Troubleshooting - Global Positioning System (Gps) Engine - Nokia NPD-4 Series Troubleshooting - Gps

CCS Technical Documentation

Troubleshooting - Global Positioning System (GPS) Engine

The NPD-4 handset supports 800 Amps and 800 CDMA / 1900 CDMA + GPS with IS 2000
capability. The NPD-4 engine supports CDMA and GPS functionality for Enhanced 911
(E911) services.
GPS circuitry utilizes RF signals from satellites stationed in geosynchronous orbit to
determine latitude and longitude of the handset. The GPS circuitry and the cellular
engine (CE) circuitry are completely separate in the handset. The GPS circuitry is located
almost exclusively on the secondary side of the PWB, underneath the display module.
See Figure 1 for the General Block Diagram.
LNA
TCXO
16.364Mhz
VLNA (2.8V)
Issue 1 02/2003
AGC
PLL
RF
RF Ctrl
RF
I/F
ASIC
Ctrl I/F
Oscillator
VRF (2.8V)
Vbatt
2nd regulator for
VLNA is optional
(Not Populated)
Gnd
Secondary UART
(Diagnostic)
Cellular Engine
Cellular
RF
Figure 1: GPS Block Diagram
Nokia Corporation
BB
ASIC
Baseband
4 GPS Data
RF-BB
A/D
I/F
(1.8V)
GPS Clk
SPI
Interface
RF
Control
I/F
(1.8V)
Vbatt
RTC CAL
TCXO CAL
Gnd
1.8V GPS BB/Cellular I/F
System Clock
19.2MHz (CDMA)
System Clock
UPP
Confidential
NPD-4
Troubleshooting — GPS
GPS Engine
Core
ARM
RAM
4
32768Hz
crystal
SLEEPX
SLEEP CLK
UEM
Vcore
REG
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