Jackson Labs LC_XO Manual

Low cost ultra small 1x1 inch gpsdo module spec

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LC_XO Low Cost Ultra Small 1x1 inch GPSDO Module Spec

TYP. ELECTRICAL SPECIFICATIONS:

Module Specification:

1 PPS Accuracy

Holdover Stability

1 PPS Output

Serial Control

GPS Frequency

GPS Antenna

GPS Receiver

Sensitivity

GPS TTFF

ADEV

TTL Alarm Output

Warm Up Time / Stabilization Time

Supply Voltage (Vdd)

Power Consumption

Operating Temperature

Storage Temperature

Additional Features

Oscillator Specification (OCXO):

Frequency Output

10MHz Retrace

Frequency Stability Over Temperature (Unlock Condition)

Output Amplitude

OCXO Warm Up Time

Phase Noise (with 33uF or larger cap on 5V_Output pin 6)

Connections:

1PPS Output, 10MHz Output, power, serial communication, system

status, NMEA, 1PPS in, ISP mode enable, antenna input

Jackson Labs Technologies, Inc., 475 Alberto Way, Suite 120, Los Gatos, CA 95032

Phone: (408) 354-7888, Fax: (408) 354-7880,

<±20us over 3 Hour Period @+25°C (No Motion, OCXO)

50 Channels, Mobile, SBAS WAAS, EGNOS, MSAS capable

Cold Start - <45 sec, Warm Start – 1 sec, Hot Start - 1 sec

10Ks <5E-012 (OCXO, GPS Locked, 25°C, no motion)

3.3V Single-Supply only (5V internally generated and filtered)

Firmware field-upgradable, external 1PPS input, status LEDs, compatible

to GPSCon, SNTP, GPSD, and Z38xx software applications, full NMEA

100 mil spacing on pins, can be soldered, or plugged into a socket, gold-

sales@jackson-labs.com

 0.97 X 0.97 X 0.5 inch Module with

pins

 < 1 Min. Crystal Warm Up

 50 Channel WAAS GPS Receiver

 Very Low Power, TCXO or OCXO



PRELIMINARY SPECIFICATION

±50ns to UTC RMS (1-Sigma) GPS Locked

3.3VDC CMOS

SCPI-99 TTL Level, GPS NMEA Output

L1, C/A 1574MHz

Active or Passive

Acquisition –142 dBm, Tracking -158 dBm

GPS LOCK indicator

<5 min at +25°C to 1E-08 Accuracy

0.7W with OCXO, 0.5W with TCXO

0°C to +60°C, -20C to +75C optional

-45°C to +85°C

10MHz CMOS 5Vpp (3.3Vpp optional)

±2E-08 After 1 Hour @ +25°C

±2.5E-08 (OCXO) ±7.5E-08 (TCXO)

5Vpp CMOS

< 1 min @ +25°C

TCXO

1Hz

-65dBc/Hz

10Hz

-102dBc/Hz

100Hz

-132dBc/Hz

1kHz

-148dBc/Hz

10kHz

-152dBc/Hz

100KHz

<-155dBc/Hz

<-150dBc/Hz

Connector Type:

