User Manual

Medio L40 - User's Guide
46/56 Revision 2.3 July 2013
6.3.4 Using Outputs
The reader outputs are Open Drain, N-Channel (when activated, an output is tied to the ground).
They can drive a current up to 1.4A, and accept voltages up to 28V. Outputs are internally pulled-
up to 3.3V with 1KOhms resistors and are protected against overload and overheat. Applying
negative voltage to outputs (polarity inversion) may destroy them.
Figure 25 below demonstrates how to connect an external load to an output.
Figure 25: Connecting an external load to output #1
External devices must be connected to GPIOs in compliance with Table 8 and SELV
requirements.