voltage rating?
IMHO you should stick with 30v, unless you really investigate the circuit thoroughly.
The 6+ may use better binned leds (with lower forward voltage), or the 6+ may have fewer leds in series, allowing for lower voltage, or the 6+ could use a better backlight driver which may not "overshoot" as much (maybe runs at higher frequency, maybe has faster/better feedback etc)Comment
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I'd like to start out by thanking this forum for providing the info to be able to repair my 15 year old CP1500AVRLCD UPS. Here is all the info I gathered during my trouble-shooting and re-capping.
Like clockwork, I've had to replace the SLA batteries every 4 years. It was about that time and the UPS was acting like it needed new batteries... randomly shutting off with AC present, not being able to charge fully, and poor runtime when AC was removed. So, I replaced the batteries but noticed that it was not charging properly.
I decided to verify that the batteries were... -
Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
Upon bringing it home and plugging it up, it showed a standby light.
I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.
The screen seems to blackout and stay black, but with a flashlight I can see the display.
With my Playstation 4 connected via HDMI, and running a game I can hear sound.
Assuming... -
Have an A2141 which is reading about 5.2V 0.07A on all USB jacks, started doing the measurements.
PPBUS_3GH diode: measures good .45V
PPBUS_3GH Voltage: maybe not so good 12.25V maybe bad T2? Unit did not come up in DFU on configurator.
The weird so far is
PP3v3_G3H_RTC_X diode: .104V (WTF?)
PP3v3_G3H_RTC_X voltage: 3.39V (Normal)
Stopped there attempted reverse voltage injection at PP3v3_G3H_RTC_X with 1V. Instead of the circuit sinking any current, My PSU suddenly reads 3.4V with no current draw.
Not sure what any of this means... -
Hi. Recently serviced a damaged A1466 Macbook Air. Thought to post the issues and resolution for each.
Macbook AIR Model A1466 Diagnostic 09-01-2021
Issue: Liquid damaged (beer spill) Macbook AIR will not power up.
Problems & Resolutions
1) Attached Apple magsafe power adapter. No green / no orange light. This confirms the absence of the PP3V42_G3H voltage rail. The PP3V42_G3H rail is the primary voltage rail necessary to communicate with the magsafe power adapter to report the green or orange light status to the end user....09-01-2021, 09:31 AM -
Hello guys,
recently I watched Richard's video on YT (Learn Electronics Repair channel) with an explanation why lower input voltage than rated can also kill electronics components.
The vide can be shown here.
Now, I would like to learn more and I'm not sure that I understood exactly why this is happening.
It is clear to me that PWM chip will keep MOSFTES switched On longer (duty cycle is longer) and that they will dissipate more heat. I think this is not the main reason because MOSFET can probably work switched on for a long time. It is also possible that output...12-26-2022, 12:45 AM
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