X-ray readout IC offers clearer images

By Gina Roos, editor-in-chief

A new 256-channel readout IC for digital X-ray flat-panel detectors (FPDs) from ams provides clinicians with clearer images while reducing the patient’s exposure to radiation. The AS5850A digital readout IC is a 16-bit charge-to-digital converter that can be used in static and dynamic digital X-ray scanners, digital radiography, mammography, fluoroscopy, and interventional imaging.

The AS5850A provides improved performance of medical imaging equipment thanks in part to the circuit design and CMOS process used at the company’s wafer fab. In particular, the new device offers low noise as little as 500 electrons at 2 pC and 30 pF, which enables an FPD to recover clearer image outputs from a lower radiation input.

Optimized for dynamic radiography applications, the AS5850A achieves a line time of 20 µs, which can go as low as 10 µs in binned mode by combining the inputs from adjacent channels. The device has a special mode for fluoroscopy applications with relaxed noise requirements that enables a line time of 15 µs.

The programmable architecture of the AS5850A enables medical imaging equipment to base multiple end-product designs on this single device, thus reducing the development and production cost of meeting different application requirements.

The AS5850A is compatible with many FPD sizes and offers various configuration options, including speed and power settings. Selectable line time options without binning are 20 µs, 28.5 µs, 40 µs, and 80 µs. At 80 µs, power dissipation per channel is 1.1 mW.

Sampling now, the AS5850A is supplied in a chip-on-flex packaging format to minimize sidewall distances and to allow for direct assembly on the X-ray panel. The flex circuit design can be customized.

The company plans to provide the AS585x readout ICs in a variety of standard packaging formats and performance options for FPD manufacturers. Several devices with different speed and power dissipation will be released in the coming months, along with different flex designs, including the option to add a stiffener for compatibility with standard connectors.