HMC760Recommended for New Designs
The HMC760LC4B is a SiGe monolithic, fully differential, single rank, track-and-hold (T/H) that provides unprecedented bandwidth and dynamic-range performance...
Datasheet HMC760 on Analog.com
HMCAD1520Production
The HMCAD1520 is a versatile high performance low power analog-to-digital converter (ADC), with interleaving High Speed Modes to increase sampling rate...
Datasheet HMCAD1520 on Analog.com
AD7357Production
The AD7357 is a dual, 14-bit, high speed, low power, successive approximation ADC that operates from a single 2.5 V power supply and features throughput...
Datasheet AD7357 on Analog.com
mason100 - Moved from ADC Drivers to Differential Amplifiers and ADC Drivers. Post date updated from Saturday, May 14, 2016 8:08 AM UTC to Thursday, July 25, 2024 8:42 PM UTC to reflect the move.
As i know HMCAD1520 has 700 MHz BW at 500 MPSP 12 bit and 650 MHz BW at 1000 MPSP 8 bit. So if i have 5 GHz track and hold amplifier before ADC do i can make sampling up to 5 GHz signal at equivalent sampling time?
HMCAD can support 160MPSP to 1000MSPS. You can sample signals with instantenous bandwidth smaller than 500MHz with 8bit resolution or smaller bandwidth signals with higher bit precision.
Although several high speed ADCs offer enhanced sample rates, few of them offer input bandwidth beyond a few GHz. In addition, maintenance of good sampling linearity at frequencies above the UHF band is technologically challenging and most current ADCs suffer rapidly degrading linearity above 1 or 2 GHz signal frequency. These limitations result from the Track-and-Hold Amplifier inside ADCs which sample the input signal at a precise time instant and holds the value of the sample constant during the analog-to-digital conversion. This THA is often not optimized for ultra wideband operation.
These limitations can be overcome by using external wideband Track-and-Hold Amplifier, which is designed for use in microwave data conversion applications requiring maximum sampling rate, low noise and high linearity over a wide bandwidth. They are used as an external master sampler at the front end of an ADC. Once extended bandwidth sampling takes place within the HMC760, the low bandwidth held output waveform can be processed by an ADC with substantially reduced bandwidth. ADC converter linearity limitations at high input frequencies are also mitigated because the settled THA waveform is processed with the optimal low frequency linearity of the ADC.
The result is an extension in input bandwidth, substantial improvement in high frequency linearity and improved high frequency S/N ratio for the THA-ADC assembly compared to the performance of the ADC alone.
Regarding your question, with HMC760 and HMCAD1520 paired, you can sample signals up to 5GHz, with 1000/640/105 MSPS specified by your ADC using correct anti-aliasing filter.
But I am still have a problem. When i'm sampling at equivalent random time, cant get good rise time from ADC. At HMC760 input i have fast rise time square signal less then 100ps 10%-90%. At ADC output i never cant get what have at HMC760 input . What acquisition time is for ADC internal THA? Between HMC760 and HMCAD1520 i use diff amp ADL5565.
