An opamp is a super high gain amplifier. So amplify the difference between your input and a reference. Your NTE928M won't be able to pull the output up to 5V unless you give it about 7V Vcc. A better way would be to use a comparator with an open collector output. Google for comparator. Also google for 'hysteresis'.
I'm not an experienced electronics person, and so have a "stupid question". I have a device that provides an "on" signal intermittently at 2.7 volts DC.
When the "on" of 2.7 volts is available, I need to have a "sub-circuit" receive an "on" of 5.0 volts. I have a source of 5.0 volts on the board. I've been told I need to use an op amp to do this, so I bought two NTE 928M op amps. I've tried to get this to perform as I need, but can't. HELP please!!! I put resistors in somewhere, but where and how big? tanksalot S.F.
Post the circuit you are using. And give us information on the circuit you are feeding the +5 volts to. How much current does that circuit draw from the % volt "on" ?
The NTE 928 can't provide 5V output with a supply of only
5 volts. It won't do what you want directly, but first things first - get it working. Once you get the NTE 928 working, we can get into the necessary additional circuitry.Or we can give you a circuit that does not use the NTE 928M, but that will work properly.
By the way NTE parts cost more, so it's a good idea to look beyond NTE for your parts in the future.
Ed
You could do it with a couple transistors and resistors, but it's difficult to describe.
How much current is availiable from the 2.7 source, and how much current is required by the 5 volt "sub-circuit" ?
-Bill
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