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SC806Hardware User ManualPage33 of 70
battery through the module’s internal PMU. The power input voltage range is 4.35~6.0V, and the recommended
value is 5V. The module supports single-cell lithium battery charge management. Different capacity models require
different charge parameters. The module’s built-in linear charge circuit supports up to 1.44A charge current.
The following is the USB interface circuit design:
Figure 10USB Interface Circuit Diagram
Note:
1) SC806 cannot output 5V DC internally, and 5V DC is required when USB is used as HOST.
2) ESD protection device for USB_DP/DM requires junction capacitance less than 1pF
3) USB_DP and USB_DM are high-speed differential signal traces. The highest transmission rate is 480Mbps.
Please pay attention to the following requirements in PCB layout:
USB_DP and USB_DM signal traces are required to be equal length and parallel, avoiding right-angle route,
and doing differential 90Ω impedance control
USB2.0 differential signal trace is laid on the nearest signal layer from the ground, and wrap ground
Table11module internal USB trace length
Pin No.
Pin name
Length (mm)
Length error (DP-DM)
13
USB_DM
28.70
-0.51
14
USB_DP
28.19
VBUS_5V
USB_DM
USB_DP
USB_ID
GND
G
N
D
G
N
D
G
N
D
G
N
D
USB_DM
USB_DP
USB_ID
VBUS_5V
1
2
3
4
5
Module
D2
C1
100nF
ESD