US 11,949,427 B2
Force sensing systems
Gavin McVeigh, Edinburgh (GB)
Assigned to Cirrus Logic Inc., Austin, TX (US)
Filed by Cirrus Logic International Semiconductor Ltd., Edinburgh (GB)
Filed on Nov. 4, 2020, as Appl. No. 17/089,457.
Claims priority of provisional application 62/949,011, filed on Dec. 17, 2019.
Claims priority of provisional application 62/948,984, filed on Dec. 17, 2019.
Prior Publication US 2021/0181044 A1, Jun. 17, 2021
Int. Cl. H03M 1/78 (2006.01); G01L 1/22 (2006.01); H03M 1/06 (2006.01); H03M 1/16 (2006.01); H03M 1/66 (2006.01); H03M 1/80 (2006.01); H03F 3/45 (2006.01)
CPC H03M 1/785 (2013.01) [G01L 1/2268 (2013.01); H03M 1/0607 (2013.01); H03M 1/16 (2013.01); H03M 1/662 (2013.01); H03M 1/802 (2013.01); H03F 3/45 (2013.01); H03M 1/808 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A compensation circuit for compensating for an offset voltage that is present in an output signal output by a force sensor, the compensation circuit comprising:
voltage divider circuitry, the voltage divider circuitry configured to receive a bias voltage that is also supplied to the force sensor and to output a control voltage derived from the bias voltage, wherein a component mismatch ratio of the voltage divider circuitry is adjustable to correspond to a component mismatch ratio of the force sensor;
current generator circuitry configured to receive the control voltage and to generate a compensating current based on the received control voltage; and
amplifier circuitry configured to receive a signal output by the force sensor and the compensating current and to output a compensated output signal in which the offset voltage is at least partially cancelled.