Systems and methods for testing MEMS arrays and associated ASICs
Described herein are methods and systems for testing transducers and associated integrated circuits. In some cases, a method or system described herein can comprise modulating a bias voltage using a test signal in order to produce a modulated bias voltage signal useful in testing a plurality of transducers of a transducer array in parallel.
1. A method for testing a transducer array, the method comprising:
applying a test signal to a bias voltage signal to generate a modulated bias voltage signal;
providing the modulated bias voltage signal to an ultrasound transducer array;
measuring an output voltage signal of the ultrasound transducer array; and
determining whether the measured output voltage signal is within a set of expected output limits.
2. The method of claim 1 , wherein the output voltage signal is measured from a MEMS transducer or low-noise amplifier (LNA) of the ultrasound transducer array.
3. The method of claim 2 , further comprising performing the measuring and determining for each MEMS transducer or LNA of a row of the ultrasound transducer array in parallel.
4. The method of claim 3 , further comprising performing the measuring and determining for each row of the ultrasound transducer array in sequence.
5. The method of claim 2 , further comprising performing the measuring and determining for each MEMS transducer or LNA of a column of the ultrasound transducer array in parallel.
6. The method of claim 5 , further comprising performing the measuring and determining for each column of the ultrasound transducer array in sequence.
7. The method of claim 1 , further comprising determining a total error number based on a total number of measured output signals that are determined not to be within the set of expected output limits and identifying the ultrasound transducer array as rejected if the total error number exceeds an error count limit.
8. The method of claim 1 , wherein the set of expected output limits comprises an output voltage amplitude within 30% of an expected output voltage amplitude value.
9. The method of claim 1 , wherein the set of expected output limits comprises a signal frequency within 5% of an expected signal frequency value.
10. The method of claim 1 , wherein the providing the modulated bias voltage signal provides a non-mechanical stimulation of the array.
11. The method of claim 1 , wherein the providing the modulated bias voltage signal comprises providing a voltage via direct electrical connection with the ultrasound transducer array.
12. A system for testing a transducer array, the system comprising:
an ultrasound transducer array comprising a plurality of MEMS transducers;
a bias voltage signal source;
a test voltage signal source connected to the bias voltage signal source and the ultrasound transducer array in series;
one or more controllers configured to perform the steps of:
measuring an output voltage signal of the ultrasound transducer array; and
determining whether the measured output voltage signal is within a set of expected output limits;
a plurality of low-noise amplifiers (LNAs) connected in series with the ultrasound transducer array and the one or more controllers.
13. The system of claim 12 , wherein the output voltage signal is measured from one or more of a MEMS transducer or LNA of the ultrasound transducer array.
14. The system of claim 13 , wherein the controller is configured to perform the measuring and determining for each MEMS or LNA of a row of the ultrasound transducer array in parallel.
15. The system of claim 14 , wherein the controller is configured to perform the measuring and determining for each row of the ultrasound transducer array in sequence.
16. The system of claim 13 , wherein the controller is configured to perform the measuring and determining for each MEMS or LNA of a column of the ultrasound transducer array in parallel.
17. The system of claim 16 , wherein the controller is configured to perform the measuring and determining for each column of the ultrasound transducer array in sequence.
18. The system of claim 12 , wherein the controller is further configured to determine a total error number based on a total number of measured output signals that are determined not to be within the set of expected output limits, and wherein the controller is further configured to identify the ultrasound transducer array as rejected if the total error number exceeds an error count limit.
19. The system of claim 12 , wherein the set of expected output limits comprises an output voltage amplitude within 30% of an expected output voltage amplitude value.
20. The system of claim 12 , wherein the set of expected output limits comprises a signal frequency within 5% of an expected signal frequency value.