Track-and-Hold Amplifiers from Aspen Support Ultra-Wide Analogue Bandwidth

The primary advantage of this design is obviating the need to down-convert the incoming analogue signal to below 1GHz before input to a broadband analogue-to-digital converter (ADC). Consequently, engineers can reduce component count considerably over traditional high frequency heterodyne receiver data acquisition architectures, by using an Inphi GigaTrack track-and-hold amplifier coupled with a high sample rate ADC. In particular, this enables a flexible design approach with software-defined receivers. The end result is a simpler, faster design with lower overall costs, allowing delivery of differentiated, high performance systems.

Designed specifically for high performance, high speed telecommunications and instrumentation applications, in civil and military systems, the GigaTrack family consists of four track-and-hold amplifiers with 2GS/s sample rates operating at 13GHz or 18GHz with or without a clock mode select feature.

The 18GHz (small signal), 1820TH and 1821TH models come in a ball-grid-array and offer very fast settling times (better than 60ps) and low power consumption (1.3W). The 1821TH is offered in Die form. For not quite so high performance applications the 1320TH and 1321TH, 13GHz devices are available in plastic (QFN) packages. A single supply voltage (-5.2V) requirement simplifies board layout and further reduces cost.

The flexible clock mode select option provides either a single differential clock or two independent differential clock inputs for both master and slave amplifier circuits. The dual device enables lower quantisation noise within the system by increasing the hold time window to almost one full cycle of the amplifier output while providing independent adjustment of phase and frequency. Total harmonic distortion is quoted at -67dB and aperture jitter at better than 50fs, giving superior ADC signal-to-noise ratio and BER figures, ideal for highly sensitive and accurate acquisition systems.

Specific applications are expected to include very fast sampling oscilloscopes, and direct conversion receivers in radios, radar or electronic warfare systems, all of which require analogue-to-digital conversion of very high frequency signals.

The GigaTrack family supports all popular, broadband analogue-to-digital ADC devices including National’s ADC08100/81500, Atmel AT84AS003/008, ADI 9480. See them at European Microwave Week from 10th to 15th September.