acquisitionZONE Products for the week of June 30, 2003
TelASIC Communications, developer of RF, analog mixed signal, and digital ICs for advanced wireless applications, announced the availability of the TC2401, the industry's highest-performance 14-bit, 1 Giga Sample per Second (GSPS) digital-to-analog converter (DAC). This industry-leading DAC delivers very high resolution at update rates currently not commercially available in the market, which will allow a variety of advanced wireless implementations to reach new levels of performance. Based on IBM's silicon germanium (SiGe) process technology, the TC2401 delivers these exceptional performance characteristics at high frequencies while still meeting stringent noise metrics.
"We are very proud to take the market lead with the delivery of our first DAC," said Tony Giraudo, TelASIC's president and CEO. "This level of performance is indicative of TelASIC's technical expertise, and will be the standard to which all future TelASIC products will be held."
The high speed and high resolution capabilities of the TC2401 greatly simplify transmitter design. System designers are able to specify DAC clock rates up to 1GHz, allowing higher intermediate frequency (IF) signals. This eliminates an additional up-conversion stage by pushing images generated through the mixing process further away from the bandwidth of interest. In addition to comprehensive performance gains, the overall system design is simplified, resulting in lower costs due to reduced component count.
Delivering world-class performance, the TC2401 provides 70dBc of spurious-free dynamic range (SFDR) when clocked at a frequency of 1GHz with an output frequency of 125MHz and measuring SFDR over the entire Nyquist (fclk/2) bandwidth. At higher output frequencies, the TC2401 continues to deliver high levels of performance. When updating at the same 1GHz rate and with a single-tone output at 490MHz, the TC2401 delivers 66dBc of SFDR performance.
Offering a low-voltage differential signal (LVDS) interface, the TC2401 maintains high signal integrity in the data and clock interfaces at high data rates without generating excessive switching transients. This is in contrast to traditional DACs that use standard TTL or CMOS interfaces, which are notorious for being a source of performance limitation for high SFDR applications.
In addition to transmitter implementations, many other applications will
benefit from the TC2401's superior performance, including automated test
equipment (ATE) for arbitrary waveform generators, lab test equipment for
signal generation, local oscillators in both wireless and wireline communications
equipment, cellular base station equipment, multi-carrier power amplifiers
(MCPA) and direct digital synthesizer (DDS) applications.
analogZONE Says . . .
A new company name to me, although TelASIC released a 1 Gsample/s 10-bit ADC in October 2002. The company is an extremely well-funded (VC) spin-off from Raytheon Defense and has a huge pool of talent. It is designing products to be fabricated on IBM's SiGe process.
When Triquint and SPT offered high-speed converters they were probably ahead of their time and TQS is now out of the business and SPT was bought by Fairchild Semiconductor with 400 MHz being their fastest DAC. The opportunities for 1 GHz and higher conversion rates are now increasingly coming with not only communications transmission infrastructures but also in instrumentation, medical scanning and low-frequency radar systems. Companies like Maxim have chosen to go for higher resolution with lower speeds (so far) than offered here by TelASIC (MAX5888 is a 16-bit 500 Msample/s part) and it is difficult to guage which direction the market will turn in first.
The TC2401 quotes its power dissipation at <3 W with ±5 V rails which seems rather high - I would have expected about 1 W, extrapolated from other products - while the dual rail is unfortunate. SFDRs are superb at both the quoted 720 MHz clock and 1 GHz clock but I would like to see the numbers for a 10 MHz output (which is generally lower) to be able to compare better with other products. There are no numbers in the preliminary data sheet for IMD or ACLR, while SNR (or is it really SINAD?) quoted at a tantalizing 71 dB with a 480 MHz clock.
LVDS is the obvious way to go for the input to these high-speed products and the output is a usable 50-ohm differential (no return loss quoted.) An internal band-gap reference provides 2.5 V.
Being first on the block has advantages and disadvantages. Falling back on its corporate links is a good positioning for the company to attach a high-reliabilty tag to its products, but we need to see a more complete data sheet to get sockets won. The company is not discussing price of the TC2401 but it will have to be in the $35 range (1000-piece lots) to attract maximum attention.
The TC2401 is sampling (limited) in a 19 x 19 mm BGA-96.