MMC6100B 25 Sub needed

[mu2]

Hi,

I'm working on a Samsung LNS3241DX/XAA that has vertical lines at times.
Already checked the power supply capacitors.
I was able to find that the regulator on the T-con (MMC6100B-25) has a good 3.3 volt input but the output is 1.7 volts.
I cannot find the spec sheet on the net.
Is there a 2.5 regulator substitute that has the same case style and pin outs?
Something stocked by Digikey would be great.

Thanks in advance,

Mike

[budm]

Re: MMC6100B 25 Sub needed

3.3Vin for 2.5V REG is pretty low, only 0.8V drop out voltage, most I have seen is about 1.2V drop out range. 0.8V does not sound right, I cannot locate data sheet for this regulator either.

[tom66]

Re: MMC6100B 25 Sub needed

I have seen LDOs with a 0.1V dropout voltage. An LD1117 will usually manage 0.8V at low load current.

[budm]

Re: MMC6100B 25 Sub needed

Wow, 0.1V, how the heck do you get the headroom for regulation.

[tom66]

Re: MMC6100B 25 Sub needed

I have used this before.

500mA with about 200mV dropout.

Not used this myself, but am considering it for maximum battery life on a widget running off two coin cells (the problem is two coin cells would slightly exceed the maximum VIN) - 50mV dropout:
http://www.ti.com/product/tps72215

Linear has a 1.5A LDO with a 100mV dropout, although the price is high, because Linear do that...

[mu2]

Re: MMC6100B 25 Sub needed

Thanks for the responses.
I think I found something.


Digikey has them as 576-3601-5-nd
Can anyone verify this as a good sub?

Mike

[mu2]

Re: MMC6100B 25 Sub needed

Forgot to mention that it looks like that the original part is rated at 1.3 amps.
The Micrel part is listed at 1.5 amps.

Mike

[mu2]

Re: MMC6100B 25 Sub needed

Hi,

Just wanted to update the previous post.
I replaced the 2.5 volt regulator on the t-com board with Digikey 576-3601-5-nd.
The output had been 1.7 volts and the set has been on for over an hour with a good picture.
I also replaced the Capxon power supply capacitors for good measure.
The symptom was fine vertical lines that sometimes filled the screen or at times only in the upper 1/4 of picture. Usually the picture started out ok but worsened but it would also be poor when initially turned on.

Mike

[budm]

Re: MMC6100B 25 Sub needed

Hi,

Just wanted to update the previous post.
I replaced the 2.5 volt regulator on the t-com board with Digikey 576-3601-5-nd.
The output had been 1.7 volts and the set has been on for over an hour with a good picture.
I also replaced the Capxon power supply capacitors for good measure.
The symptom was fine vertical lines that sometimes filled the screen or at times only in the upper 1/4 of picture. Usually the picture started out ok but worsened but it would also be poor when initially turned on.

Mike

So the output is now 2.5V or 1.7V?

[mu2]

Re: MMC6100B 25 Sub needed

The output is now 2.5 volts.
The bad regulator (2.5 volt) that I replaced had an output of 1.7 volts.
Set has been on for 8 hours now without an issues.

Mike

[tw2005]

Re: MMC6100B 25 Sub needed

Found this forum post,

http://www.plcforum.it/f/topic/14851...5-equivalente/

LD1117S25TR also used and worked as a replacement, output current rated 0.8A