National Instruments 779139-01 C Series Digital Module

The 779139-01 is an identifying part number for the NI‑9425 C Series Digital Module by National Instruments. With 32 channels of 24 V sinking digital inputs, this module is a high-performance solution suited for industrial automation applications. Robust connectivity and dependable performance in difficult conditions are ensured by the part's easy interface with a range of industrial switches, transducers, and devices.

Each digital input line on the 779139-01 provides isolation between the input and output banks from the channel to earth ground and is compatible with logic levels of 24 V. The module's dependability is increased and linked gadgets are safeguarded by this isolation. This device has a specific use case, as evidenced by the fact that it is incapable of performing counter operations in a CompactDAQ chassis.

The 779139-01 has a 37-pin DSUB connector that allows connections for all 32 digital input channels that are sampled simultaneously. Each channel has four common pins (COM) that are internally connected to the isolated reference of the module and one DI pin for connecting to digital input signals. Because of the sinking input architecture, when the device drives current or applies voltage to the pin, the DI pin provides a path to COM for current or voltage. In order to guarantee safe functioning, the module additionally internally restricts current signals connected to DI.

Low-power sleep mode functionality for the 779139-01 is contingent upon the chassis that it is connected to. Although system connection with the modules is normally stopped while the system is in sleep mode, it nevertheless uses less energy and produces less heat, making it a good choice for a variety of applications.

In terms of  power consumption, this module has 32 digital input channels. While it only uses 0.5 mW while it is in sleep mode, it can draw up to 410 mW from the chassis when it is operating. Very little heat is lost during operation—1.45 W during active mode and 1 W during sleep mode.

Digitized logic levels are used to run the 779139-01. It takes input voltages of up to 5 V and currents of up to 150 μA in the OFF state and up to 10 V and up to 330 μA in the ON state. Ensuring exact signal integrity, this module has a minimum input impedance of 30 kΩ ± 5%.