Users Manual Part 1

SIM8260A_Hardware Design_V1.05
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AM13,AM17,AM21,AM24,AM27,AM31,AM35,AM39,AH13,AH17,AH21,AH24,AH27,
AH31,AH35,AH39,AE13,AE17,AE21,AE24,AE27,AE31,AE35,AE39,AA13,AA17,AA
21,AA24,AA27,AA31,AA35,AA39,U13,U17,U21,U24,U27,U31,U35,U39,P13,P17,P
21,P24,P27,P31,P35,P39,K13,K17,K21,K24,K27,K31,K35,K39,A1,B4,C7,A51,B48,
C45,BA1,AY4,AW7,BA51,AY48,AW45,AM49,AK49,AE51,AJ51,AN51,AU51

Both C1 and C5 are 220 µF tantalum capacitor (ESR=0.7Ω).

C3, C4, C7 and C8 are multi-layer ceramic chip (MLCC) capacitors from 33pF to 1uF with low ESR
in high frequency band, which can be used for EMC performance.

D1 is used for surge protection.

Pins AF45, AE47, AD49, AB49, AA51, AD49, W51, U51, T49 and R47 of GND are the main ground
for power return.
Table 10: Recommended D1 list
Name
Manufacturer
Part number
D1
LRC
LEDZ5.1BT1G
Prisemi
PZ5D4V2H
Power supply layout guidelines:

Both VBAT and return path should be as short and wide as possible to minimize the voltage drop.
 The width of VBAT_BB trace should be no less than 1.5mm, and the width of VBAT_RF trace should be
no less than 2mm. ESR<20mΩ
 These capacitors should be placed as closely as possible to the VBAT_BB and VBAT_RF pins.
 The VBAT trace should pass through Zener diode and capacitors, and then pass through the VBAT
pins. The small value capacitors should be placed close to the VBAT pins.
 The customer’s PCB design must have a solid ground plane throughout the board as the primary
reference plane for most signals.
3.1.2 Recommended Power Supply Circuit
It is recommended to use a switching mode power supply or a linear regulator power supply. Make sure it
can provide the current up to 3A at least.
The following figure shows the linear regulator reference circuit with 5V input and 3.8V output.
NOTE