Dtx: Digital Input/Output (Wiegand, 1-Wire) - Sferalabs Iono Pi Max v2 3+ Lite User Manual

NOTICE
The OCx outputs can operate with positive voltage levels up to 50Vdc. Applying out of
range voltages could damage the product and connected devices.
NOTICE
Open circuit fault detection is implemented in the MAX4896 by a pulldown current source,
along with a voltage comparator, which keeps a small current flowing when the contact is
open. This might interfere with the proper functioning of the connected device. This feature
can be disabled for all open collectors and relays using the digital_out/pdc sysfs file (I2C
control register 137).

DTx: Digital input/output (Wiegand, 1-Wire)

DTx are four bidirectional TTL-level I/O lines (0÷5V), connected to the Compute Module
GPIO pins through bidirectional level shifters. They can be used as general purpose
bidirectional data lines, as 1-Wire bus lines, or as couples of DATA0/DATA1 lines of up to
two Wiegand interfaces.
Each DTx front-end circuit has a 10.0kOhm pull-up and 220Ohm series resistors, and is
protected from over-voltage and electrostatic discharge.
NOTICE
Never apply voltages outside the 0-5V range to this pin to avoid damage to the Iono Pi
Max and Raspberry Pi Compute Module.
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TTL LEVEL CONVERTER CIRCUIT AND PROTECTION
Iono Pi Max User Guide