Integration Guide

Table Of Contents
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Voltage Reference - VREG_MSME1.8 (PIN 77)
To be used as a voltage reference source ONLY. Do not connect current loads to this pin.
When driving external circuitry, this pin should be decoupled to ground with at least a 0.1 µF
capacitor at the output.This pin can be left open if not driving external circuitry. Noise
induced on this pin will affect the performance of the baseband.
USB (PINS 1, 3, 5, 7)
As part of integrated products carrier certification, most carriers require access to
the USB diagnostic port to control the module for testing. If the integrator has not
already brought out the USB interface, it is recommended that the USB interface
be routed to test points on the device, at a minimum. It will be acceptable to
temporary wire a USB connector for purposes of testing during carrier
certification.
5V Tolerant Transceiver
USB Parameter/Conditions Min Typ Max Units
Input Voltage 4.4 4.65 5.25 V
Output voltage High (Driven) 2.8 3.4 3.6 Vdc
Low 0.0 0.1 0.3 Vdc
Transceiver D+/- Leakage Current -2 2 μA
USB D+/- should be routed differentially for 90 ohms impedance. Take care not to
route the USB near sensitive circuitry.
General Purpose Input/Output Interface
GPIO number Pin number
GPIO 1 64
GPIO 2 62
GPIO 3 60
GPIO 4 58
GPIO 5 68
GPIO 6 70