Trimbit circuit for flash memory integrated circuits

摘要

A trimbit circuit for flash memory integrated circuits is described. The trimbit circuit is used to store the addresses of bad rows and/or columns in flash memory arrays. Furthermore the trimbit circuit is used to store the trimbits for trimable circuits in the integrated circuit, i.e. voltage references, precision oscillator, etc. The invention includes a row of flash memory trimcells and a trimcell differential amplifier circuit. The trimcell differential amplifier circuit can serially shift in trimbits into a latch and serially shift out trimbits without having to program the flash memory trimcells. The final settings of the trimbits can be programmed by means of a high voltage buffer. A non-overlapping clock generator and additional logic is also included to control the circuit. <IMAGE> <IMAGE>