# US 6,297,673 B1 · Evaluation circuit for electronic signal transmitters

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 6,297,673 B1
- Document ID: US6297673B1
- Status: Granted
- Kind: B1
- Application number: 09/423,989
- Filed: 1999-11-17
- Granted: 2001-10-02
- Earliest claimed: 1998-03-21
- Assignees: Robert Bosch GmbH
- Inventors: Michael Walther
- Web page: https://patentgrep.com/patent/US6297673B1

## CPC

- G01P 3/489: Digital circuits therefor
- B60T 8/171: Detecting parameters used in the regulation; Measuring values used in the regulation
- G01D 5/14: influencing the magnitude of a current or voltage
- G05F 3/262: {using field-effect transistors only}
- G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G})
- B60T: VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL (electrodynamic brake systems for vehicle, in general B60L; brakes per se, i.e. devices where braking effect occurs, including ultimate brake actuators, F16D); ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G05F: SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES

## Abstract

The evaluation circuit has a current interface (1,1′; 11,11′) for a current signal (i2) from an electronic signal transducer (6,6′; 16,16′); a current-sensing FET (3,3′; 13,13′) having a gate (G), a source (S), a drain (D) and a sensing output (sense), which is connected so that the current signal from the transducer passes through the source and drain; a monitoring circuit (5,5′; 15,15′) for controlling the current-sensing FET in the event of a malfunction connected between the gate (G) and to the drain (D) or source (S); a current reflector circuit (4,4′; 14,14′) having an input connected to the sensing output (sense) of the current-sensing FET and a resistor (2,2′; 12,12′) for converting current to voltage, which is connected to an output of the current reflector circuit, so that the current signal is converted to a voltage signal tapped between the resistor and the current reflector circuit.

## Claims

### Claim 1

An evaluation circuit for an electronic signal transducer (6,6′), said evaluation circuit comprising
a current interface (1;1′; 11,11′) for supplying a current signal (i2) from the electronic signal transducer (6,6′);
a current-sensing field effect transistor (3,3′; 13,13′) having a gate (G), a source (S), a drain (D) and a sensing output (sense), said current-sensing field effect transistor being connected with said current interface (1,1′; 11,11′) so that said current signal (i2) supplied by said transducer (6,6′) passes through said source (S) and said drain (D);
monitoring circuit means (5,5′; 15,15′) for controlling said currrent-sensing field effect transistor (3,3′; 13,13′) in the event of erroneous operation or malfunction, said monitoring circuit means having an output terminal connected to said gate (G) of said current-sensing field effect transistor (3,3′; 13,13′) and an input terminal connected to said drain (D) or said source (S) of said current-sensing field effect transistor (3,3′; 13,13′);
a current reflector circuit (4,4′; 14,14′) having an input and an output, wherein said input of said current reflector circuit is connected to said sensing output (sense) of said current-sensing field effect transistor (3,3′; 13,13′); and
means (2,2′) for converting current to voltage, said means for converting being connected to said output of said current reflector circuit (4,4′; 14,14′), so that said current signal (i2) is converted to a voltage signal (Us).

### Claim 2 (depends on 1)

The evaluation circuit as defined in claim 1, wherein said means (2,2′) for converting current to voltage comprises a resistor.

### Claim 3 (depends on 1, 2)

The evaluation circuit as defined in claim 1 or 2, wherein said input terminal of said monitoring circuit means (5,5′) is connected to said drain (D) of said current-sensing field effect transistor between said drain (D) and said current interface (1;1′).

### Claim 4 (depends on 1, 2)

The evaluation circuit as defined in claim 1 or 2, wherein said input terminal of said monitoring circuit means (15,15′) is connected to said source (S) of said current-sensing field effect transistor between said source (S) and said current interface (11,11′).