The ADC’s dynamic performance of -147 dBm/Hz noise floor, 52 dB noise power ratio (NPR) and -61 dBFS intermodulation distortion (IMD) has been developed by National to enable a new generation of software-defined radio (SDR) architectures and applications.

Paul McCormack, marketing manager for National’s High-speed product group, explained: “What we are launching is a family of ultra-high speed 12-bit analog-to-digital converters (ADC).  The fastest device is capable of running sample rates up to 3.6 GSPS in single channel mode.  This is actually giving us a leadership position in the market with the fastest 12-bit devices which are 3.6 times faster than our competition. This allows you to sample the Nyquist bandwidth 3.6 times higher than what our competition can do.  This really is enabling new applications in software-defined radio (SDR) and advances in other new architectures”.

McCormack continued: “We have been developing these converters for ten years.  We have done 8-bit and 10-bit products in the past and this is an extension of that family and we are going to the next level in terms of sample speed and dynamic range.  We have pushed the limits and this is really the fastest product that you will be able to find on the market.  We are offering the highest resolution at the fastest sampling speed”.  

“Traditional architectures would have required the use of many analog building blocks featuring a lot of mixers, filters and amplifiers.  A lot of this can be replaced by having a very high-speed ADC.  The advantage here is that you reduce complexity, reduce board area and reduce power consumption while adding a lot more flexibility into the system”.


In addition to the ADC12D1800, National is also introducing two other members of its ultra high-speed ADC family: the ADC12D1600 with sampling speed up to 3.2 GSPS and the ADC12D1000 with performance up to 2.0 GSPS. All three PowerWise ADCs target wideband SDRs including radar, communications, multi-channel set-top box (STB), signal intelligence, and light detecting and ranging (LIDAR) applications.

National’s ADC12D1x00 family enables new SDR architectures to be realized thanks to its ability to accurately receive modulated, band-limited signals within a large bandwidth. For example, in military radar systems, a single ADC12D1X00 combined with a digital down-converter can replace multiple mixers, filters, amplifiers and local oscillator stages used in traditional heterodyne double- or triple-conversion radio implementations.

In next-generation multi-channel STB applications, one ADC12D1X00 can replace all of the STB’s tuners. Shifting such architectures to an SDR implementation reduces board area, power consumption, and cost, while improving system flexibility.

The new class of SDRs requires the ADC to sample wide-bandwidth signals, thereby enabling a new set of metrics such as noise-floor, NPR and IMD to provide the best measure of a system’s capability to extract narrowband information from a wideband spectrum. This contrasts with traditional ADC specifications - signal-to-noise ratio (SNR), spurious-free dynamic range (SFDR), and effective number of bits (ENOB) - which focus on single-tone performance in the Nyquist bandwidth and do not provide the best gauge of a system’s overall capability.  

Key Features of the ADC12D1x00 12-bit, Ultra High-Speed ADCs, include:

National’s 12-bit ADCs are supplied in a leaded or lead-free, 292-ball, thermally enhanced BGA package, and are pin-compatible with the ADC10D1000 and ADC10D1500 ADCs. The 12-bit ADCs run off a 1.9 V single supply and consist of two channels that can operate interleaved or as independent channels. They include circuitry for multi-chip synchronization, programmable gain and offset adjustment per channel. The internal track-and-hold amplifier and extended self-calibration scheme enable a flat response of all dynamic parameters for input frequencies exceeding 2 GHz, while providing a low 10-18 code error rate.

The ADC12D1800 provides sampling rates up to 3.6 GSPS, or dual-channel rates up to 1.8 GSPS. In addition to excellent noise floor, NPR and IMD performance, the ADC12D1800 offers 57.8 dB SNR, 67 dBc SFDR and 9.2 ENOB at 125 MHz. The energy-efficient design consumes only 2.05 W per channel.

The ADC12D1600 delivers single-channel sampling rates up to 3.2 GSPS, or dual-channel rates up to 1.6 GSPS. It features a -147.5 dBm per Hz noise floor, 52 dB NPR and -63 dBFS IMD. The ADC12D1600 consumes 1.9W per channel and offers 58.6 dB SNR, 68 dBc SFDR and 9.3 ENOB at 125 MHz.

The ADC12D1000 provides single-channel sampling rates up to 2.0 GSPS, or dual-channel rates up to 1.0 GSPS. The device features a -147.5 dBm per Hz noise floor, 52 dB NPR and -66 dBFS IMD. The ADC12D1000 consumes 1.7 W per channel and offers 59.1 dB SNR, 70.5 dBc SFDR and 9.5 ENOB at 125 MHz.

A space-qualified version of the ADC12D1x00 will be supplied in a hermetic 376 column, ceramic column grid array (CCGA) package that meets radiation levels of 120 MeV for single event latch-up and a total ionizing dose of 100 Krads (Si).
The device is pin-compatible with the ADC10D1000QML 10-bit ADC.

Availability and Pricing

All three ADCs are sampling now, with production quantities available in the third quarter of 2010.

Non-flight prototyping units and evaluation boards in the CCGA package will be available in the third quarter of 2010.

Related links:

ADC12D1800

ADC12D1600

ADC12D1000