14-bit 500 Msample/sec digitiser achieves 3 GBytes/sec streaming to PC

June 20, 2013 // By Graham Prophet
Strategic Test (Sweden) has released its "UltraFast" PCIe instrumentation platform, UF4e, that increases streaming bandwidth and yields higher sampling rates. Acquisition data is stored inside a 4-GByte on-board buffer and can be read out at more than 3 GByte/sec through the PCI Express x8 Gen2. The ¾ card length plug-in cards are compatible to Gen1 and Gen3 and need a PCI Express slot with 8 or 16 physical lanes.

The first model based on the new platform is the UF4e-4451-x8. This comes with comes with four channels and 500 Msample/sec synchronous sampling speed at 14 bit ADC resolution. A smaller version with two channels and 500 Msample/sec is also available. Both versions have a signal bandwidth of 250 MHz.

To optimise data storage and bus transfer, repetitive signals can be stored into separate segments using Multiple Recording mode while transferring data in parallel; a feature that is useful for radar applications. The compact UF4e card is also equipped with different acquisition modes like single-shot, streaming (FIFO), segmented (Multiple Recording), gated (Gated Sampling) or the combination of segmented acquisition of fast signals in parallel to slow continuous data recording (ABA mode). All trigger events can be time stamped. Timestamp clock can either be based on the internal clock circuit or an externally fed-in time reference signal.

The four (or two) input channels are completely separate and have one monolithic ADC per channel, as well as an individual high precision pre-amplifier. Each amplifier can be configured separately by software. Software can select one of six input ranges (±200 mV up to ±10 V), 50 Ohm or 1 MOhm input impedance and AC or DC coupling. A bandwidth filter can be activated which suppresses high frequency noise signals.

The UF4e cards have a powerful trigger engine that can combine the two external trigger inputs with channel trigger of each channel by a logical OR or AND. The channel trigger detection can be programmed for edge, level, window or pulse width. Up to eight UF4e cards can run synchronously in one system. The star-hub module option distributes clock and trigger signals between the cards. The star-hub module can combine all of the trigger sources of all connected cards making it possible to use any trigger source as a starting event for the complete system. Using the star-hub a total of 32 channels with