[SOLVED] Op-Amp Positive Supply drops down..........

[SACHIN C]

Kam1787,
Trancation means limiting digits or signal value up to certain level & then above which it will not pass but,in our case while observing signal on CRO Op-Amp Signal displays lifted by 3.58V with respect to ground(which is center tapped point of the transformer).
So shall i need to change resistor ground at input of Op-Amp,as shown in above attached file?
XR2206 Supply Connection is +15V & ground so it is the stage where the signal is lifted?

Thanks,:smile:

 

[kam1787]

Kam1787,
Trancation means limiting digits or signal value up to certain level & then above which it will not pass

Your definition is faulty. I DO know what truncation is and I can even spell it.

 

[SACHIN C]

kam1787,
That was typing mistake but i mean to say Truncation.
Can you please explain me the technical aspect of Op-Amp Output signal been truncated,as from technical term point of view i don't know the meaning?

Thanks,:smile:

 

[SACHIN C]

Dear All,
Thanks 2 all of u:smile:
i got the problem which was related to Op-Amp positive feedback Summing Op-Amp as the corrected signal was again feed to Non-Inverting Terminal as per diagram which was driving Summing Output to Positive Saturation.
So i now modified the circuit and use Inverting Terminal as a feedback which maintain changes of open loop.:smile:

Thanks,:smile::smile:

 

[SACHIN C]

Dear All,
what to do with unused three opamp form TL074 of which single Opamp is being used as an comparator?
Positive Supply : +15V
Negative Supply : -15V


Thanks & waiting for knowledge enhancement,:smile:

 

[FvM]

My personal preference is wiring each unused FET OP as unity gain buffer with non-inverting input connected to circuit ground.

 

[SACHIN C]

FvM,
Non-Inverting Pin to ground,Inverting pin to output pin of opamp,but output pin of opamp will be remain unconnect?
How to connect remaining,



Thanks & waiting for knowledge enhancement,:smile:

 

[SACHIN C]

FvM,
I connected unused Op-Amp as unity gain(Post No :26,27) but,still 7915 & TL074 is getting heat up?



Thanks & waiting for knowledge enhancement,:smile:

 

[SACHIN C]

Dear All,
As i mention earlier i have being using TL074 Quad Op-Amp stages wise as mention below,
1-Difference Op-Amp
2-Inverting Op-Amp Gain 0.1(Attunator)
3-Summing Non-Inverting Op-Amp
4-Comparator for Sinewave & Triangular wave as an input,
But comparator output is not responding fast as tr=0.1us mention in datasheet?

Can Tl074 be use as an comparator?

Op-Amp Supply=+-15V,
Sinewave=2.5Vpeak
Triangular Wave=3Vpeak
Carrier Frequency =10KHz,
Comparator Output =+-15 which is max will it create problem?

What will be the alternate good option for comparator?

Thanks & waiting for knowledge enhancement,:smile:

 

[FvM]

4-Comparator for Sinewave & Triangular wave as an input,
But comparator output is not responding fast as tr=0.1us mention in datasheet?

I fear your datasheet literature is rather randomly. I guess you are referring to the small signal rise time specification, shown for a 20 mV voltage step. For large signal, the slew-rate specification will dominate the rise time. You can expect about 2 µs for +/- 15V supply.

 

[SACHIN C]

FvM,
can you suggest me some Comparator because i also need high slew rate around 20V/us,
i selected below Op-Amp can you guide me which is proper,
OPA354
LM311N
OPA2365


How calculated 2us?
Practicaly i observed Comparator output (TL074) shows 8us change of state time which miss many instances,it is not fast reacting?

Can 10KHz & 50Hz Signal as an input for comparator creates problem because of different frequency,shall i need to have ac capacitor?

I have another dought if +Vsat=5V & -Vsat=0V Grounded,for comparator & Sinewave=2.5Vpeak,Triangular=3Vpeak are given as an input then can comparator work?

Thanks & waiting for knowledge enhancement,

- - - Updated - - -

k i got i think so 8V/us means for 15V it will be 2us,is it ?

 

[FvM]

You should use a dedicated comparator when you want high slew rate and fast reaction. LM311 is an old but still suitable devive. It's output stage is different from a standard OP, refer to the datasheet suggestions how to use it.

I don't know where you see 8 µs delay with TL074, but you didn't show the actual circuit, isn't it? If TL74 is supplied with +/15 V, the output swing is about 30V however.

 

[SACHIN C]

FvM,
I got LM339 which is quad Comparator & i am getting the proper response at the output of Comparator,but what to do with remaining three internal comparator as i am going to use only single comparator from quad?
I searched online many people are suggesting to ground the both inputs of remaining Comparator,will it works?
As for LM311 i was confused with strobe & balance pin,didn't know where to connect the pin?

thanks & waiting for knowledge enhancement,