SU549749A1 - Peak Detector - Google Patents

Description

(54) PEAK DETECTOR

This invention relates to electronic measurement technology, in particular, to detecting devices.

A peak detector is known, which contains an on-off amplifier, the inverting input of which is connected to the terminals of the input source through a capacitor and a resistor, & non-inverting input — through a resistor with an input of a smoothing / C-filter, which is connected to the negative feedback circuit of the HFioro audio amplifier and connected to a parallel circuit consisting of a diode connected by a series-connected diode and resistor; however, the diodes are included in antiphase 1.

A disadvantage of the known device is low accuracy. In addition, the use of an oyeracioin amplifier in the signal repeater mode in the region of a linear x 1 detector response diode restricts the diaamic range of the detector to a linear region, the signal of which

1The purpose of the invention is to improve the measurement accuracy and broaden the diaamic range of input voltages.

The proposed nick detector differs in that it introduces an electronic switch and a control key, and the switch output is connected to the input of a smoothing C-filter; One input of the switch is connected to the terminals of the input source} apr, and the other to the output of a controllable key, the input of which is connected to the output of the operational amplifier.

In the drawing, the image of the structure is an electrical circuit of the device.

The peak detector contains a capacitor /, an optics amplifier 2, an electronic switch 3, a control switch 4, resistors 5, 6 H / C-fnlr 7, a state of resistor 8 and a capacitor 9.

The device works as follows. The measured voltage (j through the capacitor 1 and the resistor 5 is fed to the inverting input of the operational amplifier 2 and indirectly to the first input of the switch

3. The output of the switch is connected to the riHTerpnjiyuyushchim / C-filter 7 and through the resistor 6 to the signaling input of the amplifier 2. The second input of the switch 3 is connected to the output of switch 4, which is controlled by the output amplifier of the operational amplifier 2. In the absence of an input signal, eg The output of the amplifier is missing. Nair is also absent at the output of key 4, and switch 3 is closed. In the positive semipergnea input and output / d. At the same time, the output of amplifier 2 is negative, and switch 3 is closed. In the negative half-period, the output voltage of the control system changes, the output of the key 4 appears negative, and the switching NMNULS opens. The voltage Uc on the capacitor 2 increases and over time / 4 reaches the amplitude value U ,,,, After that, the output voltage of the operational amplifier becomes negative, the switch 3 closes and the condiser 9 slowly discharges. In the subsequent negative half-period over time (4), the input voltage LJ exceeds the voltage across the capacitor U,. Formula and 3 about 5 and 5 t Peak detector, containing an operational amplifier, the inverting input of which is connected to the terminals of the input source through a capacitor and a resistor,

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1 f

I ± I and a self-coupling input — through a resistor with a smoothing C-filter input, with a parallel circuit comprised of a diode, a shunty-power diode in series with a diode and a resistor connected in the negative feedback circuit of the amplifier; in order to increase the accuracy of measurements to the extension of the dynamic range of input voltages, an electronic switch and a control key are inserted, with the output of the electronic switch connected with. the input smoothing C-filter; One input of the electronic switch is connected to the terminal of the input voltage source, and the other is connected to the output of the control key, the input of which is connected to the output of the operational amplifier. Information taken into consideration, information for the examination: 1. Shiloh c. l Linear integrated circuits, M., “Soviet Radio, 1974, p. 165.