ON Semiconducotr : Efficient new KNX transceivers boost power available for external loads (NCN5110, NCN5121 and NCN5130)


NCN5130: can supply up to 40mA to an LCD panel

ON Semiconductor has introduced three new certified KNX twisted-pair transceivers for use in smart building-control systems, for which KNX is the most widely adopted standard. The new transceivers offer increased regulator current and boost overall efficiency by as much as 20% compared to existing solutions.

The NCN5110, NCN5121 and NCN5130 integrate two high-efficiency DC-DC converters and a 20V low drop-out regulator for powering external loads from the bus.

The NCN5121 and NCN5130 implement the complete KNX physical (PHy) and media-access (MAC) layers; the NCN5110 is an analogue-only bit transceiver to be used in combination with a microcontroller hosting the KNX MAC.

The NCN5121 is pin-to-pin compatible with ON Semiconductor’s NCN5120, whilst offering higher efficiency and regulator output. The NCN5130 is capable of drawing up to 40mA from the KNX bus, giving designers greater flexibility to power devices such as an LCD panel or touchscreen from the communications network, or for driving relays at higher speeds.

The new devices also allow designers to specify lower external capacitance and inductance values, enabling the use of smaller supporting components. The NCN51xx devices are offered in a QFN-40 package and are specified for operation over the extended temperature range of -40°C to 105°C.


  • KNX communication speed of 9,600 baud
  • Supervision of KNX bus voltage
  • Control and monitoring of the DC-DC converters
  • Buffering of sent data frames
  • Optional auto-acknowledge


  • Home appliances
  • Home and building automation
  • Smart lighting and switches
  • Ventilation and air-conditioning
  • Thermostats
  • Alarms and smoke detectors


Evaluation board contains a KNX transceiver which handles the transmission and reception of data on the bus. It will also generate all necessary voltages to power the board and external loads. The board assures safe coupling to and decoupling from the KNX bus.

Orderable Part Number: NCN51XX10GEVB