Mini-JLT GNSS Disciplined Oscillator (GPSDO) Board

GNSS-disciplined oscillator board with a 72-channel concurrent GNSS receiver, form-fit-function compatible with the Trimble Mini-T.

1 PPS Stability: <±10 ns to UTC RMS (1-Sigma)
Serial Control: GPS NMEA and Status Output, SCPI-99 control, USB and TTL Port
GPS Frequency, Antenna Power: C/A 1574 MHz, 3.3 V antenna-power built-in, 5 V external supply option
GPS Receiver: 72 Channels, GPS, Glonass, Galileo, BeiDou, QZSS, SBAS capable

Datasheet

Overview

The VIAVI Mini-JLT board is a GNSS-disciplined oscillator (GPSDO) module designed as a replacement for the end-of-life Trimble Navigation Limited Mini-T GPSDO units. It is form-fit-function compatible with the Trimble units.

Later product revisions add concurrent-GNSS capability. The board can track up to three GNSS systems at the same time, such as GPS, Galileo, Glonass, BeiDou and QZSS, with full SBAS support.

The Mini-JLT also adds features the Mini-T does not have: a 1 PPS external input, a 3-axis on-board accelerometer, USB communication, an internal antenna power supply, a wide-range main power supply and an extended temperature range. It stands 0.5 inches above the PCB instead of 0.8 inches. VIAVI also states that its thermal stability, Allan deviation and phase noise performance are improved.

The unit is controlled with NMEA and SCPI commands. It does not support the proprietary TSIP command set.

Key Features

Form-fit-function compatible with Trimble Mini-T
72-channel concurrent GNSS receiver
Tracks up to three concurrent GNSS systems (GPS, Galileo, Glonass, BeiDou, QZSS) with SBAS support
Extended temperature range -40°C to +80°C
USB and TTL serial communication
Additional 10 MHz +13 dBm output port
TTL LOCK/EVENT# and GPS-FIX indicator
1 PPS external input
3-axis on-board accelerometer
Internal antenna power supply
Wide-range main power supply
Lower overall height: 0.5 inches vs. 0.8 inches above the PCB
NMEA and SCPI command support

Specifications

Module Specifications

1 PPS Stability	<±10 ns to UTC RMS (1-Sigma) GPS Locked (DOCXO)
Serial Control	GPS NMEA and Status Output, SCPI-99 control, USB and TTL Port
GPS Frequency, Antenna Power	C/A 1574 MHz, 3.3 V antenna-power built-in, 5 V external supply option
GPS Receiver	72 Channels, GPS, Glonass, Galileo, BeiDou, QZSS, SBAS capable
Sensitivity, Acquisition	-148 dBm
Sensitivity, Tracking	-167 dBm GPS and Glonass
GPS TTFF, Cold Start	<30 sec
GPS TTFF, Warm Start	2 sec
GPS TTFF, Hot Start	2 sec
Holdover	<5 µs in 5 hours (SOCXO), <4 µs in 24 hours (DOCXO) at 25.0°C, no airflow, no motion/vibration, 5 days GPS locked
Warmup and Stabilization Time	<12 min at +25°C to <1E-09 Accuracy to GPS
1 PPS External Reference Input	Supports an optional external 1 PPS input on pin 1 of power connector
10 MHz Outputs	1x 10 MHz at +5 dBm, 1x optional 10 MHz at +13 dBm, ±3 dB
3-axis Accelerometer	Up to 20 readings/s, can be used for electronic g-compensation option

Allan Deviation

ADEV 1 s SOCXO	<7E-012
ADEV 1K s SOCXO	<7E-011
ADEV 10K s SOCXO	<8E-012 25°C, no motion/airflow
ADEV 1 s DOCXO	<5E-012 DOCXO option
ADEV 1K s DOCXO	<3E-011 DOCXO option
ADEV 10K s DOCXO	<3E-012 DOCXO option; 25°C, no motion/airflow

Oscillator Specification

Frequency Output	10 MHz at +5 dBm and +13 dBm
10 MHz Retrace	<±1E-09 After 1 hour @ +25°C (no GPS)
Frequency Stability over Temperature over 24 hours	±6E-09 (SOCXO), ±0.5E-09 (DOCXO), <1E-012 over 24 hours (with GPS)
Output Harmonics, Spurs	<-50 dBc/Hz, <-115 dBc/Hz
OCXO Aging	<±0.1 ppm per year without GPS fully compensated by GPS

Phase Noise @ 10 MHz

1 Hz SOCXO	-90 dBc/Hz
1 Hz DOCXO	-94 dBc/Hz
10 Hz SOCXO	-128 dBc/Hz
10 Hz DOCXO	-132 dBc/Hz
100 Hz SOCXO	-148 dBc/Hz
100 Hz DOCXO	-142 dBc/Hz
1 kHz SOCXO	-153 dBc/Hz
1 kHz DOCXO	-150 dBc/Hz
10 kHz SOCXO	-155 dBc/Hz
10 kHz DOCXO	-152 dBc/Hz
100 kHz SOCXO	<-155 dBc/Hz
100 kHz DOCXO	-152 dBc/Hz

Power and Environmental

Supply Voltage (Vdd)	5 V ±1.0 V
Power Consumption	<2.4 W (SOCXO), <3.2 W (DOCXO) @25°C, <8 W during warmup
Operating Temperature	-45°C to +80°C (SOCXO), 0°C to +75°C (DOCXO) Web page highlights state an extended temp range of -40°C to +80°C; datasheet value shown

Connections

2x 10 MHz Sine Wave Out, GPS Antenna	SMA second output not stuffed
+5 V Power, ext. 1 PPS input, TTL serial port, Ant. power (3.3 V to 5.5 V)	Molex PN 70543-0005
USB Communication	Mini USB, 2.0

Specifications are taken from the manufacturer's documentation. See the datasheet for complete and current values.

Applications

Defense
5G Communications
SATCOM
Transportation
Data Center
Energy
Financial
Critical Infrastructure

Options & Accessories

Option	Description
100306-G2	MINI JLT GNSS SOCXO - RoHS
100311-G2	MINI JLT GNSS SOCXO w/J5 Connector - RoHS
22174873	MINI JLT GNSS SOCXO R/A SMA - RoHS
22174874	MINI JLT GNSS SOCXO RS232 - RoHS
22174875	MINI JLT GNSS DOCXO RS232 - RoHS
22174865	MINI JLT DOCXO R/A 10MHz - RoHS
22174866	MINI JLT GNSS DOCXO - RoHS
22174867	MINI JLT GNSS DOCXO Low G - RoHS
22174868	MINI JLT DOCXO 6P Header MCX - RoHS