
Autoranging is useful to extend the measurement range of an available ADC (analog-to-digital converter). Autoranging will best implemented for multiplexed input. LTC1257 is appropriate for system autoranging, adjusting an ADC’s full-scale range. During the conversion process, U2 and U3 receive the full and zero scale codes, respectively, that correspond to a [...]
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Using a single supply quad comparator LM339, LM239, LM2901, LM2901V, NCV2901, or MC3302, we can build a square-wave oscillator with simple circuit and formula. Here is the schematic diagram: This circuit is suitable if you need many square-wave oscillators in one circuit, since the quad packaged comparator provide four comparators in one single [...]
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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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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 [...]
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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 [...]
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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 [...]
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