TVS(ESD:VRWM 5V
Diode (Schottky rectifier) : VR: 10-20V SOD123/Sot -23
Small-signal MOSFET for switches: VDSS: 20-60, SOT-23/323/523
Small signal transistors for switches: MMBT3904/3906, S8050/8550
LDO voltage regulator chip for power supply
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It is required to reduce space, use smaller package to achieve high power performance, not easily affected by noise and surge
Noise and interference around the wireless interface need to be eliminated
Need to work in a long time, maintain low heat operation to ensure the stability of transmission
Long enough service life is required