Title:
DEVICE FOR OBTAINING ANALOG DATA
Document Type and Number:
Japanese Patent JPS5387648
Kind Code:
A
Abstract:
An improved interface circuit for use between variable voltage analog sensors which are measuring physical parameters and a microprocessor which is processing the data relating to such parameters. The interface unit is of the type employing an analog multiplexer, an analog to digital converter, a voltage to frequency converter, a counter for converting frequency to digital data, and a bus adapter for connection to the microprocessor. The inventive improvement relates to providing the multiplexer as a differential multiplexer having two differential voltage outputs and having a sign detector connected thereto. A switching block is connected between the differential voltage outputs and the voltage to frequency converter and also to the sign detector thereby acting as a selector circuit. The selector circuit passes each voltage output signal of the multiplexer which has a constant sign to the voltage to frequency converter, wherein the counter is an up/down counter whose counting input is connected to the sign detector output.
Inventors:
KUROODO REIKUREI
Application Number:
JP93478A
Publication Date:
August 02, 1978
Filing Date:
January 10, 1978
Export Citation:
Assignee:
RENAULT
International Classes:
H03M1/60; F02D41/24; F02P5/15; G06F3/05; G06F19/00; G06J1/00; H03M1/00; (IPC1-7): G06F3/05; G06J1/00
Domestic Patent References:
| JPS4831136A | 1973-04-24 |