The National Instruments part number 778725-01 refers to the PXI-6651 PXI Synchronization Module, an essential component designed for use within PXI chassis to enable synchronization across various PXI systems. This module leverages the PXI standard's trigger bus, star trigger, and system reference clock features to achieve advanced synchronization capabilities among multiple devices or chassis. The CLKIN input boasts a nominal impedance of 50 Ω with AC coupling, supporting input voltage ranges from 400 mVPP to 5 VPP, and an absolute maximum input voltage of 6 VPP. The PXI-6651 is equipped to handle Phase-Locked Loop (PLL) applications with an uncompensated CLKIN to PXI CLKIN delay typically between 14 ns and 14.7 ns, and a maximum PLL compensated delay of ±1 ns. Additionally, this module includes general purpose PFI lines with operational frequencies from DC to 105 MHz, maintaining a nominal input and output impedance of 50 Ω.

In terms of power requirements, the module operates at a maximum of 2 A at +5 V, 600 mA at +3.3 V, 500 mA at +12 V, and 0 A at -12 V. The physical dimensions are 10 cm by 16 cm (3.9 in. by 6.3 in.), and it is designed to fit into PXI Slot 2. The front panel features an SMB male connector and two tricolor LEDs for status indication. The operational temperature range is between 0 to 55 degrees Celsius, with storage conditions from -20 to 70 degrees Celsius. It supports a relative humidity of 10% to 90% RH, noncondensing during operation and 5% to 95% RH, noncondensing during storage.

Designed for robust performance, the PXI-6651 withstands operational shocks of 30 g peak (half-sine, 11 ms pulse) and exhibits random vibration resilience with ratings of 0.3 grms from 5 to 500 Hz during operation and 2.4 grms under non-operating conditions. This module adheres to various safety standards, ensuring reliable and accurate performance in demanding industrial automation environments.