128 Channel, 24-Bit Current to Digital ADC

The ADAS1128 is a 128-channel, current-to-digital, analog-to-digital converter (ADC). It contains 128 low power, low noise, low input current integrators, simultaneous sample-and-holds, and two high speed, high resolution ADCs with configurable sampling rate and resolutions up to 24 bits.

All converted channel results are output on a single LVDS self-clocked serial interface, which reduces external hardware.

An SPI-compatible serial interface allows configuration of the ADC using the SDI input. The SDO output allows the user to daisy-chain several ADCs on a single, 3-wire bus. The ADAS1128 uses the separate supply IOVDD to reduce digital noise effect on the conversions.

The ADAS1128 is in a 10 mm × 10 mm, mini-BGA package.

Applications

* Medical, industrial, and security CT scanner data acquisition

* Photodiode sensors

* Dosimetry and radiation therapy systems

* Optical fiber power monitoring

* X-ray detection systems

* High channel-count data acquisition systems (current or

voltage inputs)

* 128-channel, low level current-to-digital converter

* Up to 24-bit resolution

* Up to 19.7 kSPS (50.7 μs integration time)

* Simultaneous sampling

* No dead time, no loss of charge

* Ultralow noise (down to 0.4 fC [2500e−])

* User-adjustable full-scale range

* INL: ±0.025% of reading ±0.75 ppm of FSR* See data sheet for additional information