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3.4.3 EXTERNAL POWER
See Figure 3.2, Page 20 for external power input connections:
•
Digital ground = pins 1A/B (internally connected)
•
Vcc, main power (+5 V DC) = pins 2A/B (internally connected)
•
Optional external LNA power = pin 4B (30 V DC) and 4A (GND)
See Table B.1, Page 49, for specifications concerning external power inputs.
The MiLLennium-GLONASS GPSCard requires only one regulated power input of Vcc = +5 V D C .
It is possible to supply power to the LNA on an active antenna either from the MiLLennium-GLONASS GPSCard
or from an external source. The MiLLennium-GLONASS GPSCard is factory-configured for operation with the
single-frequency 504 or 514 GPS/GLONASS antenna models, in which case no special wiring or configuration is
required: the P301 jumper (see Figure 3.1 (Page 17) and Figure 3.3 following) is normally set for internal operation
(connects pins 1 and 2). The internal antenna power supply can produce 4.25 - 5.25 V DC at up to 90 mA. If the
antenna draws more than 90 mA of current, power to the antenna will be disabled and the antenna self-test status
flag set to zero; see Appendix H, RVSA/B log (Page 109) and Table H.2 (Page 96) for receiver self-test status codes.
If a different antenna is used whose LNA requires voltage and/or current capacity beyond what the MiLLennium-
GLONASS GPSCard can produce, then the external LNA power option must be utilized - this requires that P301
must be jumpered between pins 2 and 3. The input cannot exceed +30 V D.C. at 100 mA. When the LNA jumper
plug is in the external position, the antenna sensing circuit will cause the self-test status code to always report
antenna status as 1 (good). See Appendix H, RVSA/B log (Page 109) and Table H.2 (Page 96) for receiver self-test
status codes.
If no LNA power is required, remove the jumper at P301 completely.
In contrast to the physical jumper settings, it is the ANTENNAPOWER command which actually enables or
disables the supply of electrical power from the internal power source of the card to Pin 1 of jumper P301. By
default, ANTENNAPOWER = ON. Table 3.1, Page 22 illustrates the usage of this command in relation to the
jumper position.
The setting of this command will also affect the way the self-test diagnostics report the antenna's status; please see
the description of the ANTENNAPOWER command, Page 84.
GPS/GLONASS Receiver User Manual Rev 1
Figure 3.3 LNA Power Jumper P301 - 3 Cases
Reference
Description
1
Pin 1
2
Pin 2
3
Pin 3
4
Case 1: No power to LNA
5
Case 2: Internal power source (default)
6
Case 3: External power source
3 Installation
21
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