Novatel OM-20000077 Computer Hardware User Manual


 
24 SUPERSTAR II User Manual Rev 3
Chapter 3 Installation
Interface between SUPERSTAR II and customer application:
Suggested Supplier: Omni Spectra
Supplier part number: 5831-5001-10
or
Suggested Supplier: Suhner
Supplier part number: 11MCX-50-2-10C
or
Suggested Supplier: Radiall
Supplier part number: R113082.
The center conductor provides power for an active antenna (PREAMP signal from J1-1).
3.4.3.1 Preamplifier Power Pass-Through (Antenna Supply)
The PREAMP signal is available on the I/O connector for the host to provide power to the antenna preamplifier
through the center conductor of the RF cable J2. The maximum operating voltage for an active antenna supply
(PREAMP) is 12 Volts.
CAUTION: You should use a current-limiting power source. The maximum current on J2 is 40 mA.
3.4.3.2 RF Input
The receiver will receive the GPS signal from the antenna amplifier on the J2 RF input connector. The RF input
port impedance is 50 Ohms nominal.
3.4.4 Memory Back-Up
The SUPERSTAR II has a supercap device allowing a warm start, where the receiver has an approximate
position, an approximate time and a valid almanac, without the need of an external power supply during a
power-off state. VBATT is an external back-up source for the time keeping circuit.
A warm start is available for 1 week typically (25°C) and 3 days over a more extreme temperature range (-30 to
+75°C). Therefore, VBATT can be used to extend the time retention period.
An external series diode will be required between J1 and the external power source to prevent the supercap
from discharging into your circuitry.
3.5 Protocol Selection and Non Volatile Memory
Discrete IOs are available with a SUPERSTAR II card. A summary is shown in Table 3 on Page 25.