plated pins

www.jackson-labs.com

OCXO

-75dBc/Hz

-110dBc/Hz

-132dBc/Hz

-142dBc/Hz

-145dBc/Hz

Revision 08/29/12 B

Table of Contents

Summary of Contents for Jackson Labs LC_XO

Page 1 100 mil spacing on pins, can be soldered, or plugged into a socket, gold- status, NMEA, 1PPS in, ISP mode enable, antenna input plated pins Jackson Labs Technologies, Inc., 475 Alberto Way, Suite 120, Los Gatos, CA 95032 Phone: (408) 354-7888, Fax: (408) 354-7880, www.jackson-labs.com sales@jackson-labs.com...
Page 2 LC_XO PINOUT DESCRIPTION: Revision 08/29/12 B...
Page 3 User LC_XO GPSDO Manual Document: 80200517 Version: Date: 23 September, 2012...
Page 5: Table Of Contents
2.1 Powering Up the Unit ......3 2.1.1 LC_XO Photos ......3 2.1.2 LC_XO Mechanical Diagram .
Page 9: Introduction
PCB. All that is required to operate the LC_XO board is a 3.3V power supply, and a GPS antenna feed. The unit provides an industry-standard NMEA GPS interface providing Position/Velocity/Timing (PVT) information, as well as full control/command serial interface using SCPI (GPIB-like) serial commands.
Page 10: Power Connections
This instrument is intended for indoor use. It is designed to operate at a maximum relative non-condensing humidity of 95% and at altitudes of up to 50,000 meters. Refer to the specifications tables for the ac mains voltage requirements and ambient operating temperature range. © 2012 Jackson Labs Technologies, Inc.
Page 11: Quick-Start Instructions
The user should provide an L1 antenna signal routed on a microstrip or stripline to pin 10 on the unit. The antenna can be active or passive, with an amplification range of up to 50dB to compensate for cable loss. The LC_XO provides 5V with up to 40mA to the antenna and the output is short-circuit protected.
Page 12 LC_XO GPSDO User Manual Figure 2.1 LC_XO Module Top side Figure 2.2 LC_XO Module Bottom side © 2012 Jackson Labs Technologies, Inc.
Page 13: Lc_Xo Mechanical Diagram
LC_XO GPSDO User Manual 2.1.2 LC_XO Mechanical Diagram Figure 2.3 LC_XO Pin Locations and Outline Drawing © 2012 Jackson Labs Technologies, Inc.
Page 14: Lc_Xo Pinout And Pin Description
LC_XO GPSDO User Manual 2.1.3 LC_XO Pinout and Pin Description Figure 2.4 LC_XO Pinout and Pin Description © 2012 Jackson Labs Technologies, Inc.
Page 15 LC_XO GPSDO User Manual Table 2.1 shows the LC_XO board revision 1.0 hardware pin description Table 2.1 LC_XO board hardware connectors Name Function Specification 10MHz Out 10MHz output 5V CMOS, <1ns rise time LOCK_OK LOCK 3.3V: Unit is locked and no...
Page 16: Using A Socket
2.2 Using a Socket The LC_XO board may either be soldered onto a PCB or it can be inserted into a socket on the users’ PCB for optional retrofitting of customer products. The pins used on the LC_XO board are manufactured by Samtec and have part number BBL-115-G-E.
Page 17: Help" And Command Overview
Phase compensation: this is the Integral part of the PID loop. This corrects phase offsets between the LC_XO board 1PPS signal and the UTC 1PPS signal as generated by the GPS receiver. Set higher values for tighter phase-following at the expense of frequency stability. Typical values range from 4 - 30, 25 being the default.
Page 19: Control And Command Utilities
Control and Command Utilities 3.1 Description The LC_XO board can be connected to a freeware program available on the Jackson Labs Technologies, Inc. website support page to control and monitor the unit called Z38xx. This program runs under Windows. Z38xx can be used to monitor and graphically plot the frequency and phase stability of the unit, the number of Satellites being tracked, and various other GPS and TCXO performance parameters.
Page 20: Serial Echo
SYST:COMM:SER:ECHO OFF. Wait until the yellow indicator is lit and then press “Send”. This will send a command to the LC_XO and turn off serial echo. Note: If you want to run GSPcon utility subsequently, be sure and turn back on Serial Echo as that program requires it.
Page 21: Windows Compatibility
Windows in XP Compatibility Mode. This will ensure proper operation of the program. Of course, you can try running under Windows Vista or 7 as it does work on some systems. © 2012 Jackson Labs Technologies, Inc.
