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