Analog Devices Inc. EVAL-CN0552-PMDZ Evaluation Board

Analog Devices Inc. EVAL-CN0552-PMDZ Evaluation Board is a demonstration and development platform for the AD7746 Capacitance-to-Digital Converter (CDC). The AD7746 consists of a second-order (Σ-Δ or charge balancing) modulator and a third-order digital filter. It works as a CDC for the capacitive inputs and as a classic Analog-to-Digital Converter (ADC) for the voltage input or the voltage from a temperature sensor. In addition to the converter, the AD7746 integrates a multiplexer, an excitation source and CAP DACs for the capacitive inputs, a temperature sensor, a voltage reference for the voltage and temperature inputs, a complete clock generator, control and calibration logic, and an I2C-compatible serial interface. The device has two capacitive inputs, which can be configured as single-ended or differential.

The Analog Devices Inc. EVAL-CN0552-PMDZ Evaluation Board includes a pre-mounted AD7746 CDC in a 16-lead TSSOP package. The Evaluation Board features an I2C Pmod™ connector and is designed for use with the EVAL-ADICUP3029 Development Board (not included). 

Features

  • AD7746 24-Bit Capacitance-to-Digital Converter
  • Designed to work with the EVAL-ADICUP3029 Development Board (not included)
  • Compatible with I2C Pmod platform boards, with an I/O voltage from 2.7V to 5.5V
  • ±4.096pF input range suits wide array sensors
  • Extended input range circuit provides ±50pF input range
  • 4.2aF RMS resolution @ 9.1sps conversion rate
  • Auxiliary temperature sensor and voltage input for system-level calibration

Required Equipment

  • EVAL-CN0552-PMDZ Reference Design Board
  • EVAL-ADICUP3029 Development Board
  • ADuCM3029_demo_cn0552.hex file
  • ADuCM3029_demo_cn0552 source code
  • 2x 2pF capacitors
  • Micro-USB to USB-A cable
  • PC/Laptop with an available USB port
  • IIO Oscilloscope software 

Application Notes

  • Circuit Note CN-0552: Capacitance to Digital Converter with Extended Range
  • Extending the Capacitive Input Range of the AD7745/AD7746 Capacitance-to-Digital Converter
  • Using CDCs to Control Motion for Sample Aspiration

Design Resources

  • Schematic Diagram
  • Bill of Materials
  • PCB Layout

Board Layout

Analog Devices Inc. EVAL-CN0552-PMDZ Evaluation Board

Block Diagarm

Block Diagram - Analog Devices Inc. EVAL-CN0552-PMDZ Evaluation Board

Setup Example

Analog Devices Inc. EVAL-CN0552-PMDZ Evaluation Board

Analog Devices Inc. EVAL-CN0552-PMDZ Evaluation Board