SBOS092B June 1998 – January 2025 XTR106
PRODUCTION DATA
The long wire lengths of current loops invite radio frequency (RF) interference. RF interference can be rectified by the sensitive input circuitry of the XTR106 causing errors. These errors generally appears as an unstable output current that varies with the position of loop supply or input wiring.
If the bridge sensor is remotely located, the interference can enter at the input terminals. For integrated transmitter assemblies with short connection to the sensor, the interference more likely comes from the current loop connections.
Bypass capacitors on the input reduce or eliminate this input interference. Figure 6-6 shows to connect these bypass capacitors to the IRET pin. Although the dc voltage at the IRET pin is not equal to 0V (at the loop supply, VPS) this circuit point can be considered the transmitter ground. The 0.01μF capacitor connected between V+ and IO can help minimize output interference.