I am trying to wring the best possible performance out of a pair of cheap ultrasonic transducers. The drive signal comes from a bridge output stage running on 3.7 volts.
I have measured the capacitance of the sensor and tried to tune it with an inductor, but find that this path leads nowhere, I get less signal than before. A transformer seems to be the only answer.
I was wondering if anyone knows much about the failure mode of these transducers if I exceed the maximum ratings. In trying to produce a short burst, I have found it possible to "unring" the transducer by applying several cycles of drive in antiphase at the end of the burst, but the start of the burst could well be speeded up. I thought that maybe 100 volts, but only for a few cycles until the sound amplitude built up to the continuous level at 30 volts. If the failure is caused by overheating or mechanical failure I should be able to get away with it, but if it's dielectric breakdown then I'm sunk.
Any comments?
I have measured the capacitance of the sensor and tried to tune it with an inductor, but find that this path leads nowhere, I get less signal than before. A transformer seems to be the only answer.
I was wondering if anyone knows much about the failure mode of these transducers if I exceed the maximum ratings. In trying to produce a short burst, I have found it possible to "unring" the transducer by applying several cycles of drive in antiphase at the end of the burst, but the start of the burst could well be speeded up. I thought that maybe 100 volts, but only for a few cycles until the sound amplitude built up to the continuous level at 30 volts. If the failure is caused by overheating or mechanical failure I should be able to get away with it, but if it's dielectric breakdown then I'm sunk.
Any comments?
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