PDF datasheet for the Microchip PIC16F628 flash microcontroller, 1.68 MB in size. It describes the pin functions, internal oscillator, comparators, USART, timers, configuration bits and the electrical limits of this 18-pin device. In repair work it helps locate VDD, VSS, MCLR and the programming pins for in-circuit reading or reflashing, and confirms valid supply ranges when a board behaves erratically. Check whether the fitted chip is the original PIC16F628 or the later A version, as programming details differ slightly.
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