GENERAL DESCRIPTION
The AD7152/AD7153 are 12-bit sigma-delta (Σ-Δ) capacitance-to-digital converters (CDCs). The capacitance to be measured is connected directly to the device inputs. The architecture features inherent high resolution (12-bit no missing codes, up to 12-bit effective resolution) and high linearity (±0.05%). The AD7152/AD7153 have four capacitance input ranges per operation mode, ±0.25 pF to ±2 pF in differential mode and 0.5 pF to 4 pF in single-ended mode.

FEATURES
   Capacitance-to-digital converters
      Interfaces to floating sensors
      Resolution down to 0.25 fF (that is, up to 12 ENOB)
      Linearity: 0.05%
      Common-mode (not changing) capacitance up to 5 pF
      Four capacitance ranges selectable per operation mode
         ±0.25 pF to ±2 pF in differential mode
         0.5 pF to 4 pF in single-ended mode
      Tolerant of parasitic capacitance to ground up to 50 pF
      Conversion time per channel: 5 ms, 20 ms, 50 ms, and 60 ms
   Internal clock oscillator
   2-wire serial interface (I2C-compatible)
   Power
      2.7 V to 3.6 V single-supply operation
      100 μA current consumption
   Operating temperature: −40°C to +85°C
   10-lead MSOP
  
APPLICATIONS
   Automotive, industrial, and medical systems for
      Pressure measurement
      Position sensing
      Level sensing
      Flowmeters
      Humidity sensing