Texas Instruments AFE0256GBTD

Description
The AFE0256 is a 256-channel analog front-end (AFE) designed for flat-panel detector (FPD)-based digital x-ray systems. It includes 256 integrators, a programmable gain amplifier (PGA), a correlated double sampler (CDS), 256:4 analog multiplexers, and four differential output drivers. The device also features four 14-bit successive-approximation register (SAR) analog-to-digital converters (ADCs). Serial data from the ADCs are available in SPI format. Hardware-selectable integration polarity allows positive or negative charge integration. The Nap feature enables substantial power saving. The AFE0256 is available as a 22-mm x 5-mm gold-bump die.

Features
256 channels
On-chip, 14-bit ADC
High performance:
Noise: 758 electronRMS (eRMS) with 28-pF sensor capacitor in 1.2-pC range
Integral nonlinearity: ±1.25 LSB with internal 14-bit ADC
Minimum scan time:
Normal mode: 37.9 us, internal ADC
2x binning mode: 26 μs, internal ADC
Integration:
Eight selectable, full-scale ranges: -0.15 pC (min) to 9.6 pC (max)
Built-in correlated double sampler
2x binning for faster throughput: averages charge of two adjacent channels
Pipelined integration and read: allows data read during integration
Flexibility:
Electron and hole integration
Analog output provided for external high-resolution ADC
Low power:
2.9 mW per channel with ADC
2.3 mW per channel without ADC
0.1 mW per channel in Nap mode
Total power-down feature
22-mm x 5-mm gold-bump die suitable for tape carrier package (TCP) or chip-on-film (COF)

Applications
Flat-panel X-ray detectors