TESTING OF NON-VOLATILE MEMORY CHARGE PUMPS TO ENSURE RELIABLE VOLTAGE GENERATION USING CLOCK FREQUENCY
Original Publication Date: 1999-Jun-01
Included in the Prior Art Database: 2002-Aug-09
For security conscience devices e.g. Smartcards, charge pumps required for high voltage generation on non-volatile memories are not usually pinned out on the device to make tampering of voltages con- trolling EEPROM operation more complex and dif- ficult for the potential hacker. This has the draw- back that testing of charge pump voltages via a suit- able pad at probe or package pin at final test is NOT possible. Some devices may also be pad limited or as is the case for Smartcards, not enough package pins available to bond charge pump outputs. This is especially the case for deep sub-micron non-volatile memory technologies e.g. EEPROM, EPROM, FLASH EEPROM which require multiple charge pump voltages for single Vdd operation.