RE: Programmable power is great, but review it carefully

Gough Lui — Sat, 29 Sep 2018 07:20:45 GMT

Always a good thing to remember nowadays, as components are not merely components. Anything with configurable Flash/EEPROM variables, eFuses, or even external strapping resistors will need to be configured appropriately for each design otherwise such unexpected events may happen.

It's probably more commonly thought of around microcontrollers and FPGAs where silly things like not configuring your clock source correctly will render your IC "hung". People wanting to bread-board their Atmega328P-based designs without an external crystal have to ensure the fuses are set correctly to use the internal resonator. Likewise, configuring where the FPGA loads its initial configuration from is almost equally important otherwise it won't load anything at all.

I guess there's always a price to all that configurability. Lucky you could patch in an external source of power to "salvage" it by reprogramming it from there - maybe a lesson to learn for others in breaking out unused connections to test pads to give you the maximum salvageability in the design.

- Gough

RE: Programmable power is great, but review it carefully

jw0752 — Sat, 29 Sep 2018 04:48:56 GMT

Hi Chris,

Thanks for sharing. If we read and listen there is always a possibility to learn from someone else and not have to suffer our own educational experiences.

John