TI PGA970QPHPR

The PGA970 is a highly integrated system-on-chip LVDT sensor signal conditioner with advanced signal processing capabilities. The device features a three-channel, low-noise, programmable gain analog front-end that allows direct connection of sensing elements, followed by three independent 24-bit Δ-Σ ADCs. In addition, the device includes a digital signal demodulation module connected to an integrated ARM-Cortex M0 MCU, enabling execution of custom sensor compensation algorithms stored in the device's non-volatile memory. The device communicates with external systems via SPI, OWI, GPIO, or PWM digital interfaces. Analog output is supported through a 14-bit DAC and a programmable gain amplifier, providing reference or absolute voltage output. Sensing element excitation is achieved via an integrated waveform generator and waveform amplifier. Waveform signal data is stored in a dedicated RAM region based on user-defined settings. In addition to the primary functional components, the PGA970 includes supplementary support circuitry — such as device diagnostics, sensor diagnostics, and an integrated temperature sensor. These circuits collectively provide protection and integrity information for the overall system and sensing elements. The device also incorporates a gate controller circuit that works with an external depletion-mode MOSFET to regulate the device supply voltage when the system supply voltage exceeds 30V.

• Analog Features:
  • Programmable-gain analog front end for LVDT sensors
  • Excitation waveform generator and amplifier
  • Dual-channel 24-bit ADC with amplitude and phase demodulator
  • 24-bit auxiliary ADC
  • On-chip internal temperature sensor
  • 14-bit output DAC with programmable gain
  • Built-in diagnostics
• Digital Features:
  • ARM Cortex-M0 microcontroller
  • 16KB ferroelectric RAM (FRAM) program memory
  • 2KB general-purpose RAM
  • 512B RAM waveform generator lookup table
  • 8MHz on-chip oscillator
• Peripheral Features:
  • SPI
  • Single-wire interface (OWI)
  • Ratiometric and absolute voltage outputs
• General Features:
  • Operating supply voltage range: 3.5V to 30V
  • Ambient temperature range: -40°C to +125°C
  • DMOS gate controller for extended supply voltage range (>30V)

• Position sensor signal conditioning
• Linear Variable Differential Transformer (LVDT)
• Rotary Variable Differential Transformer (RVDT)
• Resolver
• RLC measurement