DE910 Series Hardware User Guide
1vv0300951 Rev.9 – 2015-05-11
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights
Reserved. Page 53 of 77
10.1.
Logic Level Specification
Where not specifically stated, all the interface circuits work at 1.8V CMOS logic levels.
The following table shows the logic level specifications used in the DE910 interface circuits:
Absolute Maximum Ratings -Not Functional
Parameter
Min
Max
Input level on any digital pin (CMOS 1.8) with respect to ground
-0.3V
2.3V
Operating Range - Interface levels (1.8V CMOS)
Parameter
Min
Max
Input high level
1.5V
2.1V
Input low level
0.0V
0.35V
Output high level
1.35V
1.8V
Output low level
0.0V
0.45V
Current characteristics
Parameter
Typical
Output Current
2mA
Input Current
30uA
10.2.
Using a GPIO Pad as Input
The GPIO pads, when used as inputs, can be connected to a digital output of another device
and report its status, provided this device has interface levels compatible with the 1.8V
CMOS levels of the GPIO.
If the digital output of the device is connected with the GPIO input, the pad has interface
levels different from the 1.8V CMOS. It can be buffered with an open collector transistor with
a 4.7KΩ pull-up resistor to 1.8V.
