User's Manual

Telit TRIZIUM Product Description
80264ST10007a Rev. 4– 09/09/04
Reproduction forbidden without DAI Telecom written authorization – All Right reserved – Right of modification reserved page 17 of 202
The minimum duration of a DTMF tone is 100 ms.
Group high
Group low
1209 Hz 1336 Hz 1477 Hz
697 Hz 1 2 3
770 Hz 4 5 6
852 Hz 7 8 9
941 Hz * 0 #
2.11.17 Buzzer output
The General Purpose I/O pin GPIO7 can be configured to output the BUZZER output signal, with only an external
Mosfet/transistor and a diode a Buzzer can be directly driven.
The ringing tone and the other signaling tones can be redirected to this Buzzer output with a specific AT command.
2.12 Logic level specifications
Where not specifically stated, all the interface circuits work at 2.8V CMOS logic levels.
The following table shows the logic level specifications used in the Telit TRIZIUM module interface circuits:
Absolute Maximum Ratings -Not Functional
Parameter Min Max
Input level on any digital
pin when on
-0.3V +3.75V
Input voltage on analog
pins when on
-0.3V +3.0 V
Operating Range - Interface levels (2.8V CMOS)
Level Min Max
Input high level 2.1V 3.3V
Input low level 0V 0.5V
Output high level 2.2V 3.0V
Output low level 0V 0.35V
For 2,0V signals:
Operating Range - Interface levels (2.0V CMOS)
Level Min Max
Input high level 1.6V 3.3V
Input low level 0V 0.4V
Output high level 1,65V 2.2V
Output low level 0V 0.35V