The MicroConverter® family from Analog Devices Inc. integrates high precision A/D and D/A converters on chip with an industry standard Flash microcontroller. This paper focuses on some of the design challenges met in the development of the first two MicroConverters in the planned family, namely : the ADuC812 and the ADuC824. These Challenges relate specifically to the areas of Flash memory integration, automatic and self ADC calibration, precision DC specifications and clock synchronization schemes.