Replacing the BigTrak Electronics
Last updated: 28 Jan 2012 - 17:00
Underneath the Original BigTrak PCB: Not a lot to see, this is a cheap PCB with an epoxy coated silicon-on-board processor.
Internally the BigTrak is a fairly typical modern toy, the circuit board in it with an epoxy covered ASIC in the middle looks like the main circuit board in any cheap radio controlled car. The motor driver H-bridges are built out of discreet transistors, but as the motors only draw about 25mA running current the transistors are nothing remarkable. Quite possibly the most expensive part is the 0.1" header that the keypad plugs into.
H-Bridge Tutorial
Last updated: 25 Jan 2012 - 20:21
The H-bridge is a circuit used in electronic control of high current devices, particularly where the device polarity may be reversed, e.g. DC motors. The name comes from the fact that the circuit typically looks like a letter "H".