Free Circuit Diagram

To produce a pre-amplifier with accurate RIAA response, this circuit use two stages of amplifier. This circuit is more complex than single op-amp RIAA pre-amp, but the performance is excellent in terms of accurate frequency response. Here is the schematic diagram of the circuit.

The circuit uses LM833 high performance op-amp from National Semiconductor, giving the [...]

Recording Industry Association of Ameria (RIAA) has developed the recording standard of response curve for their recording. This curve is developed to optimize the gramophone recording response for lowest signal-to-noise ratio for gramophone technology. Because the tape recording response is not linear, the pre-amp for gramophone playback pickup should have such  response that restore the [...]

Current amplifier application need very low input bias current, and CA3140 is one of suitable op-amps for this purpose. The circuit’s schematic diagram is shown in the figure below.

In the circuit, low current is supplied at the input potential as the power supply to load resistor RL. When the load current is monitored by the [...]

Here is a schematic diagram of electret microphone pre-amplifier using LMV721 op-amp. because the LMV721 has low noise and low power features, it would be an ideal choice for  battery powered microphone preamplifier. The LMV721 is connected as an inverting amplifier.

Resistors, R1 =R2 = 4.7k, sets the reference at mid point between VCC = 3V [...]

Balanced input has three connections, ground, positive signal, and negative signal. When we trace the signal using oscilloscope, if we take the ground as the reference, then the negative signal and the positive signal has similar shape but with inverted polarity. If we measure the signal between positive and negative output, the we have two [...]