Texas Instruments AFE2256 256-Ch Analog Front End (AFE)

Texas Instruments AFE2256 256-Ch Analog Front End (AFE) meets the requirements for a flat-panel detector (FPD)-based digital x-ray system. The AFE2256 comprises 256 integrators, a programmable gain amplifier (PGA), a correlated double sampler (CDS) with dual banking, and 256:4 analog multiplexers. Additionally, the device includes four 16-bit successive approximation register (SAR) analog-to-digital converters (ADCs). The ADC serial data is available in low-voltage differential signaling (LVDS) format. Power saving features, including nap and power-down modes, enable substantial power saving, especially useful in battery-powered systems.

Features

256 Channels
On-chip, 16-bit ADC
Photodiode short immunity
Low power consumption
Nap and total power-down mode
High performance
- Noise of 750 electrons RMS (1.2pC Input charge range)
- Low correlated noise
- Integral nonlinearity of ±2LSB with internal 16-bit ADC
- Scan time of <20µs to 204.8µs
Simple power-supply scheme
- AVDD1 = 1.85V
- AVDD2 = 3.3V

Integration
- Six selectable, full-scale input ranges at 0.6pC (min) to 9.6pC (max)
- Internal Timing Generator (TG)
- Built-in correlated double sampler
- Pipelined integration and read for improved throughput allows data read during integration
- Serial LVDS output
- Custom Chip-On-Film (COF) packages