Hi all!
Does anyone has made amplifiers under this schematic?
Is this is a good schematic (circuit) and should make some changes for the power supply for the Ucc=+/-40V?
Is this Schematic-N is better?😉😕
Thank you for your cooperation!
Does anyone has made amplifiers under this schematic?
Is this is a good schematic (circuit) and should make some changes for the power supply for the Ucc=+/-40V?
Is this Schematic-N is better?😉😕
Thank you for your cooperation!
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One cannot power an opamp rated for 15v from 37v,explosion will be instant,but you can try lowering the the rails to 15v and try it so,it is a very common topology in amplifiers
The 2nd schematic looks more promising, but the 3055 is not able to handle the +/-40V supply.
Generally it's very simple, and well known topology.
Sajti
Generally it's very simple, and well known topology.
Sajti
cant vouch for the rest of the circuit, but I can say that with the supply to the opamp regulated as shown, its not going to explode at all, and if the zener is suitably rated the 2k resistor is fine. Ohms law if you want proof, but 25 volts across a 2k resistor is going to generate around 1/3 of a watt of heat. Smoke is an unlikely result.
According to the datasheet the 741 is internally compensated for unity-gain and pin 8 is not connected. So the 10pF capacitor is useless.
Its slew-rate is also on the low side (0,5 - 0,7V/µs). This gives an over-all slew-rate of max. 5V/µs. A NE5534 (with those 10pF or more) will give better results.
The second schematic should have better thermal stability but the component values of the bias-spreader are not correct (BD689 is a Darlington, VR1 should be placed in the B-E branch).
Its slew-rate is also on the low side (0,5 - 0,7V/µs). This gives an over-all slew-rate of max. 5V/µs. A NE5534 (with those 10pF or more) will give better results.
The second schematic should have better thermal stability but the component values of the bias-spreader are not correct (BD689 is a Darlington, VR1 should be placed in the B-E branch).
Is it possible BD679 can be replaced with BD139 and IC LM741 be replaced with a TL071?😕🙁
This schematic-NEW gave it right?
thanks!
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Since the output stage is a feedback pair (common emitter) then the op amp is not responsible for the voltage gain. A lower voltage source for the op amp is required and will not affect the limit of the output voltage swing. Sure the resistor's current drops out the voltage but at the instant of power up, destructive voltage could possibly occur across the op amp. It is just good practice and good for reliability in electronics that devices, especially BJTs are not subject to Vceo breakdown voltages as it reduces the life expectancy significantly.🙂
Hello guys!
Such means should be amplifier!!😉😱
Or something should be changed for the better?!
cheers!
Such means should be amplifier!!😉😱
Or something should be changed for the better?!
cheers!
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Here is a link to the one that I made a while back,
http://www.diyaudio.com/forums/chip...own-supply-what-could-happen.html#post3695968
It worked good.
I will be using a ADA4700-1 high voltage opamp on the next version in order to get more voltage swing out of it.
http://www.analog.com/static/imported-files/data_sheets/ADA4700-1.pdf
jer 🙂
http://www.diyaudio.com/forums/chip...own-supply-what-could-happen.html#post3695968
It worked good.
I will be using a ADA4700-1 high voltage opamp on the next version in order to get more voltage swing out of it.
http://www.analog.com/static/imported-files/data_sheets/ADA4700-1.pdf
jer 🙂
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