User Guide

PAMS Technical Documentation 3 - Audio System
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Buzzer driver specifications
Parameter Variable Min Typ Max Unit
Output switch resistance Rbuzzo 1.0 2.7 4.5 Ohm
Output peak sink current Iout VBAT 120 180 350 mA
Output peak sink voltage Uout VBAT 0.5 1.2 V
Output pwm duty cycle Pdcyc 50 %
Buzzer coil resistance Rload 13 16 19 Ohm
Battery voltage VBAT Ni or Li battery 3.03 3.6 5.2 (Ni)
4.2 (Li)
V
Reverse diode peak current Iforw tp = 10 us 0.35 A
Output frequency Fout, GSM system 0.48 2500 7751 Hz
UEM
BUZZPWM
5kOhm
+/- 35%
VBATDriv
BUZZO
12 pF
BUZZER
VSADriv2
1 uF
VBAT
Figure 13. Buzzer driver circuit.
)1
)/2/((
21
+= BuzzFreqRFF
BuzzClkout