EMC immunity, especially immunity against inverter switching noise, is important for positioning encoder feedback systems of industrial drives. This design demonstrates a high EMC immunity RS485 transceiver solution which can be used on both the drive and encoder, such as Tamagawa™, EnDat 2.2, BiSS®, and so forth. The design supports a wide input voltage of 5 V. A connector with 3.3-V logic I/O signals and a 3.3-V power supply allows direct interface with the host processor to run the master protocol and power the processor. To meet the supply range of the selected encoder, the design offers an output voltage to the encoder equal to the Vin. This design’s power supply offers protection against overvoltage and short circuit, according to the selected encoder’s voltage range, to prevent damage during a cable short. The design has been tested for up to a 50-m cable length with the Tamagawa encoder.
查看参考设计
查看原理图/方框图
查看参考指南