AD698APZ

The AD698APZ is a complete, monolithic Linear Variable Differential Transformer (LVDT) signal conditioning subsystem from Analog Devices. It is designed to work in conjunction with LVDTs to convert the mechanical position of a transducer into a unipolar or bipolar DC voltage with a high degree of accuracy and repeatability.

Key features of the AD698APZ include:

• Integrated Circuitry: All circuit functions are included on the chip, simplifying system design and reducing the need for external components.
• High Accuracy: Offers exceptional linearity of 0.05%, ensuring precise conversion of LVDT output to a scaled DC signal.
• Flexible Configuration: Capable of operating with half-bridge LVDTs, LVDTs connected in series-opposed configuration (4-wire), and Rotary Variable Differential Transformers (RVDTs).
• Internal Oscillator: Contains a low-distortion sine wave oscillator to drive the LVDT primary, eliminating the need for an external oscillator.
• Synchronous Demodulation: Features two synchronous demodulation channels to detect primary and secondary amplitudes, providing a robust and reliable signal conversion process.
• Ratiometric Output: The device divides the output of the secondary by the amplitude of the primary and multiplies by a scale factor, eliminating errors due to primary drive amplitude drift.
• Wide Operating Range: Operates over a wide temperature range of -40°C to 85°C, making it suitable for various industrial and automotive applications.
• Single Chip Solution: Provides a single-chip solution for LVDT signal conditioning, reducing board space and cost.
• Unipolar or Bipolar Output: Offers the flexibility to choose between unipolar or bipolar output, depending on the application requirements.
• No Adjustments Required: The device is factory-calibrated, eliminating the need for user adjustments.

The AD698APZ is widely used in precision data acquisition systems, medical instruments, industrial measurements, and geophysical exploration, where high accuracy and reliability are crucial. Its unique ratiometric architecture eliminates many of the drawbacks associated with traditional LVDT interface methods, providing improved temperature stability and sensor interchangeability.