The MAX172 is a complete 12-Bit analog-to-digital converter (ADC) that combines high speed, low power consumption, and an on-chip voltage reference. The conversion time is 10ps. The buried zener reference provides low drift and low noise performance. External component requirements are limited to only decoupling capacitors for the power supply and reference voltages. On-chip clock circuitry is also included which can either be driven from an external source, or in stand-alone applications, can be used with a crystal. The MAX172 uses a standard microprocessor interface architecture. Three-state data outputs are controlled by Read (RD\) and Chip Select (CS\) inputs. Data access and bus release times of 90 and 75ns respectively ensure compatibility with most popular microprocessors without resorting to wait states.