SU1332240A1 - Peak voltage detector - Google Patents

Abstract

The invention relates to computing and measuring technology. The purpose of the invention is to increase the speed and accuracy of fixing and storing peak voltage values. The peak detector contains comparators 3 and 4, a bias voltage source 1, an adder, and a switchable source. ka, current switch, charging diode 7, storage capacitor 8, voltage follower 12, bit switches 9 and 10, current-setting resistor 11. Storage capacitor is charged to the value of the input voltage from a switched current source. The charging process is controlled by comparators. To eliminate a leak, the discharge circuit consists of two bit switches and a resistor. An embodiment of a switchable current source is presented. 2 Il. in (L

Description

 13

The invention relates to computing and measuring technology and can be used in various information and control systems.

The purpose of the invention is to increase the speed and accuracy of fixing and storing peak voltage values.

FIG. 1 shows a scheme of a pikh detector; FIG. 2 shows a circuit of a switched current source, an option.

Peak detector contains bias voltage source 1, adder 2, first and second comparators 3 and 4, switchable current source 5, current switch 6, charge diode 7, storage capacitor 8 and first and second discharge switches 9 and 10, current switches a resistor 11, a voltage follower 12, an input 13, an output 14, a reset control input 15. Switchable current source 5 contains transistors 16-18, separation diodes 19-22 and current-supplying resistors 23-28.

The device works as follows.

When the input signal rises, the peak detector operates in tracking mode. In this case, the voltage on the storage capacitor 8 increases due to the charge of its current by the switched current source 5. When the input and output signals are equal, the comparator 3 is triggered, the current switch 6 is closed, the diode 7 is closed and the device goes into storage mode until the input voltage is greater than the output voltage. The speed of the circuit is determined by the value of the output current of the switching current source 5, which is selected from the condition:

 "X

where 1 - switchable output current

current source 5; C is the storage capacity of the con. 8j, a and I.V h C--) - the maximum speed is measured by m not

no input signal.

The delay of the operation of the comparator 3, the current key 6 and the delay of the repeater 12 leads to an error in fixing the peak value of the input signal

di

1 l t. WITH

where lt is the total delay time

power off. To reduce this log resolution, a comparator 4 is used, the characteristic of which is shifted by the source and cim ia toopa 2 by the value of and (.cd somewhat larger than it. Therefore, the comparator 4 is triggered when and -1 Up (x P is the current source 5, switches from a current of magnitude 1 to a current of magnitude 1. The dosage of the storage capacitor 8 with a smaller current provides a reduction in the peak fixation error. The magnitude 1 | is determined by the relation-;

t 2-4t.

where is the tolerance

fixing the peak value of the input signal. In re; sim storage change for example. The capacitor 8 is caused by leakage currents of the bit switch 9, which are determined by the voltage drop between its input and output. The introduction of the resistor 11 and the second bit switch 10 reduces the voltage drop on the key 9 in the storage mode to a value close to zero and virtually eliminates leakage currents.

The magnitudes of the currents I, and 1 are determined with the emitter resistors 22 and 27. The current is turned off using a transistor switch on the transistor 18.

formula of invention

A peak voltage detector, containing a memory capacitor, is connected between the voltage follower input and the potential zero potential, the first bit switch, the control input which is the detector control output of the detector, and the first signal connected to the secondary input and the charge cathode the diode, the output of the voltage follower is annihilated by the output of the detector, characterized in that, in order to increase the speed and accuracy of fixing and storing peak voltage values, it further comprises

two comparators, a second bit switch, a bias voltage source, an adder, a current-carrying resistor, a switchable current source and a current switch connected between the zero potential bus and the output of a switchable current source connected to the anode of the charge diode, the peak detector input is connected to the first inputs the adder and the first comparator, the second input of which is connected to the output of the voltage follower and to the first input of the second comparator, and the output to the control input of the current switch.

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24

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Compiled by G. Osipov Editor A. Vorovich Tehred M, Khodanich Proofreader V. Girn

Order 3828/41 Edition 730 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

240

the output of the bias voltage source is connected to the second input of the adder, the output of which is connected to the second input of the second comparator, the output of which is connected to the control input of the switchable current source, the second output of the first bit switch is connected via a current-supply resistor to the output of the voltage follower, and after the second dny key - with a zero potential bus, the control inputs of the first and second bit keys are combined.

13 21 27

 20

22

G7

25

"

Claims (1)

Claim A peak voltage detector containing a storage capacitor connected between the input of the voltage follower and the zero potential bus, the first bit key, the control input of which is the reset control input of the detector, and the first output is connected to the input of the follower and to the cathode of the charging diode, the output of the voltage follower is the output of the detector , characterized in that, in order to increase the speed and accuracy of fixing and storage of peak voltage values, it further comprises S two comparators, a second discharge key, a bias voltage source adder, a current-setting resistor, a switched current source and a current switch connected between the zero potential bus and the switched current source output connected to the anode of the charging diode, the peak detector input is connected to the first inputs of the adder and the first a comparator, the second input of which is connected to the output of the voltage follower and to the first input of the second comparator, and the output with the control input of the current switch, the output of the bias voltage source connected to the second input of the adder, the output of which is connected to the second input of the second comparator, the output of which is connected to the control input of the switched current source, the second output of the first discharge key is connected through the current-supply resistor to the output of the voltage follower, and through the second discharge key to the bus of zero potential, the control inputs of the first and second bit keys are combined15.