The TC850 is a monolithic CMOS analog-to-digital converter (ADC) with resolution of 15-bits plus sign. It combines a chopper-stabilized buffer and integrator with a unique multiple-slope integration technique that increases conversion speed. The result is 16 times improvement in speed over previous 15-bit, monolithic integrating ADCs (from 2.5 conversions per sec up to 40 per sec). Only a voltage reference and a few noncritical passive components are required to form a complete 15-bit plus sign ADC. CMOS processing provides the TC850 with high-impedance differential inputs. Input bias current is typically only 30pA, permitting direct interface to sensors. Input sensitivity of 100 µV per least significant bit (LSB) eliminates the need for precision external amplifiers. The internal amplifiers are auto-zeroed, guaranteeing a zero digital output with 0V analog input. Conversions can be performed continuously or on command. Operating from ±5V supplies, the TC850 dissipates only 20mW. It is packaged in 40-pin plastic or ceramic dual-in-line packages (DIPs) and in a 44-pin plastic leaded chip carrier (PLCC), surface-mount package.

• 15-bit Resolution Plus Sign Bit
• Up to 40 Conversions per Second
• Integrating ADC Technique
  • Monotonic
  • High Noise Immunity
  • Auto-Zeroed Amplifiers Eliminate Offset Trimming
• Wide Dynamic Range: 96dB
• Low Input Bias Current: 30pA
• Low Input Noise: 30µVp-p
• Sensitivity: 100µV
• Flexible Operational Control
• Continuous or On-Demand Conversions
• Data Valid Output
• ± 5V Power Supply Operation, 20mW