IO-Link Servo Driver
Created: May 23, 2017
No description available.
Traditional pneumatic actuators have known disadvantages. Air producing equipment adds cost. Furthermore, high pressure air condenses easily, can leak and also can be very noisy. IO Link is a 24-volt, three-wire, half-duplex, point-to-point sensor and actuator communication interface. Remote configuration, diagnostics, event triggering and process data readout are made possible from a PLC via a three layer protocol stack. IO-Link can be used for simple binary sensors and smart sensors.
This reference design consists of 4 main blocks: IO-Link device transceiver, step-down converter, microcontroller, and one of four possible servo motors. This circuit provides 5V power, four PWM outputs and four digital inputs for control of up to four 5V servo motors. IO-Link offers the ability to replace pneumatic actuators, and their compressed air lines, in industrial applications. With added level translation, the digital inputs allow for interfacing to binary position or status sensors. The MAX14821 IO-Link device transceiver is IO-Link version 1.1/1.0 physical layer compliant with configurable outputs (push-pull, pnp or npn), reverse-polarity/short-circuit protection, and extensive fault monitoring. The MAX17504 is a high-voltage, synchronous step-down converter that efficiently converts 24V to 5V. The circuit defaults to PFM operation to achieve the highest efficiency during light and heavy loads. It also implements a soft-start to limit inrush current at initial power-up and an active-low RESET output that keeps the microcontroller in reset until the output voltage is stable.
This design unveils a completely new application to the industrial segment with potential to disrupt the traditional pneumatic methods used today. Onboard, standard 3-pin headers allow quick connection to off-the-shelf 5V servo motors. The circuit comes with a HiTec HS-53 servo motor. Push-in terminal blocks allow simple connection to 5V digital inputs, power, ground, and also access to all four PWM channels. The onboard rugged male M12-4 connector allows for a standard connection to any compliant IO-Link master.