The LHA7732 is a high-performance, single-chip analog-to-digital converter (ADC). The ADC supports two modes of operation to achieve the best balance between power consumption and resolution.
Two-channel multiplexer can select external signal measurement and internal ADC test signal. There is a mode to test the internal noise by shorting the input circuit.
Fourth order intrinsically stable modulator provides excellent low noise and linearity performance. The modulator output is filtered and decimated by an on-chip digital filter to generate the ADC conversion result. Digital FIR filters provide data rates from 250 to 4kSPS. The SINC filter provides data rates up to 128kSPS. The high-pass filter (HPF) has a programmable corner frequency. On-chip gain and offset adjustment registers support system calibration. A sync input controls the timing of ADC conversions. A shutdown input puts the ADC in shutdown mode.
The LHA7732 is housed in a compact 24-lead 5mm x 4mm QFN package and is fully rated for operation from –40°C to +85°C, with a maximum operating temperature range of –50°C to +125°C.

Product Features

  • Operating mode
  • Low power mode

- 3.8mW

- 128.5dBSNR(250 SPS)FIR filter

- 109.3dB SNR(16k SPS)SINC filter

  • High resolution mode:

- 6mW

- 136dB SNR(250 SPS)FIR filter

- 110.6dB SNR(32k SPS)SINC filter

  • THD:–120dB
  • CMRR:125dB
  • Dual Channel Multiplexer
  • Intrinsically stable modulator
  • Fast Response Out-of-Range Detector
  • Flexible digital filters:

- Sinc + finite impulse response (FIR) + infinite impulse response (IIR) (optional)

- Linear or minimum phase options

- Programmable High Pass Filter

  • Offset Error and Gain Error Calibration
  • SYNC input
  • Digital Supply: 1.8V to 3.3V
  • Analog Power: 5V or ±2.5V

Application Scenario

  • Energy exploration
  • Earthquake monitoring
  • High precision instrument