The AD623 is a single chip instrumentation amplifier. The internal circuit is based on a modified classic three op amp approach to assure single or dual supply operation even at common-mode voltages at the negative supply rail. Some key features are: Low voltage offsets, input and output, as well as absolute gain accuracy, and one [...]
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Implementing peak-detector circuits is very easy with the CA3130, as shown in schematic diagram of this circuit. The figure below shows the schematic diagram of the peak detector circuit. The upper section is peak-positive and the lower section is peak-negative circuit.
Please note that with large-signal inputs, the bandwidth of the peak-negative circuit is much less [...]
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The schematic diagram below describe a precise full-wave rectifier circuit. The circuit needs only a single supply, make it suitable for battery operated devices.
During the positive cycle of the input, the signal is directly fed through the feedback network to the output, give the transfer function of Vout=R3/(R1+R2+R3). At the positive cycle of the input, [...]
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The schematic diagram below shows a very simple sample-and-hold circuit using the CA3140 as the readout amplifier for the memory capacitor. The CA3080A is used as both input buffer amplifier and low feed-through transmission switch. System offset nulling is provided for CA3140 via its offset nulling pins. A load simulation of 2k and 30pF is [...]
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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 [...]
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