I am trying to remove the timer mechanism from my Sonicare toothbrush for an R&D project. I'm not very interested in writing new firmware. This thread has brought up the same issue with no success. Has anybody successfully done this before? Thank you for your time.

 

There is no standalone timer, just the msp430 microcontroller.

 

Your only chance is probably to remove the crystal (Y1). I'm guessing it's a watch crystal and it might be what sets the timing to turn off. That's the only shot you've got though.

 

I second Kubeek's comment in post #1. Perhaps you can use the entire PCB assembly and extract the timer information you need and just the other parts go along for the ride.

 

Thank you for your help everybody. What I ended up doing was adding a dc power supply pumping in 2.5v in parallel with the batteries. This allowed the motor to run continuously for long period of time without kicking the processor into a 'charging mode'. Then I noticed there was a change in voltage across the button contacts when the toothbrush was on. I soldered leads on the two polar ends of the contacts and set up a circuit to monitor the change of voltage. Using an Arduino, if the voltage change (ie the toothbrush turned off) I would add a voltage to another circuit that shorted the terminals for the button to turn the toothbrush on.

 

Thank you for your help everybody. What I ended up doing was adding a dc power supply pumping in 2.5v in parallel with the batteries. This allowed the motor to run continuously for long period of time without kicking the processor into a 'charging mode'. Then I noticed there was a change in voltage across the button contacts when the toothbrush was on. I soldered leads on the two polar ends of the contacts and set up a circuit to monitor the change of voltage. Using an Arduino, if the voltage change (ie the toothbrush turned off) I would add a voltage to another circuit that shorted the terminals for the button to turn the toothbrush on.

How long do you need to brush your teeth????