A data network may include a data bus and network nodes. The data bus may be a differential data bus having first and second differential signal lines that convey differential signals between the nodes. A bimodal impedance terminator may be coupled to the first and second differential signal lines at one or both ends of the data bus. The bimodal impedance terminator may include a first resistor coupled between the first differential signal line and a circuit node and a second resistor coupled between the second differential signal line and the circuit node. A capacitor may be coupled between the circuit node and ground. A third resistor may be coupled between the circuit node and ground in series with the capacitor. The bimodal impedance terminator may terminate both the differential-mode impedance and the common-mode impedance of the data bus to reduce signal reflections at the ends of the data bus.