Sensor chip

Patent metadata

Field	Value
Publication number	US-10718639-B2
Application number	US-201514809429-A
Country	US
Kind code	B2
Filing date	Jul 27, 2015
Priority date	Jul 29, 2014
Publication date	Jul 21, 2020
Grant date	Jul 21, 2020

Abstract

A sensor chip comprises a sensing element providing a sensor signal, an on-chip memory, a configuration of a look up table of dimension N stored in the on-chip memory for assigning an output value to a combination of N input values, and a look up table engine for determining a corresponding output value in response to receiving a memory address for the look up table configuration and in response to receiving a sensor value derived from the sensor signal as one of the N input values.

First claim

The invention claimed is:

1. Sensor chip, comprising
a sensing element providing a sensor signal,
an on-chip memory,
a configuration of a look up table of dimension N stored in the on-chip memory for assigning an output value to a combination of N input values,
a look up table engine for determining a corresponding output value in response to receiving a memory address for the look up table configuration and in response to receiving a sensor value derived from the sensor signal as one of the N input values,
a system controller configured to copy the memory address and the sensor value as one of the N input values to the look up table engine for generating the corresponding output value,
wherein the look up table engine is implemented as hardware,
different configurations of look up tables of dimension N stored in the on-chip memory each for assigning an output value to a combination of N input values,
wherein the system controller is configured to call the different look up tables in sequence,
wherein calling different look up tables is stored in form of a micro-program in the on-chip memory, and is executed by the system controller.

2. Sensor chip according to claim 1 ,
wherein an output value of a first of the look up table configurations represents an input value to a second of the look up table configurations.

3. Sensor chip according to claim 1 ,
wherein a program that makes the different look up table configurations be called in sequence when being interpreted by the system controller is stored in the on-chip memory, and
in particular wherein the program is a micro program.

4. Sensor chip according to claim 1 ,
wherein the on-chip memory is a one-time programmable on-chip memory.

5. Sensor chip according to claim 1 ,
wherein the or each look up table configuration includes a look up table header comprising information with respect to a number of sampling points for each dimension N, a sampling point representing an input value in the corresponding dimension for which input value an output value is stored in the look up table configuration for each sampling point of any of the other dimensions, and
in particular wherein the information with respect to the number of sampling points comprises a number of sampling point intervals between the sampling points in the corresponding dimension.

6. Sensor chip according to claim 5
wherein the or each look up table header includes information referring to an interpolation to be applied per dimension for determining an output value for an input value in this dimension that does not match any one of the sampling points, and
in particular wherein the information referring to the interpolation includes an order of interpolation to be applied.

7. Sensor chip according to claim 1 ,
wherein N=2 for each look up table configuration, and
wherein a look up table configuration of a single dimension is implemented by setting the information with respect to the number of sampling points for the other dimension to zero.

8. Sensor chip according to claim 1 ,
wherein the or each look up table configuration indicates an interval size between two adjacent sampling points for each dimension N.

9. Sensor chip according to claim 1 ,
wherein the or each look up table configuration includes an output value for each combination of sampling points of the various dimensions.

10. Sensor chip according to claim 1 , comprising
an analogue to digital converter for converting the sensor signal from an analogue form into a series of sensor values in digital form,
a register for temporarily storing the sensor values.

11. Sensor chip according to claim 1 , comprising
another sensing element providing another sensor signal,
another analogue to digital converter for converting the other sensor signal from an analogue form into a series of other sensor values in digital form,
another register for temporarily storing the other sensor values.

12. Sensor chip according to claim 11 ,
wherein the other sensing element is one of a temperature sensor and a humidity sensor for compensating temperature or humidity dependent signal variations in the sensor signal, and
wherein the sensing element is one of a
a flow sensor;
a humidity sensor;
a gas sensor;
a pressure sensor.

13. Sensor chip according to claim 1 ,
wherein following parameters of the sensor chip are changeable:
the number of look-up tables,
the configuration of a look-up table,
a data path/processing sequence of the look-up tables,

sample points of the look-up tables,
the location of the look-up tables in the on-chip memory.

14. Sensor chip, comprising
a sensing element providing a sensor signal,
an on-chip memory,
a configuration of a look up table of dimension N stored in the on-chip memory for assigning an output value to a combination of N input values, the configuration of the look-up table including a number of sampling points per dimension, a position of the sampling points, and output values, and
a look up table engine for determining a corresponding output value in response to receiving a memory address for the look up table configuration and in response to receiving a sensor value derived from the sensor signal as one of the N input values,
a system controller configured to copy the memory address and the sensor value as one of the N input values to the look up table engine for generating the corresponding output value,
wherein the look up table engine is implemented as hardware,
different configurations of look up tables of dimension N stored in the on-chip memory each for assigning an output value to a combination of N input values,
wherein the system controller is configured to call the different look up tables in sequence,
wherein calling different look up tables is stored in form of a micro-program in the on-chip memory, and is executed by the system controller.

15. Sensor chip according to claim 14 ,
wherein following parameters of the sensor chip are changeable:
the number of look-up tables,
the configuration of a look-up table,
a data path/processing sequence of the look-up tables,

sample points of the look-up tables,
the location of the look-up tables in the on-chip memory.

16. Method for processing a sensor signal in a sensor chip, comprising
sensing a measure by means of a sensor element of the sensor chip,
deriving a sensor value from the sensor signal,
receiving a memory address for a configuration of a look up table,
applying the sensor value and the memory address as input values to the look up table configuration of dimension N stored in an on-chip memory of the sensor chip for assigning an output value to a combination of N input values, thereby generating the corresponding output value.

Assignees

• Sensirion Ag

Inventors

• Fuhrer Samuel

Classifications

• G06F13/16

  for access to memory bus (G06F13/28 takes precedence) · CPC title

• G01N27/00

  Investigating or analysing materials by the use of electric, electrochemical, or magnetic means (G01N3/00 – G01N25/00 take precedence; measurement or testing of electric or magnetic variables or of electric or magnetic properties of materials G01R) · CPC title

• G01N33/0006

  Calibrating gas analysers · CPC title

• G01D11/00 Primary

  Component parts of measuring arrangements not specially adapted for a specific variable (G01D13/00, G01D15/00 take precedence) · CPC title

• H04N1/60

  Colour correction or control {(H04N1/54 takes precedence)} · CPC title