Author Topic: how to understand the functionality of circuit  (Read 4574 times)

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audio

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Re: how to understand the functionality of circuit
« Reply #50 on: February 06, 2022, 08:27:48 am »
Sir,
Is there any way to include current limit indicator circuit. PFA.

xavier60

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Re: how to understand the functionality of circuit
« Reply #51 on: February 06, 2022, 11:05:45 am »
One way is to use another BJT to sense the voltage between pins 2 and 3 with a resistor in series with the Base. The best resistor value might need to be found by testing. A 1K to start with.
The indication can never be trusted to be precise.

I guess it wouldn't hurt to drive an LED with a few mA using the REF pin as the supply.
« Last Edit: February 06, 2022, 11:08:51 am by xavier60 »
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xavier60

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Re: how to understand the functionality of circuit
« Reply #52 on: February 06, 2022, 11:18:03 am »
There is a chance that the indicator BJT might never turn on enough. To fix it, a high value resistor might need to be connected from the REF pin to the Base of the indicator BJT.
Hioki AS100D vom, HP 54645A dso, Fluke 87V dmm, AN8008 dmm, Agilent U8002A psu,  FY6600 function gen, New! Brymen BM857S-(With Battery)

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audio

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Re: how to understand the functionality of circuit
« Reply #53 on: March 03, 2022, 04:38:03 pm »
Hi to all,

How this circuit is having control on Current?

R11 should be 240ohm or 120 ohm but in the circuit it is 4.7K. does this affect the q current of regulator.

what is the function of T1,T2,T3,D8,D9 in current regulation???
« Last Edit: March 03, 2022, 05:26:50 pm by audio »

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