CHANGE with LOWER Voltage Solid Caps

[mikail13]

my Philips 190X LCD sometimes do not work.

5 caps blown.
2x 220uF 25v
3x 470uF 25v Capxon.

could i use 470uF 16v and 270uF 16v Solid caps.

[ReeceyBurger123]

Re: CHANGE with LOWER Voltage Solid Caps

No always use the same voltage caps.

[mikail13]

Re: CHANGE with LOWER Voltage Solid Caps

No always use the same voltage caps.

but mobo manufacturer uses lower solid caps on VRM.

we can use 560 uF 2.5v solid caps instead of 680uf 4v liqid caps.

[stj]

Re: CHANGE with LOWER Voltage Solid Caps

only necause they dont make 2.5v liquid caps

[ReeceyBurger123]

Re: CHANGE with LOWER Voltage Solid Caps

Unless you know the voltage of the circuit use whats there or if you have one thats above rated voltage of the board use it.

[budm]

Re: CHANGE with LOWER Voltage Solid Caps

190X??? 5?, 6?, 7?



http://elektrotanya.com/philips_190x5.rar/download.html

[stj]

Re: CHANGE with LOWER Voltage Solid Caps

220uf 25v polymer
https://cdn.badcaps-static.com/pdfs/...5fa978066b.pdf

it's going to be cheaper to use pansonic FR series.

[mikail13]

Re: CHANGE with LOWER Voltage Solid Caps

it's philips 190X7FB.

i used
one 470uF 16v solid.
one 270uF 16v solid.
other's 470 uF 16v nichicon 105 C , and 220uF 25V .

your links dead.

190X??? 5?, 6?, 7?



http://elektrotanya.com/philips_190x5.rar/download.html

[budm]

Re: CHANGE with LOWER Voltage Solid Caps

it's philips 190X7FB.

i used
one 470uF 16v solid.
one 270uF 16v solid.
other's 470 uF 16v nichicon 105 C , and 220uF 25V .

your links dead.

I have no problem with the links in post #6, the file is too big to be upload to B.C.

[Th3_uN1Qu3]

Re: CHANGE with LOWER Voltage Solid Caps

In essence there is no problem with 16v caps there, as small computer monitors use 12v for the inverter. However, only the 5v rail for the logic is regulated in these supplies, and with no load (in standby) the 12v will get up to 14v, sometimes a bit higher.

Polymer caps are less tolerant to overvoltage than regular lytics. And their typical failure mode is short, so if your monitor suddenly stops working, you'll know why.

[mikail13]

Re: CHANGE with LOWER Voltage Solid Caps

monitor is OK now.

but top panel line is hot (app. 40-45 C) than low line.

i think top CCFL is overheating.


why?

[stj]

Re: CHANGE with LOWER Voltage Solid Caps

if you want to strip it out, you could resolder the pins.

[mariushm]

Re: CHANGE with LOWER Voltage Solid Caps

Don't use capacitors rated for lower voltages on monitor power supplies, especially for the part of the power supply designed for fluorescent bulbs.

The voltage on lots of old monitors is usually around 12v, some use bigger voltages, some have fairly unregulated power supply (for example they may go up to around 15v-18v and then stabilize in a few seconds at something like 14v, so it's not safe to use 16v rated capacitors)
On motherboards, especially at the VRM circuit near the cpu socket, it's often possible to replace electrolytic capacitors with polymer capacitors rated for lower voltages because you actually know processors work with <1v .. 1.2v. Motherboard manufacturers used multiple electrolytic capacitors in parallel with higher than required capacitance and rated for 6.3v or 10v in order to have a much lower ESR (bigger capacitors often equals lower esr)
For this reason, it's possible to use 2.5v or 4v rated polymer capacitors of slightly lower capacitance in the VRM - you know the output voltages are lower than 2.5... 4v always.

If you don't know the supposed output, what voltage should be on that capacitor, stick with the capacitance and votage ratings of the old capacitor.