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SiRFstarIII™ GSD3tw

SiRFstarIII™ GSD3tw

Description

SiRFstarIII GSD3tw provides industry-leading GPS performance in a cost-saving, host-based implementation. Host-based GPS involves a GPS tracker engine combined with SiRFNavIII software running on the host system. By sharing the host system’s memory and CPU resources, total BOM cost and parts count is reduced. GSD3tw is ideally suited for applications that require tighter integration of the GPS function into a powerful CPU and RTOS at minimal cost and space.

Key features

High performance solution
Low power (typical)
Tiny solution size
Simple to use

Benefits

For cellular handset applications where space is at a premium, the GSD3tw offers two excellent package options, one for low cost production and one for small footprint mainstream design
The GSD3tw supports SiRFLoc Client, the patented Multimode A-GPS software powering mobile phones optimised for location-enabled services. SiRFLoc improves GPS location capability in wireless system environments by utilising various modes of wireless infrastructure assistance to improve weak signal reception
For personal navigation devices with high-end host processors, the GSD3tw with SiRFNav software provides SiRF Autonomous mode GPS navigation, setting a new performance benchmark for high-sensitivity navigation
Standard autonomous software also supports SiRFInstantFix technology, which eliminates the initial task of obtaining broadcast GPS data from the satellites themselves, resulting in a faster TTFFs, even in weak signal environments

GPS Architecture Highlights

Premium SiRFstarIII architecture with 200,000+ effective correlators for fast TTFF and high sensitivity acquisition
SiRFNav host software with: real-time navigation for location based services
Advanced Power Management and Adaptive TricklePower™ plus low energy-per-fix in point position applications
Multimode A-GPS support: Autonomous, MS Based, MS Assisted
Location protocol libraries supporting RRC, RRLP, 3GPP2, SUPL, E-911

Product details

High Performance Solution

Fast Time to First Fix (TTFF)
Up to 20 channel operation
3GPP and E911 compliant

Low Power (Typical)

24mW TricklePowerTM
45mW full power tracking when external LDOs used
67mW full power tracking when internal LDOs used
Typical hibernate current 10 μA

Tiny Solution Size

WLCSP solution 3.2 x 3.15 x 0.61mm, 0.4mm ball pitch
Total solution <30mm2 with shared resources
BGA option 4.5 x 4.0 x 0.68mm, 0.5mm ball pitch

Simple To Use

Host library portable to many popular processors
Host loading 4 MIPS or less with host FPU and
5 MIPS without host FPU. This is the average load on the host processor

Horizontal Position Accuracy

Autonomous <2.5 m

Velocity Accuracy

Speed <0.01 m/s
Heading <0.01°

Time To First Fix

Hot start - Autonomous <1 s
Warm start - Autonomous <36 s
Cold start - Autonomous <36 s
MS Based - GSM coarse time <0.6 s
MS Assisted - GSM coarse time <5.3 s

Sensitivity

Autonomous acquisition -147 dBm
GSM / UMTS coarse time aided -155 dBm
CDMA precise time aided -155 dBm
Tracking -159 dBm

Receiver

Tracking L1, CA Code
Channels up to 20
Max update rate 1 Hz
Max altitude/velocity <60,000 ft/<1,000 knots
Protocol support SSIII sat. signal processing

System Integration

I/O Interface UART and SPI
External reference clock 16.369, 16.8, 26, 38.4 MHz
RTC input 32.768 kHz

Power

Continuous tracking (1 Hz) 50 mW
TricklePower (1 Hz) 20 mW
Energy per fix 40 mW-s
Standby current 13µA

Host CPU Requirements

Typical processing load 5-7 MIPS

Size

Package dimensions 3.12 x 3.17 x 0.4 mm
Typical design footprint 30mm2

Subject to approval, a datasheet can be made available for this product via CSR Support.