16-bit, 210 Msps ADC brings 80dB SNR to comms and instrumentation

April 30, 2014 // By EDN
LTC2107 is a 16-bit, 210 Msample/sec high performance high-speed analogue-to-digital converter (ADC) for high-end communications receivers and instrumentation applications.

It has superior AC performance specifications, achieving 80 dB SNR performance, 4 dB higher than alternative products, and 98 dB SFDR at baseband. Exceptional aperture jitter of only 45 fsecRMS enables direct sampling of frequencies up to 500 MHz with excellent SNR performance.

The LTC2107’s features simplify receiver design and improve system performance. An optional internal transparent dither circuit improves the ADC’s SFDR response well beyond 100 dBfs for low level input signals. A digital output randomiser and alternate bit polarity mode dramatically reduce unwanted tones caused by digital feedback. The flexible digital outputs can run as full-rate CMOS for sample rates below 100 Msamples/sec, or double data rate (DDR) LVDS to minimise routing of lines to an FPGA.

The LTC2107 also features a programmable gain amplifier (PGA) front end that sets the ADC input range to either 2.4Vp-p or 1.6Vp-p; this gives you the flexibility to trade off between noise and distortion. The best distortion performance is achieved in the 1.6Vp-p range while the 2.4Vp-p range results in the best noise performance. The LTC2107 occupies a 7 x 7 mm QFN package, and dissipates 1.3W without the need for heat sinking. It runs from a single 2.5V analogue supply and comes with a clock duty cycle stabiliser for maintaining the ADC’s performance over varying duty cycles. The LTC2107 can accept high frequency, wide dynamic range signals, offering a wide analogue input bandwidth of 800 MHz.

The LTC2107 costs $99.00 (1,000); demo boards are available.

Linear Technology; www.linear.com/product/LTC2107