This application note investigates the possibility of using a TDE1708DFT switch for the physical layer transmitter realization of 3-wire IO-Link sensors. The TDE1708DFT is an integrated power switch especially dedicated to proximity detectors. It can deliver up to 250 mA, enables high-side and low-side configurations and includes a number of protections. According to the IO-Link Communication Specification (see Section 8: References -3. and for the TDE1708DFT features - see Section 8: References - 1.) two basic slave transmitter configurations were tested (see Figure 1): p-switching (high-side) driver p-switching driver with an additional n-switching (low-side) driver (push-pull operation). Figure 1. P-switching slave drive and p-switching with n-switching slave drive In the following test arrangements the input load current (ILLM) is fixed to 10 mA which represents the average master current sink value specified for a 3-wire system. The master (CQM), slave (CQL), and line capacitances are set together at 4.7 nF, corresponding to the maximum parasitic capacitance of the system.