Analog Devices Inc. AD7152BRMZ-REEL

Description
The AD7152/AD7153 are 12-bit sigma-delta (Σ-Δ) capacitance-to-digital converters (CDCs) designed for interfacing with floating capacitive sensors. They feature high resolution (up to 12 ENOB) and linearity (±0.05%). The devices have four capacitance input ranges per operation mode, allowing for measurements from 0.25 pF to 12 pF in differential mode and 0.5 pF to 4 pF in single-ended mode. They can tolerate up to 5 pF of common-mode capacitance and parasitic capacitance to ground up to 50 pF. The conversion time per channel is selectable between 5 ms, 20 ms, 50 ms, and 60 ms. The AD7152 has two capacitance input channels, while the AD7153 has one. Both devices have an internal clock oscillator and a 2-wire, PC-compatible serial interface. They operate with a single power supply from 2.7 V to 3.6 V and are specified over the temperature range of -40°C to 85°C.

Features
Capacitance-to-digital converters
Interfaces to floating sensors
Resolution down to 0.25 fF (up to 12 ENOB)
Linearity: 0.05%
Common-mode capacitance up to 5 pF
Four capacitance ranges selectable per operation mode
10.25 pF to 12 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 ('C-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 package

Applications
Automotive, industrial, and medical systems for
Pressure measurement
Position sensing
Level sensing
Flowmeters
Humidity sensing