Fig 1. The tiny four-channel 16-bit ADS5263 ADC from Texas Instruments provides high-resolution and high-speed imaging for medical scans like MRIs, ultrasound, CT scans, and X-rays. Its mere 9- by 9-mm VQFN package footprint is one-half that of other 16-bit, four-channel ADCs on the market.
Fig 2. A version of the ADS263ADC in a non-magnetic package is available to provide clearer MRI scans (right) compared with a regular BGA package (left).
Manufacturers of medical imaging platforms are demanding better performance in smaller and more cost-effective packages. They’re seeking more compact devices that will give them crisper and clearer multiple images as well as provide greater power efficiency. These features will enable faster and more comfortable scans while leading to earlier detection and treatment of diseases, benefiting patients as well as medical providers.
With all of this in mind, Texas Instruments (TI) has leveraged its expertise in data conversion and imaging technologies with the introduction of the smallest high-speed, high-resolution analog-to-digital converter (ADC) for high-end medical imaging applications. The ADS5263 can be used in magnetic-resonance imaging (MRI), ultrasound, computerized axial tomography (CT), and X-ray applications.
The ADC is quite small with a footprint of 9 by 9 mm in a very thin-profile quad flat no-lead (VQFN) package, but it packs a punch in performance. It offers a quad-channel input, 16-bit resolution with up to 100 Msamples/s sampling and consumes just 380 mW/channel (Fig. 1). “This device offers a 50% \\[printed circuit board\\] space savings and consumes one-half the power of other 16-bit ADCs on the market,” says Veronica Marques, TI business development manager.
The ADS5263 also offers a signal-to-noise ratio (SNR) of 84.6 dB full scale at 100 Msamples/s and accepts an input of 4 V p-p. A 14-bit version is also available with an input of 2 V p-p. Each channel in the ADS5263 contains a 16-bit analog front end, a 14-bit ADC, digital signal-conditioning circuitry, and a pair of serializer circuits. The chip also integrates a clock buffer, a clock generator, a phase-locked loop (PLL), a reference, and ADC control and serial interface circuitry.
Mindful of the fact that MRI scans require very clear images, TI is providing the chip with an optional non-magnetic package for clear images in a strong magnetic field. “We’ve taken out of the package as well as the silicon magnetic materials like nickel, iron, cobalt, etc., to ensure that a very clear image is possible of an MRI scan compared to a conventional approach,” explains Marquez (Fig. 2).
The ADS5263EVM evaluation board is available with an IBIS model to verify signal-integrity requirements. Samples of the board and ADC are available now. The evaluation board costs $299.00. The regular-packaged ADS5263 without a magnetic field costs $236.50 in quantities of 1000 units. The non-magnetic package option costs $385.50 in quantities of 1000 units.
Texas Instruments Inc.
www.ti.com