I'm trying to arrange ICSP for PIC16F914.
My board is powered by 3.3V, while PIC's programming voltage is 4.5-5V. This means I need to isolate normal CPU VDD from VDD coming from the programmer (ICD2).
I can feed VDD via a schottky but this means I will drop 100-200 mV on VDD during normal operation. The voltage drop will also change all the time since it's current dependant.
It seems very stupid to me that I need 5V on VDD to program PIC which was designed to run on low voltages (2-3V).
Any ideas how can I isolate VDD on board from 5V_VDD coming from the flash programmer without using this diode?
My board is powered by 3.3V, while PIC's programming voltage is 4.5-5V. This means I need to isolate normal CPU VDD from VDD coming from the programmer (ICD2).
I can feed VDD via a schottky but this means I will drop 100-200 mV on VDD during normal operation. The voltage drop will also change all the time since it's current dependant.
It seems very stupid to me that I need 5V on VDD to program PIC which was designed to run on low voltages (2-3V).
Any ideas how can I isolate VDD on board from 5V_VDD coming from the flash programmer without using this diode?