Hi folks, I've experienced some PLL burnout issues similar to the ones seen here:
I've made my first PCB and I would like to use it for an upcoming workshop I'm going to be giving. However, I am concerned about others in the workshop experiencing the issue to. The application uses video (hence PLL), so once we've lost that functionality we're soaked.
I'm not an electrical engineer, but here's what seems to happen. Introducing a short into the circuit surely seems to fry the chip, which I have certainly done. Maybe I'm crazy but I'm getting superstitious about plugging and unplugging the DC power and plugging and unpluggin the Prop Plug. After the PLL is fried, there's a big power draw and the Propeller and the voltage regulator get extremely hot.
What I would love to know is if there are some simple elements i can introduce to my circuit--it's a simple circuit to help prevent this error from happening. For instance, what values for decoupling capacitors are the best--ceramic or aluminum? Would adding diodes or some simple circuit to prevent electrical backflow in a short-circuit situation help? Is one brand of voltage regulator better than another? Should there be a pullup resistor attached to RESn (I've noticed that plugging and unplugging the Plug seems to reset the prop). Any tips on circuit design or parts to help prevent this issues would be greatly appreciated.