The TIOL221 has an IO-Link compatible channel (CQ), a digital output driver (DO) and a digital input (DI) interface. The drivers at CQ and DO can be used in either push-pull, high-side driver (PNP), or low-side driver (NPN) configuration using the CS/PP and SDI/NPN pins in the pin-mode or via the serial peripheral interface (SPI). The internal receiver on the CQ line converts the 24V signal to standard logic levels on the receiver data output pin, RX1. Similarly, the internal receiver on the DI line converts the 24V signal to standard logic levels on the receiver data output pin, RX2. A simple parallel interface is used to receive/transmit data and status information between the device and the local controller.

The device can be configured by using the pins via pin-mode (when SPI/PIN is tied low) or using the SPI (when SPI/PIN is tied high). By using the SPI, the microcontroller can read additional diagnostics and status information as well as configure the device.

The device has integrated IEC 61000-4-4/5 EFT and surge protection. In addition, tolerance to ±70V transients enables flexibility to choose from a wider range of TVS diodes if an application requires higher levels of protection. These integrated robustness features simplify the system level design by reducing external protection circuitry.

TIOL221 transceiver implements protection features for overcurrent, overvoltage and over-temperature conditions. The device also provides a current-limit setting on the driver output current using an external resistor.

The device derives the low-voltage supply from the IO-Link LP voltage (24V nominal) via an internal linear regulator to provide power to the local controller and sensor circuitry.

Figure 1-2 TIOL221 Functional Block Diagram