I have created a circuit for my Senior Design project at my uni. This circuit is meant to receive a signal from a contact microphone attached to a brass instrument, pre-amplify it, and analyze to find the pitch of the note played on the horn. Once the frequency is found, the board then does two things:
- Control an H-Bridge consisting of IRF3205s and a HIP4080AIBZ full-bridge gate driver
- Send frequency data over Bluetooth using a DSD HM-19 bluetooth module
When testing the circuit, we programmed the Teensy 4.0 to do a PWM signal sweep on two pins: PWM_A and PWM_B, with PWM_A being a non-inverting input for the HIP4080AIBZ and PWM_B being an inverting input.
When the board was turned on, the Teensy booted up and began driving the motor. It got maybe a half second into the sweep and then died. The motor started turning during that half second, but stopped once the teensy died.
This circuit is powered by a 3S LiPo Battery.
Here are some screenshots of the schematic and the PCB. Do you guys see any glaring issues here? What could have killed the teensy? Did >3.3v get applied to one of the output pins somehow? Could the voltage regulator have failed somehow?
NOTE: Originally, the voltage regulator used was an LM317T, but after finding that the regulator was not regulating to 5V, we changed to an LM1086IT-5.0. 2oz copper was used, and the motor is a BaneBots 550 motor.