The GX1642, GX1648, and GX1649/GX1649-1 boards are 3U PXI boards. The GX1632e board is a 3U PXI Express (PXIe) board. All of these boards belong to a class of instruments which provide precision analog outputs. The boards are configured as four groups, with each group having 8 or 16 analog output channels with 12- or 16-bit resolution. The voltage range for each group can be programmed to 0-10V, ±10V, 0-5V or ±5V for the GX1642. The GX1648 can be programmed with the following values: 0-20V, ±20V, 0-10V or ±10V. The GX1649 supports single range of ±15V. Each group’s channel voltages can be set simultaneously through software or by an internal or external command signal. The GX1649 and GX1632e also include an internal memory that can be used to generate waveforms, enhancing the maximum software-based update rate when compared to the GX1642/GX1648. The GX1649-1 and GX1632e support streaming the waveform using user supplied interrupt callback.