X3-2M Data Acquisition Board with 12 simultaneous channels of 10 MSPS 16-bit A/D, and 1.8M FPGA with DSP
The X3-2M is an XMC IO module that can be fitted in a PC using a XMC to PCIe adapter or XMC to PCI adapter or a CompactPCI chassis using a XMC to CompactPCI adapter or a Standalone PC. Other hosting options include a standalone eInstrument and connection to a variety of PC hosts.
The data acquisition board has 12 channels of simultaneous 16 bit analogue to digital converters. The maximum sample rate that can be streamed to the host is 9MSPS all 12 channels. The analogue inputs have a lowpass filter with cutoff at 25MHz, and an input range of +/-2V. The converter (AD7626) is a pipelined successive approximation device.
The converters have a maximum conversion rate of 10MSPS but the interface to the onboard memory can only sustain ~220MB/s in and out functioning as a FIFO to the host. Therefore the converters can only be run above 9MSPS if a) only 10 channels or less are used, or b) if user logic is inserted to the data flow before the memory interface which decimates the data. For example a digital downconverter.
The X3-2M has an onboard PLL which can be driven by an onboard reference oscillator or by an offboard reference clock. Alternately the user can supply an external clock. Triggering of the start of samples can be done by software or an external active high LVTTL signal.
The X3-2M also has 44 bits of user digital IO. This can be read or written to as a 32 bit register from the host, or if the user modifies the logic, can be used to interface to a variety of digital devices such as serial, parallel ports, I2C devices etc. The Spartan3 device supports LVTTL.
Data acquisition control, signal processing, buffering, and system interface functions are implemented in a Xilinx Spartan3A DSP FPGA, 1.8M gate device. Two 512Kx32 memory devices are used for data buffering and FPGA computing memory. The data acquisition board has a four lane PCI Express interface to the host which can sustain 220MB/s to the host.
The X3-2M is supported by Malibu, a set of C++ libraries to use the board under Windows and Linux. This includes example programs to use the board to setup the logic, acquire samples and stream them to disk.
The logic can be fully customized using VHDL and MATLAB using the FrameWork Logic toolset. The MATLAB BSP supports real-time hardware-in-the-loop development using the graphical, block diagram Simulink environment with Xilinx System Generator.
