Usb Routing Recommendations; Power And Ground Recommendations; Figure 4. Antenna Microstrip Routing Example - Sierra Wireless AirPrime AR7582 Hardware Integration Manual

Hardware Integration Guide
GND
GND
AR759x
GND
GND
Figure 4. Antenna Microstrip Routing Example
3.2.

USB Routing Recommendations

HighSpeed USB signals (USB_D_P / USB_D_M) are a differential pair and must be routed with the
following considerations/constraints:

90 Ohm differential +/- 10% trace impedance,

Differential trace length pair matching < 2mm (15 ps),

Solid reference planes,

Trace lengths < 120 mm,

And 2x the trace width separation to all adjacent signals.
SuperSpeed USB adds two differential pairs (SSRX+ / SSRX- and SSTX+ / SSTX-). These pairs
should be routed with the following considerations/constraints:

90 Ohm differential +/- 15% trace impedance,

Differential trace length pair matching < 0.7mm (5 ps),

Trace lengths < 112 mm,

And GND isolation from other adjacent traces with minimum of 2x the SSRX/SSTX trace
wdith.
3.3.

Power and Ground Recommendations

Power and ground routing is critical to achieving optimal performance of the AirPrime AR758x Series
when integrated into an application.
Recommendations:

Do not use a separate GND for the Antennas.

Connections to GND from the AirPrime AR758x Series should be flooded plane using thermal
reliefs to ensure reliable solder joints.

VBATT is recommended to be routed as a wide trace(s) directly from the power supply to the
LGA pad.
41110461XXXX
GND
50 Ohm Controlled Impedance Trace
ANT
GND 2x Ground holdback – twice
the trace width
Rev 0.12
Routing Constraints and Recommendations
RF Connector
GND GND
GND GND
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