User Manual
    Smart Machine Smart Decision 
 SIM7600A-H_User Manual_V1.00    2017-11-24 
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In addition, in order to guard over voltage protection, it is suggested to use a zener diode with 5.1V 
reverse zener voltage and more than 500mW power dissipation. 
Table 7: Recommended zener diode list 
No.  Manufacturer  Part Number  power dissipation  Package 
1  On semi  MMSZ5231BT1G  500mW  SOD123 
2  Prisemi  PZ3D4V2H  500mW  SOD323 
3  Vishay  MMSZ4689-V  500mW  SOD123 
4  Crownpo  CDZ55C5V1SM  500mW  0805 
3.1.2  Recommended Power Supply Circuit 
It is recommended that a switching modepower supply or linear regulator power supply is used. It 
is important to make sure that all the components used in the power supply circuit can resist a peak 
current up to 2A. 
The following figure shows the linear regulatorreference circuit with 5V input and 3.8V output. 
Figure 6: Linear regulator reference circuit 
If there is a big voltage difference between input and output for VBAT power supply, orthe 
efficiency is extremely important,then a switching mode power supply will be preferable. The 
following figure shows theswitching mode power supply reference circuit. 
Figure 7: Switching modepower supply reference circuit 
Note: The Switching Mode power supply solution for VBAT must be chosen carefully against 
Electro Magnetic Interference and ripple current from depraving RF performance.   










