Technical information

Chapter 2: Hardware Interface Description
November 15, 2008 G24-L Module Hardware Description 31
Alert Loudspeaker Port
The alert loudspeaker is the default G24-L power-up ringer. It is used for, but not limited to,
sounding the G24-L alerts, melodies, and rings. It is located at pins 63 and 65 on the G24-L
interface connector, named ALRT_N and ALRT_P respectively.
It is designed with an internal amplifier supplied directly from VCC, which supplies 0.5W to the
audio device. It may also be used as a single-ended output referenced to the G24-L analog
ground.
Figure 2-19 shows the alert loudspeaker circuit and Table 2-9 gives the loudspeaker
specifications.
Figure 2-19: Differential Loudspeaker Circuit
Important: For safety regulations it is important to place series resistors on the alert output
lines, as illustrated in Figure 2-19. The resistors value should be R = 0
Ω at the
design stage, but may be changed to a different value during audio safety testing, in
case that alert level limitation is required.
Figure 2-20: SIngle-ended Loudspeaker Circuit