Minus 55 to plus 200 deg C 12 bit analog-to-digital converter

A 12 bit successive approximation analog to digital converter that offers moderately high speed precision data conversion at a reasonable level of cost and complexity is studied. The ADCH10HT extends this capability over a temperature range of -55 to +200 C. No missing-code performance is maintained over the entire temperature range. The converter is completely self-contained with internal clock and +10 volt reference. The CMOS devices offer low power dissipation, so that the internal temperature of the hybrid circuit does not rise as much from self heating. In CMOS circuits, pn junction leakage currents are returned to the supplies so that the logic keeps working at temperatures up to 250 C.