Free Circuit Diagram

The excellent high input impedance, high slew rate, and high voltage qualities of CA3140 op-amp make it suitable for Wien-bridge sine wave oscillator. The basic circuit for Wien-bridge sine wave oscillator is shown in the figure below (the upper part). You can see the formula in the figure, when R1=R2=R, and C1=C2=C, then the formula [...]

This circuit is similar to our previous tone control circuit, a bass-treble tone control circuit, but here we present the formula for design your tone control’s custom frequency response. Here is the schematic diagram and formula of the tone control circuit: Almost all op-amp type can be used, as long as they have [...]

For standard instrumentation amplifier, a three op-amps instrumentation amplifier circuit is common, but if you need smaller component count and lower cost, you can use just two op-amps for the same function: a high impedance and good CMRR for sensor pre-amplification and buffering. Here is the circuit’s schematic duiagram: A two-op-amp instrumentation amplifier [...]

The simple low-pass filter is shown in Figure below. The filter has a 20dB/decade roll-off after its corner frequency fc. Its low-pass frequency gain (f->0) is defined by R3/R1. This allows low-frequency gains other than unity to be obtained.  R2 should be chosen equal to the parallel combination of R1 and R3 to minimize error [...]

Using LMV721/722 or any other high impedance op-amps, you can build an instrumentation amplifier using standard three op-amps instrumentation amplifier circuit. The figure below shows the circuit’s schematic diagram. The final stage of this instrumentation amplifier is a differential-input, differential-output amplifier, with two voltage followers feed its inputs. These two voltage followers assure [...]

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 [...]