US 12,105,127 B2
Detection circuit and apparatus based on equipotential shielding
Qichao Zhao, Beijing (CN); Ran Yang, Beijing (CN); and Zhao Li, Beijing (CN)
Assigned to KINGFAR INTERNATIONAL INC., Beijing (CN)
Filed by KINGFAR INTERNATIONAL INC., Beijing (CN)
Filed on Dec. 27, 2022, as Appl. No. 18/088,931.
Claims priority of application No. 202210909464.9 (CN), filed on Jul. 29, 2022.
Prior Publication US 2024/0036091 A1, Feb. 1, 2024
Int. Cl. G01R 27/02 (2006.01); G01L 1/18 (2006.01); G01R 1/30 (2006.01)
CPC G01R 27/02 (2013.01) [G01L 1/18 (2013.01); G01R 1/30 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A detection circuit based on equipotential shielding for detecting an array piezoresistive sensor, the array piezoresistive sensor comprises a plurality of contact elements, a plurality of row leads and a plurality of column leads, an end of each of the plurality of contact elements is connected to one of the plurality of row leads and a second end of each of the plurality of contact elements is connected to one of the plurality of column leads, wherein,
the detection circuit comprises at least one group of row control circuits, at least one group of column control circuits, multiple groups of shielding circuits, an analog-to-digital converter (ADC) module, a first power supply terminal, and a second power supply terminal, each group of the multiple groups of shielding circuits comprises an inverse adder and a row pull-up resistor;
a first connection end of each group of the at least one group of row control circuits is configured to be connected to the plurality of row leads of the array piezoresistive sensor; a control end of each group of the at least one group of row control circuits is connected to a main control chip for outputting a control signal; a second connection end of each group of the at least one group of row control circuits is connected to the first power supply terminal; the row pull-up resistor is connected to the plurality of row leads; another end of the row pull-up resistor is connected to the second power supply terminal; each of the plurality of row leads corresponds to one of the row pull-up resistors; each column lead of the array piezoresistive sensor is connected to one input end of the inverse adder; an output end of the inverse adder is connected to a first connection end of the at least one group of column control circuits, a reference voltage end of the inverse adder is connected to the second power supply terminal, a control end of each group of the at least one group of column control circuits is connected to the main control chip, and a second connection end of each group of the at least one group of column control circuits is connected to the ADC module;
the at least one group of row control circuits is configured to receive a first control signal from the main control chip to perform a row collection;
the at least one group of column control circuits is configured to receive a second control signal from the main control chip to perform a column collection;
the at least one group of row control circuits and the at least one group of column control circuits are configured to cooperate to select a contact element to be detected from the plurality of contact elements;
the at least one group of column control circuits is configured to receive a collection signal of the inverse adder and transmit the collection signal to the ADC module;
the ADC module is configured to convert the received collection signal into a digital signal and transmit the digital signal to the main control chip;
the multiple groups of shielding circuits are configured to provide a potential for unselected contact elements so that equal potentials are enabled at both ends of the unselected contact elements;
a voltage of the first power supply terminal is different from a voltage of the second power supply terminal.