ZTE Corporation MG2636 Manuale Utente

 

                                                                        MG2636 module 

                                                                                                     

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Figure 4-2 SIM Card Circuit Reference Design Diagram     

 

Note: The clock data rate of UIM card circuit is 4M, and the card socket should be laid closely around the 
module and the wiring should be as short and thick as possible. 

The module provides 2 speaker interfaces and 2 microphone interfaces. Only one pair I/O works at the same 
time.  
 

 

  Microphone 
The two microphone interfaces MIC_N and MIC_P are differential interface, which could also be used for 
single end input. It’s recommended to use differential mode to reduce the noises and it is directly connected with 
the receiver. MIC_P is single ended interface, which could be directly connected to the microphone since the 
offset voltage is internally provided. 
  Earpiece 
The earpiece interface EAR1_P and EAR1_N are both differential interfaces with 32Ω  resistance; EAR2_P is 
single-ended interface with 32Ω  resistance and no coupling of capacitor is required.   
 
  Design of audio interface on the receiver 
Select the microphone with the sensitivity lower than -52dB since EAR1’s output power is 35mW and the max. 
gain inside MIC1 reaches 52dB.     
 

Note: if other kind of audio input method is adopted, the input signal should be within 1V. If the signal 

then network attenuation should be added 
  Design of audio interface on the earpiece 
Select the microphone with the sensitivity lower than -52dB since EAR2’s output power is 10.8mW and the 
max. gain inside MIC2 reaches 52dB. The level of MIC2_P PIN is about 1.8V. The receiver’s design is just the 
same as the receiver’s.