SimCom SIM8905A User Manual page 22

SPK1P
SPK1N
Module
Table 12: speaker driver output performance specifications
Parameter
Output power (Pout)
(f = 1 kHz, gain = 12 dB,
THD+N ≤ 1%)
THD+N
(1 kHz)
Efficiency
（Vdd = 3.7 V）
output impedance
Shutdown
Turn on time
Microphone bias
SIM8905A provides two microphone bias outputs: MIC_BIAS1and MIC_BIAS2.
The microphone bias cannot be used for ECM-type microphone. MIC_BIAS1and MIC_BIAS2 could be used
for External MEMS microphone as power supply.
The microphone bias output performance specifications are shown in the following table:
Table 13: Microphone bias output performance specifications
Parameter
33pF
10pF
33pF
10pF
33pF
10pF
Route as differential pair
& shielded by GND
Figure 23: Speaker reference circuit
Test conditions
15 μH + 8 Ω + 15 μH, Vdd = 3.6 V
15 μH + 4 Ω + 15 μH, Vdd = 3.6 V
15 μH + 8 Ω + 15 μH, Vdd = 3.8 V
15 μH + 8 Ω + 15 μH, Vdd = 4.2 V
1 W Pout, VDD_SPKR = 4.2 V
800 mW Pout, VDD_SPKR = 4.2 V
600 mW Pout, VDD_SPKR = 3.8 V
500 mW Pout, VDD_SPKR = 3.6 V
500 mW Pout, 15 μH + 8 Ω + 15 μH
1 W Pout, 15 μH + 4 Ω + 15 μH
Disabled
current
Test conditions
Smart Machine Smart Decision
Close to speaker
10pF
10pF
10pF
Min
584
862
662
819
-
-
-
-
82.0
73.0
25
-
-
Min
22
ESD
33pF
33pF
ESD
33pF
Typ Max Units
631 - mW
953 - mW
710 - mW
879 - mW
-85.0 -75.0 dB
-75.0 -45.0 dB
-75.0 -70.0 dB
-76.0 -71.0 dB
84.0 - %
78.0 - %
kΩ
- -
0.1 1.0 µA
0.2 10.0 ms
Typ Max Units