User Guide

LM960 HW Design Guide

1VV0301485 Rev. 15 Page 59 of 88 2020-08-13

6.6.4.1. Using a GPIO Pin as Input

GPIO pins, when used as inputs, can be tied to a digital output of another device and

report its status, provided the device interface levels are compatible with the GPIO 1.8V

CMOS levels.

If a digital output of a device is tied to GPIO input, the pin has interface levels different

than 1.8V CMOS. It can be buffered with an open collector transistor with a 47 kΩ pull-up

resistor to 1.8V.

6.6.4.2. Using a GPIO Pin as Output

GPIO pins, when used as outputs, can drive 1.8V CMOS digital devices or compatible

hardware. When set as outputs, the pins have a push-pull output, and therefore the pull-

up resistor can be omitted.

GPIO Output Pin Equivalent Circuit

6.6.4.3. Dedicated I/O

In order to use SIMIN functions, host must use GPIO_01/GPIO_02.

Dedicated I/O

no.

Signal IO/Level Dedicated Function

3 GPIO_01 Input/1.8V Can be used as SIMIN1 function

5 GPIO_02 Input/1.8V Can be used as SIMIN2 function