The Input/Output Pins (I/O PINS) are for receiving external signals and sending signals out. These general purpose I/Os (GPIOs), can be configured as Analog IO or Digital IO with the exception of PIN2, PIN6, and PIN7. PIN2 can only serve as a digital input or external reset. Pins 6 and 7 are configured as Open Drain NMOS for I2C. PIN6 and PIN7 have no PMOS structure and cannot be configured as a push-pull output.

Activation


Set ‘I/O selection’ to a GPIO mode that is not ‘Pin not Used’.
Alternatively, drag a wire to or from the PIN and a signal.
For Digital Input/Output signals, connect the OE pin to a I/O control signal.

Parameters


I/O selection:

Select PIN mode to Digital IO or Analog IO.

Pin not used: will default the PIN with a 1MΩ Pull down resistor

Digital input: OE = 0. See following Digital Input Types.

Analog input/output

Digital output: OE = 1. See following Digital Output Types.

Digital input/output: OE = 0 or 1. See following Digital Input and Digital Output Types.


Input mode OE=0:

Only available for Digital Input or Digital Input/Output modes. The Schmitt Trigger configures the PIN to have hysteresis which rejects fast and spurious signal transitions.

Digital in without Schmitt trigger

Digital in with Schmitt trigger

Low voltage digital input: the voltage threshold which determines HIGH from LOW is lower than in regular Digital input mode. No Schmitt Trigger.


Output mode OE=1:

Available for Digital Output or Digital Input/Output modes.

1x push pull

2x push pull

1x open drain NMOS

2x open drain NMOS

1x open drain PMOS

2x open drain PMOS


Resistor:

Available for both Digital Input and Digital Output modes. All ports are in Hi-Z state until chip is powered up.

Pull down resistor: Default low

Pull up resistor: Default high

Floating: no resistor


Resistor value:

If a Pull up or Pull down resistor is set for ‘Resistor’, select one of the following resistor values.

10k strongest pull up/down

100k medium pull up/down

1M weakest pull up/down


Information


Electrical Specifications

V_IH is the input voltage at digital signal transitions from a low to high.
V_IL is the input voltage at digital signal transitions from a high to low.
V_OH is the output voltage at digital high.
V_OL is the output voltage at digital low.
I_OH is the output current at digital high.
I_OL is the output current at digital low.