Deep Digitizer Memory to Enhance Digitizer System Performance

Digitizer memory can be used in many ways to greatly enhance the digitizer system's performance. The size of onboard digitizer memory is one of the most important specifications for users interested in real-time data capture, streaming, or triggered event capture.

In general, onboard digitizer memory can be used in 3 ways:

  1. For real-time storage of continuous gap-free waveforms (see Table 1 below for data recording times versus sample rates for various digitizer memory sizes).
  2. The digitizer memory is segmented, and then used to store waveforms acquired at extremely fast trigger rates, (i.e. say, 500 kHz trigger rates).
  3. The digitizer memory is used as a large first in, first out (FIFO) buffer for streaming data in real-time to the PC. In this case, the large digitizer memory allows for asynchronous data collection by the digitizer, and post processing by the PC. The large digitizer memory allows for PC OS interruptions, so that the PC does not need to synchronize actions with the digitizer. The multi-GS (GigaSample) buffer allows for intense PC post processing delays by graphics, LAN, storage drives, and other operations.

Most importantly, deep digitizer memory provides real-time, multi-channel synchronized data recording capability, in a way that can't be done by other means, due to high speed multi-GS/s sample rates. In all 3 cases above, the more digitizer memory, the better.

GaGe PCI Express (PCIe) Digitizers lead the data acquisition industry for onboard digitizer memory capacity. GaGe PCIe digitizers have both the largest standard size onboard digitizer memory, and the greatest optional onboard digitizer memory upgrade capacities available from any digitizer supplier:

The Cobra and CobraMax Express CompuScope 8-bit PCIe Digitizers feature:

  • 2 GS (2 GB) of onboard digitizer memory standard
  • 4 GS (4 GB) , 8 GS (8 GB), and 16 GS (16 GB) of onboard digitizer memory upgrade options

The Oscar, Octopus and Octave Express CompuScope 14-bit / 16-bit PCIe Digitizers feature:

  • 2 GS (4 GB) of onboard digitizer memory standard
  • 4 GS (8 GB) and 8 GS (16 GB) of onboard digitizer memory upgrade options

The Razor Express CompuScope 12-bit / 14-bit / 16-bit PCIe Digitizers feature:

  • 4 GS (8 GB) of onboard digitizer memory standard
  • 8 GS (16 GB) of onboard digitizer memory upgrade options

The EON Express CompuScope 12-bit PCIe Digitizers feature:

  • 2 GS (4 GB) of onboard digitizer memory standard
  • 4 GS (8 GB) of onboard digitizer memory upgrade options

16 GS of onboard digitizer memory for 8-bit resolution sampling, and 8 GS of onboard digitizer memory for 12-bit / 14-bit / 16-bit resolution sampling leads the world today in total memory depth for PCIe digitizers.

Using the GaGe Cobra Express PCIe Digitizer for example, this would allow for 16 seconds of single channel 8-bit real-time recording at 1 GS/s (Table 1, below), without using large disk arrays, or transferring any data in real-time to the computer.


Table 1 - Recording time versus digitizer memory capacity for various sample rates

  Sample Rate
  4 GS/s 2 GS/s 1 GS/s 500 MS/s 200 MS/s 100 MS/s
Digitizer Memory Memory Recording Time (seconds)
16 GS 4 8 16 32 80 160
8 GS 2 4 8 16 40 80
4 GS 1 2 4 8 20 40
2 GS 0.5 1 2 4 10 20
256 MS 0.062 0.125 0.25 0.5 1.25 2.5
16 MS 0.004 0.008 0.015 0.031 0.08 0.15

This large amount of digitizer onboard recording memory can now be used effectively with Windows 64-bit OS that allow complimentary large memory in the PC for data offloading, post processing, and storage.

Plus GaGe turnkey PC oscilloscope software, GaGeScope, fully supports post processing from the maximum optional digitizer memory configurations. This allows turnkey, multi-channel scope like systems to be built with no programming required.

So, how does GaGe onboard digitizer memory stack up to the competition? We recently surveyed and summarized an onboard memory comparison of GaGe PCIe Digitizers to other digitizer suppliers, for models in the same approximate sample rate and performance ranges. The results are shown in Figure 1 and Figure 2 below.


Figure 1 - Comparison of base model, standard digitizer memory for 6 competitive models

Chart Comparison of Onboard Standard Size Model Digitizer Memory

For the same price or less, GaGe provides at least 8 times more digitizer memory in the base or standard configuration for the PCIe digitizer products, 2 GS versus competitors 256 MS. Many digitizer suppliers only provide 16 MS, or less in the base configuration.


Figure 2 - Comparison of maximum available digitizer memory for 6 competitive models

Chart Comparison of Onboard Maximum Size Model Digitizer Memory

For maximum optional digitizer memory, the 16 GS provided by the GaGe 8-bit PCIe digitizer is again 4 times larger than any other digitizer supplier's capability. It is currently the largest high speed digitizer memory available from any scope or digitizer supplier. And it is surprisingly low priced as compared to the price charged for additional memory on other competing digitizer products.

We encourage you to do your own comparison for the best PCIe digitizer value based on performance, specifications, and features. We’re confident you’ll choose GaGe.


High-Speed Digitizers / Oscilloscopes

GaGe high-performance digitizers are renowned for sustaining the maximum effective number of bits (ENOB) over a wide signal frequency range with quality signal conditioning and signal fidelity features.

High-Speed Digitizers High-Speed Digitizers

With sampling rates up to 6.0 GS/s and very deep onboard acquisition memory of up to 16 GB, our high speed PCIe and PCI digitizers provide optimal combinations of high sampling speeds with 8-bit, 12-bit, 14-bit, and 16-bit high resolution rates with large sampling memory options and high-speed data streaming capabilities.