N1_Hardware_User_Guide
Copyright © Neoway Technology Co., Ltd
38
Table 5-2
Audio output pins
Pin
Signal
I/O
Function
Remarks
136
CDC_EAR_P
AO
Positive pin of receiver output
137
CDC_EAR_M
AO
Negative pin of receiver output
151
SPKR_DRV_M
AO
Negative pin of speaker output
152
SPKR_DRV_P
AO
Positive pin of speaker output
The speaker pins support Class D amplifier and differential output. The typical speaker output power is
1.4W/0.95W@8Ω when the battery supplies 5V/4.2V, 2W/1W@4Ω when the battery supplies 5V/3.6V.
The speaker can provide overburst protection and noise rejection.
Figure 5-2 shows the reference design of the audio output pins.
Figure 5-2
Reference design of EAR/SPK connections
33 pF
33 pF
EAR/SPK-
EAR/SPK+
33 pF
N1
EAR/SPK
1800
Ω
±25%
（
@100MHz
）
1800
Ω
±25%
（
@100MHz
）
TVS
TVS
5.3 Headphone Interfaces
The module provides fixed pins to achieve the headphone function. N1supports class AB headphone
amplifier and three headphone control buttons. Table 5-3 lists the headphone pins.
Table 5-3
Headphone pins
Pin
Signal
I/O
Function
Remarks
141
CDC_HPH_L
AO
Left sound channel of the
earphone output
140
CDC_HPH_REF
Headphone output level
139
CDC_HPH_R
AO
Right sound channel of the
earphone output
143
MIC2_P
AI
Audio input of MIC2, used for
single-end headphone input
142
CDC_HS_DET
DI
Headphone detection
High level by default
