Browse Prior Art Database

Analog Measurements and Identification From a Serial String of Sensors

IP.com Disclosure Number: IPCOM000081010D
Original Publication Date: 1974-Mar-01
Included in the Prior Art Database: 2005-Feb-27
Document File: 2 page(s) / 58K

Publishing Venue

IBM

Related People

Prentice, PN: AUTHOR

Abstract

The arrangement shows how to obtain analog information contained in a serially wired string of sensors.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 66% of the total text.

Page 1 of 2

Analog Measurements and Identification From a Serial String of Sensors

The arrangement shows how to obtain analog information contained in a serially wired string of sensors.

A serial chain of sensors 10 through 10n is shown in Fig. 1. The details of this string of sensors is shown in Fig. 2. Assume that each storage flip-flop 12 in the string of sensors contains a logical 0. A single 1 is introduced into the first sensor. This 1 will be propagated from sensor-to-sensor under control of the clock pulse, such that there is only a single 1 in the string of sensors at a time. When the 1 issues from the last sensor 10n+1, it resets the counter 14 and reprimes the first sensor via line 16. The same clock pulse that advances the logical 1, steps the counter 14 such that the count always reflects the current address of the logical 1 in the string of sensors.

The clock-ramp line 20 has impressed thereon a composite waveform 22 consisting of two parts: a negative-going clock, and a positive ramp. The clock is used to serially step the 1 value through the sensors, as previously mentioned. The ramp is impressed on one side of a differential amplifier 24, which has a voltage representing the value of an analog sensor such as a thermistor 26 registered on the other side. When the two voltages are equal (difference 0), the crossing is detected and this signal is propagated over the interrupt line 28, if gated by the on condition of the flip-flop 12. This causes the value of th...