Abhinav

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Electrical Engineering

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Abhinav

May 21, 2023 17:43

Any help?

Abhinav

May 21, 2023 17:43

Abhinav

May 21, 2023 03:12

Anyone??

Abhinav

May 20, 2023 17:31

Anyone ?

Abhinav

May 20, 2023 12:00

I gave a request for my profile to be deleted. But its been over the mentioned time and its still not deleted. Any one can help?

Newbie

Mar 24, 2023 13:56

Can someone help me with this question : electronics.stackexchange.com/questions/660064/…

Discussion between Newbie and Tim Wil…

Imported from a comment discussion on electronics.stackexchang...

Newbie

Mar 24, 2023 16:12

So how do we go ahead from there

Newbie

Mar 24, 2023 15:53

Are you there @TimWilliams

Newbie

Mar 24, 2023 15:44

It does not follow from GbE style

Newbie

Mar 24, 2023 15:44

Got mixed up

Newbie

Mar 24, 2023 15:44

Extremely sorry

Newbie

Mar 24, 2023 15:44

sorry

Newbie

Mar 24, 2023 15:42

yes

Newbie

Mar 24, 2023 15:40

Vcc bias from centrerap is there right?

Newbie

Mar 24, 2023 15:35

So the PHY is wired in GbE style

Newbie

Mar 24, 2023 15:32

There is Vcc bias from centretap

Newbie

Mar 24, 2023 15:31

Newbie

Mar 24, 2023 15:30

Yes

Newbie

Mar 24, 2023 15:27

I am sorry if I am not conveying properly

Newbie

Mar 24, 2023 15:27

PHY side centre taps are connected as shown in the page 3 of the checklist document that I shared in the chat link above.

Newbie

Mar 24, 2023 15:24

Could you explain me where I am wrong? Or what I am misunderstanding

Newbie

Mar 24, 2023 15:19

The IC is wired as shown in page 3 of the above document

Newbie

Mar 24, 2023 15:19

ww1.microchip.com/downloads/en/DeviceDoc/…

Newbie

Mar 24, 2023 15:18

right?

Newbie

Mar 24, 2023 15:18

the PHY is not GbE

Newbie

Mar 24, 2023 15:18

Just confused

Newbie

Mar 24, 2023 15:16

Is that TVS part fine?

Newbie

Mar 24, 2023 15:16

@TimWilliams

Newbie

Mar 24, 2023 15:16

@TimWilliams, LAN8740A is the PHY. Also, is the part that I suggested fine?

Newbie

Mar 24, 2023 15:16

@TimWilliams, thank you for your comment. So, you suggest to place the TVS in the location indicated in the app note itself, right? Also, is this TVS Diode OK? semtech.my.salesforce.com/sfc/p/#E0000000JelG/a/2R0000001TBb‌/…

Newbie

Mar 24, 2023 15:16

Am I correct in understanding that it is not correct to move the TVS diode (DBI) from the PHY side of the transformer to the RJ45 side? I feel that it is not right, based on the resistance value and capacitance of the capacitor between the transformer and RJ45 specified in the Hardware Check List @LuC

Newbie

Mar 24, 2023 15:16

@Justme, yes I would need PoE support

Newbie

Mar 24, 2023 15:16

@Kartman, I am trying to protect the PHY chip

Newbie

Mar 24, 2023 15:16

@Justme, could you tell me which position of the ESD would be helpful?

Discussion between Newbie and Andy aka

Imported from a comment discussion on electronics.stackexchang...

Newbie

Mar 24, 2023 10:46

Oh, yes. In the VBAT feed, there seems to be no control.

Newbie

Mar 24, 2023 10:43

Thank you for this clarification. Much appreciate your help

Newbie

Mar 24, 2023 10:42

Thank you. If the output load current increases, the output voltage will drop, right? This is what they might have meant when they said, "The OUT pins do not offer regulation", am I right?

Newbie

Mar 24, 2023 10:36

"For example, if the part has a VREG of 4.2V, the IC charges the battery to Vbat. That is Ok. What about the OUT pins? What would be the voltage at the OUT pins when the input supply IN pin is at 5V? And it is said that the OUT pins do not offer regulation?

Does it mean that the OUT pins would provide the same input 5V and provide 4.2V to VBAT pins? But as per the function diagram, there's a pass MOSFET. How to understand this?

Newbie

Mar 24, 2023 10:36

I asked the below

Newbie

Mar 24, 2023 10:35

In that case, would the input voltage also drop as IN and OUT are connected via a pass MOSFET?

Newbie

Mar 24, 2023 10:35

Is that the meaning of "device not offering regulation" ?

Newbie

Mar 24, 2023 10:34

Yes, I read the section VPCC of the datasheet where VBAT would supply OUT. Incase, I do not have a battery connected, in that case, would the output voltage also drop?

Newbie

Mar 24, 2023 10:34

Would the input voltage also drop?

Newbie

Mar 24, 2023 10:34

As the load current increases on the OUT pin, the output voltage would drop from 5V?

Newbie

Mar 24, 2023 10:33

Newbie

Mar 24, 2023 10:33

This was my question.

Newbie

Mar 24, 2023 10:33

How to understand when one says, that an LDO device does not offer regulation?

Newbie

Mar 24, 2023 10:32

But what they said is that, "The OUT pins do not offer regulation". In general terms, what can we understand when an LDO device states that the OUTput of an LDO does not offer regulation?

Newbie

Mar 24, 2023 10:31

I hence assumed OUT pin would also be 4.2V. But I am not sure.

Newbie

Mar 24, 2023 10:31

I just looked at the internal diagram of the IC and saw that there's a pass MOSFET between the IN and OUT pins.