DIO II - Low phase noise Digital Source/Capture


  • Multimode Digital Source/Capture module
  • Very low jitter clock generation
  • Up to 50MHz data rate in low speed mode
  • Up to 200MHz data rate in high speed mode
  • Up to 1GHz clock rate via front clock out
  • 20-bit parallel / 24-bit serial capture capability
  • 128k x 16 pattern generator (low speed mode)
  • Programmable clock delays (high sp. mode)
  • Programmable IO levels
  • Exclusively for ATX series hardware platform

The DIO-II module is a multimode digital source and capture unit. In Low Speed Mode it provides a 20-bit parallel or 24-bit serial I/O capability running at speeds up to 50MHz. In High Speed Mode, the DIO-II provides a 16-bit parallel I/O capability up to 200MHz.

In both Modes, the Clock is generated by a low jitter PLL source that is capable of generating clocks from 320kHz up to 1GHz. In low speed mode the maximum usable clock frequency is 100MHz, in High Speed mode the maximum clock frequency via the backplane is 600MHz and via the front clock 1GHz.

The DIO-II supports external clocking (in or out), external trigger and frequency synchronization with an external reference source.

The DIO-II offers 8 Pattern Bits to the user for DUT synchronization and control. The remaining 8 Pattern Bits are used for control and synchronization of the analog source and capture modules through the ATX backplane.

The flexible pattern bit structure enables the implementation of various serial protocols as SPI, I2C, I2S, etc.

TThis ensures coherent mixed-signal measurements thereby improving the accuracy of your measurement without need for "post-process" windowing.


Pattern bit example programming



Low Speed Mode

Pattern Generator 100MHz, 128kwords x 16-bits
Data I/O Pins 20-bit parallel / 24-bit serial
Data I/O Formats parallel, byte-by-byte, serial
Source/Capture Depth 4M-words x 24-bits/8M-words x 16 bits
Internal clock frequency 320kHz to 100MHz
External clock frequency DC to 100MHz
Data source/capture rate DC to 50MHz
I/O Levels VIL: 0.4V(max), VIH: 1.2V, 1.8-3.3V

High Speed Mode

Data I/O Pins 16-bit
Data I/O Formats parallel
Source/Capture Depth 8M-words x 16-bits
Backplane clock frequency 320Hz to 600MHz
Data source/capture rate DC to 200MHz
I/O Levels LVDS
Separate Stimulus clock, Capture clock and DUT clock. All derived from the same low jitter main clock

Front panel clocks

Clock output level (typical) 1.5Vpp / 50Ω
Clock output frequency 320kHz - 1GHz
Clock input Low Speed mode DC - 100MHz
Clock input High Speed mode 1MHz - 400MHz (ref. clock in)
Clock input threshold / imp. 0V or 1V (programmable) / 50Ω


Clock jitter (typical@100MHz) 190fs
Independent delay per clock 0-32ns (~0.5ns resolution)
Trigger input threshold level 1V (1kΩ)
Pattern bit trigger capability DC - 5MHz