Page 22: Running The Program
To pan within the graph display, use the right mouse button to drag the graph around the window. Figure 3.3 Z38XX main window 3.2.3 View menu The View menu allows you to view different aspects of the LC_XO performance such as: • Satellite Azimuth/Elevation Chart •...
Page 23: Satellite Azimuth/Elevation Chart
3.2.3.2 Satellite C/N level Chart Select Satellite C/N level Chart from the View menu and observe the chart shown in Figure 3.5. This graph show the Carrier to Noise ratio of each satellite being tracked. © 2012 Jackson Labs Technologies, Inc.
Page 24: Holdover Uncertainty & Sats
Select Time Stability Measures from the View menu to bring up the chart shown in Figure 3.6. This chart is primarily used to display the Allan Deviation for the LC_XO. To learn more about the different display parameters for this window, please consult the Z8XX User Manual. © 2012 Jackson Labs Technologies, Inc.
Page 26: Gpscon Utility
Before you can use GPSCon you must set the communication parameters for your system. Open the dialog box by pressing the “Options” button. Then select the “Coms” tab. You will see the window shown in Figure 3.8. © 2012 Jackson Labs Technologies, Inc.
Page 27: Auxiliary Parameters
Once you have configured the communication parameters, press the “OK” button to close the window. For proper communication between the LC_XO GPSDO and GPScon, SYST:COMM:SER:ECHO must be set to ON. Although this is the factory default, it could have been set to OFF for use with the Z38XX utility.
Page 29: Other Options
3.10. Care must be taken when sending these commands so be sure that the command that you select is supported by the LC_XO GPSDO board. Once you’ve selected the command, you can press “Send” to send it to the LC_XO board.
Page 30: Use Of The Mouse In Graph Mode
And, finally to return to the zoomed out ("fit to window") view, left double-click on the curve." © 2012 Jackson Labs Technologies, Inc.
Page 31 Shift + Right click. Double left click to release everything. The time span indication at the lower right of the graph will turn red to signify that mouse override is in effect. Figure 3.11 Graph display © 2012 Jackson Labs Technologies, Inc.
Page 32: Exporting The Graphics
The export may be done automatically on a timed basis. Simply enter a non-zero value in seconds to choose an export time interval. To manually export in accordance with the settings, press the 'Export' button. © 2012 Jackson Labs Technologies, Inc.
Page 33: Interpreting The Data
3.4 Interpreting the Data Figure 3.11 shows the data acquired by the LC_XO board unit over a period of more than 200 hours The red trace is EFC (crystal frequency control voltage). The crystal is aging (becoming faster in frequency over time). This requires the control voltage to be lowered to maintain 10.0MHz exactly.
Page 34: Performance
Figure 3.13 Typical LC_XO Allan Deviation (TCXO version) Figure 3.14 is a plot of typical LC_XO board phase noise performance while locked to GPS. The noise floor can be seen to be below -155dBc. © 2012 Jackson Labs Technologies, Inc.
Page 35 LC_XO GPSDO User Manual Figure 3.14 Typical LC_XO Phase Noise (TCXO version) © 2012 Jackson Labs Technologies, Inc.
Page 37: Scpi-Control Quick Start Instructions
Symmetricom 58503A commands.To get a listing of the available commands, send the HELP? query. This will return a list of all the available commands for the LC_XO GPSDO. Additional information regarding the SCPI protocol syntax can be found on the following web site: http://www.scpiconsortium.org...
Page 38: Help
This query returns a list of the commands available for the FireFly GPSDO. 4.3 GPS Subsystem Note: Please note that LC_XO displays antenna height in MSL Meters rather than in GPS Meters on all commands that return antenna height [the legacy Fury GPSDO uses GPS height].
Page 39: Gps:gpgga
Please note that the position, direction, and speed data is delayed by one second from when the GPS receiver internally reported these to the LC_XO Microprocessor, so the position is valid for the 1PPS pulse previous to the last 1PPS pulse at the time the data is sent (one second delay). The time and date are properly output with correct UTC synchronization to the 1PPS pulse immediately prior to the data being sent.
