US 12,381,539 B2
Baseline restorer circuit
Matthias Steiner, Graz (AT)
Assigned to AMS INTERNATIONAL AG, Jona (CH)
Appl. No. 18/554,486
Filed by ams International AG, Jona (CH)
PCT Filed Apr. 11, 2022, PCT No. PCT/EP2022/059579
§ 371(c)(1), (2) Date Oct. 9, 2023,
PCT Pub. No. WO2022/218901, PCT Pub. Date Oct. 20, 2022.
Claims priority of application No. 2105196 (GB), filed on Apr. 12, 2021.
Prior Publication US 2024/0195392 A1, Jun. 13, 2024
Int. Cl. H03H 11/12 (2006.01); H03F 3/45 (2006.01)
CPC H03H 11/1217 (2013.01) [H03F 3/456 (2013.01); H03H 11/1291 (2013.01); H03F 2200/261 (2013.01); H03F 2200/471 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A baseline restorer circuit, the baseline restorer circuit comprising:
a controller;
a sample control circuit arranged to receive an input voltage signal that is output from a circuit stage comprising an amplifier, wherein the sample control circuit is configured to capture a sample of the input voltage signal at a sampling time in response to receiving a first control signal from the controller;
an analogue processing stage arranged to receive the sample of the input voltage signal and a constant baseline reference voltage and selectively process the sample of the input voltage signal to provide an output voltage;
a transconductance stage configured to convert the output voltage to a compensation current and supply the compensation current to an input of the circuit stage; and
a change detector configured to monitor if the input voltage signal changes during a time interval around the sampling time, and if no change is detected in the input voltage signal during the time interval, the controller is further configured to transmit a second control signal to the analogue processing stage to control the analogue processing stage to process the sample of the input voltage signal,
wherein the change detector comprises a change detector stage arranged to continuously receive the input voltage signal, and
wherein commencement and expiry of the time interval is controlled by the controller transmitting a third control signal to the change detector.