JPS5554447A - Surface electrometer on negative feedback alternating- current type - Google Patents
Surface electrometer on negative feedback alternating- current typeInfo
- Publication number
- JPS5554447A JPS5554447A JP7491178A JP7491178A JPS5554447A JP S5554447 A JPS5554447 A JP S5554447A JP 7491178 A JP7491178 A JP 7491178A JP 7491178 A JP7491178 A JP 7491178A JP S5554447 A JPS5554447 A JP S5554447A
- Authority
- JP
- Japan
- Prior art keywords
- signal
- voltage
- operational amplifier
- synchronous detection
- converted
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Measurement Of Current Or Voltage (AREA)
Abstract
PURPOSE: To lighten a load on a converting method and also to compose a synchronous detection circuit, etc., of a semiconductor, by sampling and holding a signal from the current-voltage converting method by a signal out of phase by a half cycle synchronizing with cycles of a modulating method.
CONSTITUTION: Electric field Ex generated between measured body 11 and detection electrode 12 by surface potential Vx is changed into flux current Ix by vibrating electrode 10 and then converted into voltage signal by operational amplifier OP1. Although signal V01 is converted into voltage signal V02 by operational amplifier OP2, operational amplifier OP3, capacitor C3 and variable resistance R3 makes an adjustment to a phase needed for synchronous detection, namely, the generation of gate pulses VP1 and VP2 agrees with the bottom of valley of waveforms of voltage signals V03 and V04. Therefore, when pulses VP1 and VP2 are generated, turning switch elements S1 and S2 ON charges capacitor C5 to the peak values of valleys of voltage signals V03 and V04 and the values are stored even if elements are switched OFF, so that synchronous detection output voltage VT can be obtained.
COPYRIGHT: (C)1980,JPO&Japio
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7491178A JPS5554447A (en) | 1978-06-22 | 1978-06-22 | Surface electrometer on negative feedback alternating- current type |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7491178A JPS5554447A (en) | 1978-06-22 | 1978-06-22 | Surface electrometer on negative feedback alternating- current type |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5554447A true JPS5554447A (en) | 1980-04-21 |
Family
ID=13561032
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP7491178A Pending JPS5554447A (en) | 1978-06-22 | 1978-06-22 | Surface electrometer on negative feedback alternating- current type |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5554447A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103616553A (en) * | 2013-12-05 | 2014-03-05 | 上海高试电气科技有限公司 | Short circuit large current waveform fitting method |
-
1978
- 1978-06-22 JP JP7491178A patent/JPS5554447A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103616553A (en) * | 2013-12-05 | 2014-03-05 | 上海高试电气科技有限公司 | Short circuit large current waveform fitting method |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
ES2002958A6 (en) | Method and device for the conversion of an electrical signal into a proportional frequency. | |
JPS5554447A (en) | Surface electrometer on negative feedback alternating- current type | |
JPS5797367A (en) | Converter for converting ac voltage to dc current | |
GB2010032A (en) | Waveform generator | |
JPS5583863A (en) | Amplifier for x ray detector | |
JPH0566235A (en) | Peak holding circuit, peak detecting circuit and peak-position detecting circuit | |
JPS5360675A (en) | Converter for power and dc signal | |
JPS54121177A (en) | Transducer | |
SU962994A1 (en) | Quadratic voltage-to-frequency converter | |
JPS54121025A (en) | Signal generating device for machine operation | |
JPS55166002A (en) | Position detector | |
SU1615754A1 (en) | Square voltage to frequency converter | |
SU752281A2 (en) | Stabilized voltage converter | |
JPS5529722A (en) | Current measuring unit | |
JPS55159109A (en) | Capacity type displacement converter | |
JPS5479417A (en) | Inverter control circuit for motor driveng | |
SU754320A1 (en) | Dc digital voltmeter | |
JPS5483873A (en) | Rotational direction detector | |
JPS5637510A (en) | Displacement converter | |
JPS5467638A (en) | Frequency converter | |
GB953522A (en) | Alternating signal translating circuit | |
JPS5718090A (en) | Charge sensing and amplifying circuit | |
JPS55131783A (en) | Ac contactless potentiometer | |
JPS54134330A (en) | Phase controller | |
JPS54101374A (en) | Peak value detecting circuit of analog signals |