US 12,072,254 B2
Electric circuitry with differently oriented ring oscillators for strain measurement
Friedrich Bahnmüller, Karlsruhe (DE); Oliver Hertner, Graben-Neudorf (DE); Frank Lemke, Mutterstadt (DE); and Georg Jedelhauser, Bad Soden (DE)
Assigned to Sciosense B.V., AE Eindhoven (NL)
Appl. No. 17/597,687
Filed by Sciosense B.V., AE Eindhoven (NL)
PCT Filed Jul. 20, 2020, PCT No. PCT/EP2020/070457
§ 371(c)(1), (2) Date Jan. 18, 2022,
PCT Pub. No. WO2021/028156, PCT Pub. Date Feb. 18, 2021.
Claims priority of application No. 19191055 (EP), filed on Aug. 9, 2019.
Prior Publication US 2022/0260437 A1, Aug. 18, 2022
Int. Cl. G01L 1/18 (2006.01); G01B 7/16 (2006.01)
CPC G01L 1/183 (2013.01) [G01B 7/18 (2013.01)] 15 Claims
OG exemplary drawing
 
1. An electric circuitry comprising:
at least one first ring oscillator and at least one second ring oscillator being arranged on a substrate in different orientations;
a time-to-digital converter having a converter ring oscillator; and
a processing circuit,
wherein the at least one first ring oscillator comprises at least one first delay chain and the at least one second ring oscillator comprises at least one second delay chain,
wherein the at least one first delay chain of a plurality of delay elements and the at least one second delay chain of a plurality of delay elements are arranged on the substrate,
wherein the respective delay elements of the at least one first and second delay chains are configured to provide a propagation delay time depending on strain applied to the substrate,
wherein the delay elements of the at least one first delay chain have other orientations on the substrate than the delay elements of the at least one second delay chain,
wherein the at least one first ring oscillator is configured to operate with a first oscillation frequency and the at least one second ring oscillator is configured to operate with a second oscillation frequency,
wherein the converter ring oscillator has an output side configured to provide an output signal of the converter ring oscillator based on a state of the converter ring oscillator,
wherein a first time is determined by a period duration of the at least one first ring oscillator, the period duration of the at least one first ring oscillator being dependent on the propagation delay time of the delay elements of the at least one first ring oscillator,
wherein a second time is determined by a period duration of the at least one second ring oscillator, the period duration of the at least one second ring oscillator being dependent on the propagation delay time of the delay elements of the at least one second ring oscillator, and
wherein the processing circuit is configured to determine a magnitude of the strain applied on the substrate based on a first state of the converter ring oscillator at the first time and a second state of the converter ring oscillator at the second time.