3.3 Controllers and Processors With
Bidirectional I/O Pins
Some microcontrollers have bidirectional reset pins.
Depending on the current drive capability of the
controller pin, an indeterminate logic level may result if
there is a logic conflict. This can be avoided by adding
a 4.7 kΩ resistor in series with the output of the
TC1272A (Figure 3-3). If there are other components in
the system that require a reset signal, they should be
buffered so as not to load the reset line. If the other
components are required to follow the reset I/O of the
microcontroller, the buffer should be connected as
shown with the solid line.
To Other System
Interfacing the TC1272A to
a Bidirectional RESET I/O.
2004 Microchip Technology Inc.