amplifieroperational-amplifiersingle-supply-op-amp
I only have one power supply and I only have the LF353N opamp. Is it possible to design a non-inverting amplifier circuit for this op-amp with only a single power supply?
Otherwise, what are some single power supply op-amp alternatives could I use? I'm using a non-inverting amplifier to amplify a 1V pk-pk 10kHz sine wave to 5V pk-pk.
The microphone's output impedance is irrelevant to the choice of op-amp, because you "program" that aspect by a suitable op-amp circuit.
The low impedance of the mic means that the amplifier can have a low input impedance, in the thousands of ohms. But if the connection from the mic to the amplifier is short (we don't have to worry about stray capacitance of a cable), it doesn't have to. You can build the amplifier to have a relatively high input impedance, like 50 kOhms and up.
If you plan on using a coupling capacitor, like in the recommended circuit, a low input impedance will work against you: a low R means you will need a large C to maintain frequency response, which is linked to the RC product. (Since you give the audible range as 10 Hz (!) to 20 kHz, it can be assumed that you care about low frequency response).
The choice of op-amp depends on various parameters. This is a shopping question that is generally considered off-topic (on most stackexchange sites). You probably want it to be a low-noise unit suitable for audio, which has published distortion figures which are low. Then you have to consider your power supply: would a dual op-amp IC that drains up to 16 mA of current be acceptable? Or how about one that needs a minimum of 10V across its power rails to work properly: would that work? Cost: is it okay if the op-amp costs ten dollars? Or is fifty cents more appropriate? Output: does the op-amp have to produce output that goes almost all the way to the power rails? Or is it okay if it only goes to within a few volts of either rail before clipping? Manufacturing: are you comfortable with small, surface-mounted IC's, or would it be better to have a classic through-hole part with 0.1" pin spacing?
Whether or not a voltage divider is the best approach to power the mic depends on how much wattage will be wasted, and whether you can afford it.
Ahh.. found a few posts here which explains this.
No, it's not using a single supply as per the question linked in your comment, the Maxim circuit is generating a mid-rail - there is an important distinction: -
R1 and R2 bias the non-inverting input at Vcc/2. This sets the inverting input at Vcc/2 and the output of the amplifier also at Vcc/2 when zero photodiode current is flowing.
Basically you can make a single supply TIA with inputs referenced to the most negative rail providing the input current to the TIA is negative i.e. as from a photodiode with the cathode at the input. The photodiode current flows into the cathode and out of the anode and this means the op-amp output will rise above 0V (most negative rail) to re-balance the situation. The re-balance is the output.
Clearly, rail-to-rail op-amps are required for this to work effectively. Take a look at this picture below. It doesn't show power rails but think about the signals. Light generates a photodiode current that flows away from the inverting input. This has to make the output rise higher than the non-inverting input and here lies the basis for a true single-supply, ground referenced TIA. The only caveat is that there will be a small (a few mV) dead-band until sufficient current flows in the photodiode.
Best Answer
Op-amps are not inherently single or dual supply orientated. OK there may be a tiny majority of exceptions that have a "ground" or "0 volt" pin but the vast majority have a positive power pin, a negative power pin, 2 inputs and an output.
The rules are simple: -
So, the LF353A expects to be run from a power rail differential greater than 10 volts and less than 36 volts. If you want to call that +/- 5 volts and +/- 18 volts that's up to you.
The typical input common mode voltage range is typically -12 volts to +15 volts (on a +/- 15 volt supply) and this translates to +3 volts to +30 volts on a single ended +30 volt supply
OR
+3 volts to +20 volts on a single +20 volt supply.
However, the data sheet only guarantees +/- 11 volts on a +/- 15 volt supply so if you don't want to take risks this translates to +4 volts to + 26 volts on a single +30 volt supply.
There are graphs in the data sheet that give more detail such as figure 6 and 7.
There are also specifications and graphs for output voltage swing.
In short >99% of all op-amps do not understand there power supply regime - they are only interested in the differential supply voltage being within workable limits.