USGlobalsat ET-314 User Manual

ET-314

Version 1.2

GPS Engine Board ET-314

Version 1.2

06/22/2007

Globalsat Technology Corporation Headquarters (Far East Century Park)

16F., No. 186, Jian-Yi Road, Chung-Ho City, Taipei Hsien 235, Taiwan

Tel: [phone]/ Fax: [phone]

E-mail : [e-mail]

Website: www.globalsat.com.tw

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ET-314

Version 1.2

1. Product Information



Product Name: ET-314

Product Description:



ET-314 is a compact, high performance, and low power consumption GPS engine board. It uses SiRF

Star III chipset which can track up to 20 satellites at a time and perform fast TTFF in weak signal

environments. ET-314 is suitable for the following applications:

‧ Automotive navigation
‧ Personal positioning
‧ Fleet management
‧ Marine navigation

 Product Features:

 SiRF star III high performance GPS Chipset
 Very high sensitivity (Tracking Sensitivity: -159 dBm)
 Extremely fast TTFF (Time To First Fix) at low signal level
 Two serial ports
 4Mb flash
 Compact size (25.4mm * 25.4 mm * 3.3mm) suitable for space-sensitive application
 One size component, easy to mount on another PCB board
 Support NMEA 0183 and SiRF binary protocol

 Product Specifications

Chipset

Frequency L1, 1575.42 MHz

Code C/A Code

Protocol NMEA 0183 v2.2

GPS Receiver

SiRF StarⅢ

Default:GGA,GSA,GSV,RMC

Support:VTG,GLL,ZDA)

SiRF binary and NMEA Command

Available Baud Rate 4,800 to 57,600 bps adjustable

Channels 20

Flash 4Mbit

The Specifications are subject to be changed without notice. Copyright © 2007, GlobalSat Technology.

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ET-314

Sensitivity Tracking:-159dBm

Cold Start 42 seconds, average

Warm Start 38 seconds, average

Hot Start 1 second, average

Reacquisition 0.1 second, average

Accuracy Position: 10 meters, 2D RMS

5 meters, 2D RMS, WAAS enabled

Velocity: 0.1 m/s

Time: 1us synchronized to GPS time

Version 1.2

Maximum Altitude

Maximum Velocity

Maximum Acceleration

Update Rate 1 Hz

DGPS WAAS, EGNOS, MSAS

Datum WGS-84

I/O Pins 2 serial ports

Type 30-pin stamp holes

Dimensions 25.4 mm * 25.4 mm * 3.3 mm

Power Supply

Backup Voltage

Power Consumption

＜ 18,000 meter

＜ 515 meter/second

＜ 4G

Interface

Physical Characteristic

DC Characteristics

3.3Vdc ± 5%

2.0 ~ 3.6Vdc ± 10%

Acquisition: 42mA
Tracking: 25mA

Environmental Range

Humidity Range 5% to 95% non-condensing

Operation Temperature

Storage Temperature

-40℃ to 85℃

-40℃ to 125℃

The Specifications are subject to be changed without notice. Copyright © 2007, GlobalSat Technology.

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ET-314

2. Technical Information

 Block Diagram

Version 1.2

 Module Pin Assignment:

The Specifications are subject to be changed without notice. Copyright © 2007, GlobalSat Technology.

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ET-314

Pin Signal Name I/O Description

1 VCC I DC Supply V oltage input
2 GND G Ground
3 Boot select I Boot mode
4 RXA I Serial port A
5 TXA O Serial port A
6 TXB O Serial port B
7 RXB I Serial port B
8 GPIO14 I/O General –purpose I/O
9 RF_ON

10 GND G Digital Ground

Version 1.2

11

16
17 RF_IN I GPS Signal input
18 GND_A G Analog Ground
19 V_ANT_IN I Active Antenna Bias voltage
20 VCC_RF O Supply Antenna Bias voltage
21 V_BAT I Backup voltage supply
22 Reset I Reset (Active low)
23 GPIO10 I/O General purpose I/O
24 GPIO1 I/O General purpose I/O
25 GPIO5 I/O General purpose I/O
26 GPIO0 I/O General purpose I/O

27 GPIO13 I/O General purpose I/O
28 GPIO15 I/O General purpose I/O
29 PPS O One pulse per second

GND_A G Analog Ground

(support continuous power mode only)

30 GND G Digital Ground

Definition of Pin assignment

VCC

The Specifications are subject to be changed without notice. Copyright © 2007, GlobalSat Technology.

This is the main DC supply for a 3.3V +- 5% DC input power module board.

GND

GND provides the ground for digital pa

rt.

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ET-314

Boot select

Set this pin to high for programming flash.

RXA

Version 1.2

This is the main receiver channel and is used to receive software commands to the board from
SIRFdemo software or from user written software.
PS:

RXB

Pull up

if

not used.

This is the auxiliary receiving channel and is used to input differential corrections to the board to
enable DGPS navigation.
PS:

TXA

Pull up

if

not used.

This is the main transmitting channel and is used to output navigation and
measuremen

TXB

t

data to SiRFdemo or user written software.

For user’s application (not currently used).

RF_ON

This pin indicates state of RF voltage.

RF_IN

This pin receiver signal of GPS analog .due to the RF characteristics of the signal the design has
to certain criteria. The line on the PCB from the antenna(or antenna connector) has to be a
controlled microstrip line at 50Ω

V_ANT_IN

This pin is reserved an external DC power supply for active antenna.
If

using 3.3V active antenna, pin 19 has to be connected to pin 20.

If the bi as voltage of active isn’t 3.3V

,you can input bias voltage of you need to this pin.

VCC_RF

This pin provides DC voltage 3.3 for active antenna. Reset

The Specifications are subject to be changed without notice. Copyright © 2007, GlobalSat Technology.

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