Idea for a USB-based high-speed digitizer

[Ben321]

My idea is for a high speed digitizer (similar to, but not the same as an oscilloscope). Unlike a scope, a digitizer has no circuits or firmware for triggering or other advanced oscilloscope functions. It's basically a sound-card, but at a much higher samplerate (10s of MSPS, or about 1000 times as fast as a sound-card). Accordingly it doesn't require complex software on the PC side either. All it needs is a program that runs in a small window with a start and stop button for manually starting and stopping its recording, and optionally a way of setting a recording duration for it to use to automatically stop the recording. The only other thing the software needs (and the hardware should support) is the ability to select voltage range or sensitivity of the device (basically the gain of the input amplifier). Higher gain or sensitivity means smaller voltage range. The file can either be saved directly to the harddrive or (if the harddrive isn't fast enough) store the samples in memory (recording buffer sized limited by RAM in the computer), and then save the memory-stored samples to harddrive when the recording has been stopped (either manually, or automatically when the recording has reached a set duration or the memory buffer is full). As it doesn't require triggering, or comparing 2 signals in realtime, it doesn't need more than one channel, so a digitizer can be built with one channel, a voltage amplifier, an ADC, and a USB interface. The idea is to record a signal from some source (a photodiode, a serial port, an analog video signal, etc), for later analysis. Very simple concept for hardware, and software, though no company has made one yet. The best I've seen are your multi-channel scopes, but they put too much effort into being a scope (things like triggering and multi-channel connections, having either a high sample rate or a high bitdepth but not both simultaneously), and thus lack some of the features a digitizer would have (those being simple hardware/software, and simultaneous high samplerate and high bitdepth digitization of a single channel). Also while a soundcard typically allows full use of the bandwidth of the soundcard (you have 24kHz bandwidth for a 48kSPS soundcard), most oscilloscopes don't (your scopes allow something like 80MHz bandwidth for a 200MSPS scope, and not the full 100MHz bandwidth that is actually possible). A digitizer however, would (like a soundcard) allow the full bandwidth of the device to be used. The usefulness of this is to digitize a signal from some source, for later analysis with some other 3rd-party signal analysis software.

Here's the exact specs I'm looking for in a digitizer.
one channel
DC coupled
at least 12bits bitdepth for ADC
at least 10MSPS sample rate
at least 5MHz bandwidth
high input resistance (1MOhm at a minimum, 10MOhm would be good)
simple software with few options
voltage range selectable in software

[VirtinsTech]

Thanks for the suggestions. We will consider this in our future hardware development. Using USB3 instead of USB2 will increase the streaming speed by about 10 times.