I hosted a webinar on June 16, 2023 on

"Current and resonance tracking in an ultrasonic drive circuit with an Arduino"

You can watch the recording on my YouTube Channel here: 

https://youtu.be/9npoCMlmqRM

Here is a link to the presentation notes.

Here is a link to the Arduino code.

Topics

In this webinar recording, I implemented current measurement and frequency and voltage amplitude control to create a feedback loop to track the resonance frequency and also to drive the target current.

I used an Arduino nano, JFET (amplitude control), sine wave generator chip, and an amplifier with a transformer.

Video outline:

• 0:00 Introduction to the topic
• 1:00 Pictures of drive circuit and ultrasonic scaler
• 3:10 Function generator DJ (a joke about manually controlling frequency and amplitude)
• 4:15 About Ultrasonic Advisors
• 5:30 Detailed outline
• 8:20 Quick overview of the drive logic of ultrasonic transducer driver control
• 11:20 Discussion of the impedance response of an ultrasonic scalpel
• 15:45 Previous circuit webinars
• 16:56 Current measurement circuit
• 19:18 Voltage amplitude control circuit with a P JFET
• 27:31 Block diagram of drive circuit and logic
• 28:32 Circuit pictures
• 30:15 Code overview/Arduino code review
• 36:24 Drive control logic explanation to search for the resonance frequency based off current measurement
• 37:20 Explanation of parts (Arduino, sine wave generator IC, amplifier, dental scaler ultrasonic transducer
• 39:29 Winding transformer
• 41:21 Live demonstration of circuit via oscilloscope, Arduino serial output, and visual micron displacement measurement
• 45:00 Displacement measurement at the maximum output of the circuit
  

***Announcement***

My next webinar will be on Friday, July 14, 2023 at 11AM EST. I will cover

"Transformer design for ultrasonic transducers drive circuits”

Here is the link to sign up for the upcoming webinar: https://www.ultrasonicadvisors.com/monthly-ultrasonic-webinar