AFE2256 - 256-Channel Analog Front End (AFE) for Digital X-Ray, Flat-Panel Detectors

The AFE2256 is a 256-channel, analog front-end (AFE) designed to suit the requirements of flat-panel detector (FPD)-based digital x-ray systems. The device includes 256 integrators , a programmable gain amplifier (PGA) for full-scale charge level selection, a correlated double sampler (CDS) with dual banking, and 256:4 analog multiplexers.

The device also features four 16-bit successive-approximation register (SAR) analog-to-digital converters (ADCs). Serial data from the ADCs are available in low-voltage differential signaling (LVDS) format.

The Nap and power-down modes enable substantial power saving that is especially useful in battery-powered systems.

To request a full datasheet or other design resources: request AFE2256

• 256 Channels
• On-Chip, 16-Bit ADC
• Photodiode Short Immunity
• High Performance:
  • Noise: 750 Electrons RMS
    (1.2-pC Input Charge Range)
  • Low Correlated Noise
  • Integral Nonlinearity:
    ±2 LSB with Internal 16-Bit ADC
  • Scan Time:
    • < 20 µs to 204.8 µs
• Integration:
  • Six Selectable, Full-Scale Input Ranges:
    0.6 pC (Min) to 9.6 pC (Max)
  • Internal Timing Generator (TG)
  • Built-In Correlated Double Sampler
  • Pipelined Integrate and Read for Improved
    Throughput: Allows Data Read During
    Integration
  • Serial LVDS Output
• Simple Power-Supply Scheme:
  • AVDD1 = 1.85 V
  • AVDD2 = 3.3 V
• Low Power Consumption
• Nap and Total Power-Down Mode
• Custom Chip-On-Film (COF) Packages