Infocus power supply isssue

[budm]

Re: Infocus power supply isssue

That is an Opto-isolator, it is used for feeding the feedback signal to the primary circuit to regulate the output voltage. So right now, you are just running the board with nothing else attached but only the AC input.

[subarub4]

Re: Infocus power supply isssue

That Diode D103 is in parallel with the low value resistor R130 (the value can be from 10~100 Ohms) and connected to the Gate of the MOSFET, the diode is for fast discharging the MOSFET's Gate capacitor when the drive signal goes low to make sure the MOSFET turns off fast.
Looks like there are more things to check.

I'm curious why IC203 has no voltage but IC204 has 2.8V on two pins, one thing is how would I know the receiving side is working?

Do you happen to know who makes this? I want to say Fairchild but I lost the info on it..
The chip has this on it:

L1211
817 BW

Wait.. never mind found it here

H11A817BW

http://pdf1.alldatasheet.com/datashe...H11A817BW.html

[budm]

Re: Infocus power supply isssue

That Diode D103 is in parallel with the low value resistor R130 (the value can be from 10~100 Ohms) and connected to the Gate of the MOSFET, the diode is for fast discharging the MOSFET's Gate capacitor when the drive signal goes low to make sure the MOSFET turns off fast.
Looks like there are more things to check.

[subarub4]

Re: Infocus power supply isssue

I found a diode that's reading both ways.. my microSD card seems to have walked off so I can't get a macro shot right now but it's D103 on the backside of the board, SMD mount the cathode is connected to Q602 & Q603

[subarub4]

Re: Infocus power supply isssue

Still not working and the MR4010 still heats up as soon as it's plugged in.

[subarub4]

Re: Infocus power supply isssue

Are those two caps PANASONIC EB series?

Yes

[budm]

Re: Infocus power supply isssue

Are those two caps PANASONIC EB series?

[subarub4]

Re: Infocus power supply isssue

I can say right now the new chip has no resistance between the drain and source like the current one right now.

[subarub4]

Re: Infocus power supply isssue

[subarub4]

Re: Infocus power supply isssue

Changed the caps today no change.. so still waiting on the MR4010 to arrive.

As you can see those 2 1000 uF 25V caps I ended up ordering the wrong diameter kind.

[subarub4]

Re: Infocus power supply isssue

Yeah that's what I did

I ended up ordering the same batch of caps but this time from Mouser so I'm going to have two sets.. if the Mouser order ever comes then good.. if not they are lost someplace :-/ if they end up coming later then I will have some caps I can get rid of.

It would be a shame if my MR4010 from China beat out Digikey from MN..

[Khron]

Re: Infocus power supply isssue

I don't think they make any "low ESR" high-voltage series Just pick the one with the best balance of ripple current rating vs. price (in case price is an issue; if not, go for the highest ripple, in a case size that fits your application )

[subarub4]

Re: Infocus power supply isssue

Speaking of caps for the 150 Uf 450v cap should I pick a low ESR one?

[subarub4]

Re: Infocus power supply isssue

Still waiting on those caps :-/

[subarub4]

Re: Infocus power supply isssue

Btw I have a oscilloscope

[subarub4]

Re: Infocus power supply isssue

By the way, you should also replace the set of caps since the projector runs pretty hot.

Yep I have the following Panasonic caps coming from Digikey should be here by Saturday I hope

CAP ALUM 47UF 25V 20% RADIAL
CAP ALUM 10UF 50V 20% RADIAL
CAP ALUM 47UF 35V 20% RADIAL
CAP ALUM 22UF 50V 20% RADIAL
CAP ALUM 1000UF 25V 20% RADIAL (2)
CAP ALUM 150UF 450V 20% SNAP

[budm]

Re: Infocus power supply isssue

By the way, you should also replace the set of caps since the projector runs pretty hot.

[subarub4]

Re: Infocus power supply isssue

Coincidence?

http://www.eevblog.com/forum/chat/smps-help/

No, this site has been pretty helpful Out of the 4-5 sites I posted my question at only this and that site really had info on SMPS.
Plus should anyone else search on google they can find helpful info, since all the power supplies before me were all for older Infocus projectors which did not have a power supply as mine.

[retiredcaps]

Re: Infocus power supply isssue

Coincidence?

http://www.eevblog.com/forum/chat/smps-help/

[subarub4]

Re: Infocus power supply isssue

You have to use VA rating since the load (the projector) is not linear load, so 2.6A x 120V = 312VA, and you will be using 625VA, then you are OK.

Ah got it!

I will just get a 1000VA model since I rather have a little backup.. I've seen times were the power will come on for a few seconds then back off again.