AD7747ARUZ

The AD7747ARUZ is a 24-bit High Resolution Capacitance to Digital Converter with temperature sensor. The capacitance to be measured is connected directly to the device inputs. The architecture features inherent high resolution (24-bit no missing codes, up to 19.5-bit effective resolution). Each channel can be configured as single-ended or differential. The Σ-∆ capacitance to digital converter (CDC) is designed for single-ended or differential capacitive sensors with one plate connected to ground. The part has an on-chip temperature sensor with a resolution of 0.1°C and accuracy of ±2°C. The on-chip voltage reference and the on-chip clock generator eliminate the need for any external components in capacitive sensor applications. The AD7747 capacitance input range is ±8pF (changing) and it can accept up to 17pF common-mode capacitance (not changing), which can be balanced by a programmable on-chip digital-to-capacitance converter (CAPDAC).

• New standard in single chip solutions
• Interfaces to single or differential grounded sensors
• 10fF Accuracy
• 0.01% Linearity
• Common-mode (not changing) capacitance up to 17pF
• Simultaneous 50 and 60Hz rejection at 8.1Hz update
• Active shield for shielding sensor connection
• Temperature sensor on-chip
• Voltage input channel
• Internal clock oscillator
• 2-wire serial interface (I²C® compatible)
• 0.7mA Current consumption