Hi Guys,
Working on a projects that uses a power supply but has an opamp to filter the power. The current opamp is Lf353 is gets warm when I output 24v+ and 24v- I want to actually do 27+ and 27- but luckily I didnt as I read that the opamp can only take 18+- max! Infact one guy left a feedback on ALiexpress that the chip burnt at 24v!
The capacitors are high enough voltage so is the lm317/6 but the opamp isn't. I don't know anything about high voltage opamp as I've only worked with normal ones like ne5532.
Can anyone recommend a cheap but effective high voltage opamp please? I'm testing with 24v+ and - which is ok but it would be nice to have an opamp that can go a bit higher to. I probably won't ever go past 30v+ and -
Any help appreciated thanks.
This thread seems to have some info and diagnram. I noticed the opamp was getting its power for the ouput terminals of the board. By that I mean if I turn it up to 27v+ and - then the opamp would also get 27v+ and - in its power rails.
Working on a projects that uses a power supply but has an opamp to filter the power. The current opamp is Lf353 is gets warm when I output 24v+ and 24v- I want to actually do 27+ and 27- but luckily I didnt as I read that the opamp can only take 18+- max! Infact one guy left a feedback on ALiexpress that the chip burnt at 24v!
The capacitors are high enough voltage so is the lm317/6 but the opamp isn't. I don't know anything about high voltage opamp as I've only worked with normal ones like ne5532.
Can anyone recommend a cheap but effective high voltage opamp please? I'm testing with 24v+ and - which is ok but it would be nice to have an opamp that can go a bit higher to. I probably won't ever go past 30v+ and -
Any help appreciated thanks.
This thread seems to have some info and diagnram. I noticed the opamp was getting its power for the ouput terminals of the board. By that I mean if I turn it up to 27v+ and - then the opamp would also get 27v+ and - in its power rails.
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Hi,
If you search Mouser, there are several options, most SMD, for higher voltage. E.g. OPA552UA +/-30V
See search - starts from around US$4.00, if you can buy from them in your region or if you have another supplier.
https://www.mouser.com/c/semiconduc...rs-op-amps|~Supply Voltage - Max&sort=pricing
The other option is to build a cheap small PCB discrete opamp with BC639(NPN) and BC640(PNP) to handle up to +/-40V.
Very simple - I can help you to design one if you need.
It will not be perfect in terms of offset, since it's difficult to match the differential pair, nor have a super gain or a super high impedance at the input.
It all depends on your needs.
If you search Mouser, there are several options, most SMD, for higher voltage. E.g. OPA552UA +/-30V
See search - starts from around US$4.00, if you can buy from them in your region or if you have another supplier.
https://www.mouser.com/c/semiconduc...rs-op-amps|~Supply Voltage - Max&sort=pricing
The other option is to build a cheap small PCB discrete opamp with BC639(NPN) and BC640(PNP) to handle up to +/-40V.
Very simple - I can help you to design one if you need.
It will not be perfect in terms of offset, since it's difficult to match the differential pair, nor have a super gain or a super high impedance at the input.
It all depends on your needs.
Hi, I just looked into that unfortunately its single channel, orignal opamp is dual as its + and - rails from one opamp.
I'm not too good with this stuff and I already bought the kit. I much rather just fit the higher voltage opamp which I'm hoping will be 100% problem free. I just tried serching and there is no dual channel OPA552UA.
Any more recommendations? Thanks
I'm not too good with this stuff and I already bought the kit. I much rather just fit the higher voltage opamp which I'm hoping will be 100% problem free. I just tried serching and there is no dual channel OPA552UA.
Any more recommendations? Thanks
The LTC6091 dual opamp is available only in a QFN-16 surface mount package, costs $18.80, and will operate on supply voltages up to +/- 70 volts. Here is its datasheet .
You might be far far better off discarding the existing PCB and laying out a new board yourself, which uses either single opamps (OPA552) or else all-discrete opamp designs made from higher voltage transistors like KSA992 / KSC1845. Both of them are rated for 120V and both sell for less than $0.05 per piece in quantity.
You might be far far better off discarding the existing PCB and laying out a new board yourself, which uses either single opamps (OPA552) or else all-discrete opamp designs made from higher voltage transistors like KSA992 / KSC1845. Both of them are rated for 120V and both sell for less than $0.05 per piece in quantity.
It's not that easy to find cheap dual opamp for high voltage.
The other I see is the ADA4099-2BRZ only that is cheap but handles only +/-25V (50V total).
The other I see is the ADA4099-2BRZ only that is cheap but handles only +/-25V (50V total).
Im not sure but I think this is better ADA4099-2BRZ. It does state 50v max. I'll be running it at 48v. What do you think?
Is this even a good design or should just get a normal lm317/lm337 board? Or should I bypass the opamp?
I copied this fromthe other thread not sure how accurate it is
I copied this fromthe other thread not sure how accurate it is
Yes, it handles 50V rail to rail, or split +/-25V. If you need only 48V, it works according to datasheet.
