User's Manual
Table Of Contents
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L850-GL Hardware User Manual Page
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Figure 3-10 Requirement of PCIe Line
The difference in length of two data lines in difference pair should be within 5mil, and the length
match is required for all parts. When the length match is conducted for the differential lines, the
designed position of correct match should be close to that of incorrect match, as shown in Figure
3-11. However, there is no specific requirements for the length match of transmit pair and receiving
pair, that is, the length match is only required in the internal differential lines rather than between
different difference pairs. The length match should be close to the signal pin and pass the
small-angle bending design.
Figure 3-11 Length Match Design of PCIe Difference Pair
3.6 USIMInterface
The L850 module has a built-in USIM card interface, which supports 1.8V and 3V SIM cards.
3.6.1 USIM Pins
The USIM pins descriptionas shown in the following table:
Pin
Pin Name
I/O
Reset Value
Description
Type
36
UIM_PWR
PO
USIM power supply
1.8V/3V