Differential Speaker Circuit; Single-Ended Speaker Circuit - Motorola 8900 - Blackberry Curve Cell Phone OEM Car Charger Developer's Manual

Audio Interface
It is designed as a differential output with 32Ω impedance, but may also be used as a single-ended
output referenced to the C24 analog ground.
The speaker output is used for both the handset and the headset audio paths.
Figure 2-17
and Table 2-8
Figure 2-17: Differential Speaker Circuit
Important:
Figure 2-18: Single-ended Speaker Circuit
28
shows a differential speaker circuit,
gives the speaker specifications.
For safety regulations it is important to place series resistors on the speaker output
lines, as illustrated in Figure
design stage, but may be changed to a different value during audio safety testing, in
case speaker level limitation is required.
C24 Module Hardware Description
Figure 2-18 shows a single-ended speaker circuit
2-17. The resistors value should be R = 0 at the
Ω
December 15, 2008