Page 40: Gps:xyzspeed
The PTIME subsystem regroups all the commands related to the management of the time.The list of the commands supported is the following : PTIMe:TZONe? PTIMe:DATE? PTIMe:TIME? PTIMe:TIME:STRing? PTIMe:TINTerval? PTIME? 4.4.1 PTIMe:TZONe? Returns the local time zone offset. © 2012 Jackson Labs Technologies, Inc.
Page 41: Ptime:date
PTIME:DATE? PTIME:TIME? PTIME:TZONE? PTIME:TINTerval? 4.5 SYNChronization Subsystem This subsystem regroups the commands related to the synchronization of the LC_XO with the GPS receiver. The list of the commands supported for this subsystem is the following: SYNChronization:SOURce:MODE [GPS|EXTernal|AUTO] SYNChronization:SOURce:STATE? SYNChronization:HOLDover:DURation? SYNChronization:HOLDover:INITiate...
Page 42: Synchronization:source:mode [Gps|External|Auto]
The board may be configured lock to an external 1PPS source, or the internal GPS receiver. Pin 5 on the LC_XO may be used to feed an external CMOS rising-edge 1PPS signal with 0V < x <5V signal level, and 1us minimum pulse width into the unit.
Page 43: Synchronization:feestimate
1) UTC phase > 250ns: 0x4 2) GPS in holdover: 0x10 ‘Oring’ these values together results in: 0x10 | 0x4 = 0x14 The unit would thus indicate: HEALTH STATUS: 0x14 © 2012 Jackson Labs Technologies, Inc.
Page 44: 10Synchronization
4.7 MEASURE Subsystem The MEASURE commands are not supported on the LC_XO board. 4.7.1 MEASure:VOLTage? This command is not supported on LC_XO, and will return undetermined values. 4.7.2 MEASure:CURRent? This command is not supported on LC_XO, and will return undetermined values.
Page 45: Measure
This command is not supported on LC_XO, and will return undetermined values. 4.8 SYSTEM Subsystem This subsystem regroups the commands related to the general configuration of the LC_XO. The list of the commands supported for this subsystem follows: SYSTem:COMMunicate:SERial:ECHO <ON | OFF>...
Page 46: Servo Subsystem
SERVo:TRACe <int > [0,255] SERVo? 4.9.1 SERVo:COARSeDac This command sets the coarse Dac that controls the EFC. The LC_XO control loop automatically adjusts this setting. The user should not have to change this value. This command has the following format: SERVo:COARSeDac <int>...
Page 47: Servo:slope
This parameter is a coefficient that represents the drift of the EFC needed to compensate the natural drift in frequency of the OCXO due to aging. This coefficient is automatically computed and adjusted over time by the Jackson Labs Technologies, Inc. firmware. This command has the following format: SERVo:AGINGcompensation <float> [-10.0, 10.0] 4.9.8 SERVo:PHASECOrrection...
Page 48: 11Servo
Holdover, but still phase locked (stays in this state for about 100s after GPS lock is lost) Locked, and GPS active 4.9.11 SERVo? This command returns the result of the following queries: SERVo:COARSeDac? SERVo:DACGain? SERVo: EFCScale? SERVo:EFCDamping? SERVo:SLOPe? SERVo:TEMPCOmpensation? SERVo:AGINGcompensation? SERVo:PHASECOrrection? SERVo:1PPSoffset? SERVo:TRACe? © 2012 Jackson Labs Technologies, Inc.
Page 49: Certification And Warranty
Except for products returned to Customer from another country, Jackson Labs Technologies, Inc. shall pay for return of products to Customer. If Jackson Labs Technologies, Inc. is unable, within a reasonable time, to repair or replace any product to condition as warranted, the Customer shall be entitled to a refund of the purchase price upon return of the product to Jackson Labs Technologies, Inc.
Page 50: Exclusive Remedies
LC_XO GPSDO User Manual PURPOSE. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this document. Jackson Labs Technologies, Inc. products are not intended for use in medical, life saving, or life sustaining applications.

Jackson Labs LC_XO Manual

1 Introduction

2 Quick-Start Instructions

3 Control and Command Utilities

4 SCPI-Control Quick Start Instructions

5 Certification and Warranty

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Summary of Contents for Jackson Labs LC_XO

Table of Contents