Sierra Wireless WISMO218 - Manual (Page 64)

WA_DEV_W218_PTS_002 Rev 005 Page 64 of 109
Product Technical Specification &
Customer Design Guidelines
BUZZER Output
The signal BUZZER outputs a square wave at the desired tone frequency. The tone frequencies are
programmable and can be re-programmed on-the-fly to generate monophonic audio ringtones or
alert tones. The tone level can also be adjusted in 4dB steps, or it can be muted.
Features
The signal BUZZER can be used in conjunction with an external transistor/MOSFET for driving a
buzzer in order to give a maximum current of 100mA (PEAK) and an average of 40mA, depending on
application requirement.
Figure 27. BUZZER Output
Table 23. BUZZER Electrical Characteristics
Parameter Condition Minimum Typical Maximum Unit
V
OH
High impedance load 2.7 2.85 - V
Load with I
oH
= 4mA - 2.4 - V
I
PEAK
- - - 4 mA
V
OL
- - - 0.1 V
Frequency - 200 - 2500 Hz
Duty cycle - 0* - 100* %
Tone level 4 dB step -24 - 0 dB
* Be mindful of the maximum frequency and the minimum/maximum duty cycle. There is a limitation due to the
RC environment. The amplitude modulation becomes less fine when the set limits are reached.
Pin Description
Table 24. BUZZER Pin Descriptions
Signal Pin Number I/O I/O Type Description
BUZZER 34 O 2.8V Buzzer output