[sergey23 0]

Hello, I was given the following circuit, somehow its suppose to delay  one DC voltage after the other DC.
I suppose its opening Vd+ later then the others.The inputs are totally DC.
Somehow there is RC mechanism which will delays the opening of maybe Q1.
Probably I am totally wrong but this this what its supposed to do.
Is there some more practical intuitions regarding how this circuit works?

If this circuit is tottaly wrong,maybe a similar circuit which I could try and simulate?
Thanks.

[_Sergey_ 16]

q1, q2, and q3 don't allow Vd+ appears before net -12v falls to -10V and lower.

The schematic doesn't contain any RC mechanism which controls DC outputs.

Add:

More exactly, q1, q2, q3 don't allow Vd+ voltage rise faster than -12V voltage falls.

R11/R12 divider provides proportional rise Vd+ relatively -12V changes.

R? provides positive feedback for threshold.

[sergey23 0]

Hello Sergey , Is there a way you reccomend to change this circuit so it will output one DC signal after the other?

Thanks.

Изменено 28 августа пользователем sergey23

[_Sergey_ 16]

How much time do you need to delay?

[_Sergey_ 16]

Maybe the answer of your questions is absent junction of R12 with net -12V?

[sergey23 0]

Hello, I was told the following, I need to increase garually one of the inputs to see the effect.
my load TGA2227 photos of the sequences needed shown in the photos.
My inputs are +12 -12 GND What input shouldI increase gradually?
Could you say the logic of the different part so I could understand the inner workings logic?
Thanks.

" if the voltage rises slowly, the outputs will switch in sequence. Try a simulation and slowly increase the input voltage to see how the outputs changes."
"in MOS amplifiers to ensure the gate voltage is present before the drain voltage or vice versa, depending on the design so the device can't start up at maximum current if voltage on the gate isn't present first"

 

[sergey23 0]

Hello ,After working on this I came to the conclusion that this circuit is just checks the sequence.
Its not creating the sequence its just checking that the sequence is  correct.
This circuit is very faulty so Just need analog logic to build a new one.
Suppose first create a lower edge  0 to -2.5V to the gate  and then a rising pulse  0 to +8V to the drain as shown below.
Suppose I have +12V -12V rails and I put a delay between them.
BJT's are  Valves  ,What is the BJT logic to make it function as a sequence checker? 
Thanks.

 

[Plain 212]

В 28.08.2024 в 22:45, sergey23 сказал:

TGA2227 ... sequences needed

[sergey23 0]

Hello Plain, Could you please give an intuition regarding the following:

1. Why do we have two inputs Vg_on and Vg_Dac?

2. What is the general logic of this circuit?
Thanks.
 

[Plain 212]

38 минут назад, sergey23 сказал:

1. Why do we have ... inputs Vg_on ... ?

39 минут назад, sergey23 сказал:

1. Why do we have ... inputs ... Vg_Dac?

41 минуту назад, sergey23 сказал:

2. What is the general logic of this circuit?

With any small MCU you like (PIC16F1823, MSP430FR2000, STM8S003, etc.) you create by MCU outputs a sequence of xx_ON signals, then with any DAC you like (AD5601, MCP4911, etc.) connected to this MCU you create on DAC output (VG_DAC) an linear increasing voltage until you receive on MCU input a signal I_lim (i.e. Ids=125 mA, datasheet nominal value in table above), then you create by MCU output turn on signal for "RF switch" IC/circuit (item "5." in table above). Switching off is done in reverse order.

The circuit can be switched on/off by this MCU an external control signal, provided that all supply voltages is not lower than the nominal values (controlled by built-in MCU ADC inputs).

[_Sergey_ 16]

22 hours ago, Plain said:

The circuit can be switched on/off by this MCU..

The modern uC utilizes a mosfet technology. But topicstarter was told to use BJTs only.

🙃

[Plain 212]

Vintage BJT only sequencer:

[sergey23 0]

Hello Plain, very intersting circuit.
Could you give intuition regarding  parts of this circuit so i could simulate them apart and see how they work individually?
Thanks.

Изменено 20 сентября пользователем sergey23

[iddqd2001 2]

Да простят меня уважаемые модераторы, но я не понимаю, почему пользователю под ником sergey23 дозволено спамить в теме "Вопросы аналоговой техники", полностью копируя туда рандомные, вырванные из контекста посты с форумов EEVBlog и edaboard. Такое впечатление, что кто-то просто обкатывает чат-бота.

[sergey23 0]

Hello, I get here more help then in other forums.

Its not spamming i am really trying to learn.