JPS5859236U

JPS5859236U - Analog to digital converter

Info

Publication number: JPS5859236U
Application number: JP15319981U
Authority: JP
Inventors: 美昭田中; 稲見　衛; 大槻　善樹
Original assignee: 日本ビクター株式会社
Priority date: 1981-10-15
Filing date: 1981-10-15
Publication date: 1983-04-21

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of drawings]

第１図は本考案になるアナログ・デジタル変換器の１実
施例の回路図、第２図Ａ−Ｇは第１図示の回路の各部の
信号波形図、第３図は第１図示のコンデンサＣ２の放電
時間と入力レベルとの関係を示す図である。１．５・・・・・・入力端子、２．　３．　４・・・・
・・演算増幅器、６・・・・・・コンピュータ、７・・
・・・・出力端子、Ｃ１゜Ｃ２・・・・・・コンデンサ
、Ｄ□〜Ｄ４・・・・・・ダイオード、Ｑ１〜Ｑ、・・
・・・・ＦＥＴ、　Ｒ□〜Ｒ□２・・・・・・抵抗。Fig. 1 is a circuit diagram of one embodiment of the analog-to-digital converter according to the present invention, Fig. 2 A to G are signal waveform diagrams of various parts of the circuit shown in Fig. 1, and Fig. 3 is a capacitor C2 shown in Fig. 1. FIG. 3 is a diagram showing the relationship between discharge time and input level. 1.5...Input terminal, 2. 3. 4...
...Operation amplifier, 6...Computer, 7...
...output terminal, C1゜C2...capacitor, D□~D4...diode, Q1~Q,...
...FET, R□~R□2...Resistance.

Claims

[Scope of utility model registration request]

Rectify the AC signal to be measured, charge a capacitor with the rectified signal to the peak voltage of the rectified signal, and compare the voltage across the capacitor with first and second reference voltages, while calculating the absolute value of the voltage across the capacitor. is less than the second reference voltage, the capacitor is discharged with a first time constant, and when the voltage is greater than or equal to the second reference voltage, the capacitor is discharged with a second time constant to the second reference voltage. Discharge with the first time constant, count the time from the start of the discharge until the voltage at both ends reaches the first reference voltage, and calculate the digital tide value of the logarithm of the peak voltage of the AC signal under measurement. An analog-to-digital converter configured to obtain