u-blox LEA-5T User Manual

LEA-5, NEO-5, TIM-5H - Hardware Integration Manual
GPS.G5-MS5-09027-A2 Released Design-in
Page 40 of 68
To test GPS signal reacquisition, it is recommended to physically block the signal to the antenna, rather
than disconnecting and reconnecting the receiver.
2.6.3 Active antenna (LEA-5Q/5M, NEO-5)
LEA-5Q/5M and NEO-5 modules do not provide the antenna bias voltage for active antennas on the RF_IN pin. It
is therefore necessary to provide this voltage outside the module via an inductor as indicated in Figure 31. u-Blox
recommends using an inductor from Murata (LQG15HS27NJ02). Alternative parts can be used if the inductor‖s
resonant frequency matches the GPS frequency of 1575.4MHz.
Low Noise Amplifier
Active Antenna
RF_IN
VCC_RF
GND
GND
10
Figure 31: Recommended wiring for active antennas (for exact pin orientation see data sheet)
For optimal performance, it is important to place the inductor as close to the microstrip as possible. Figure 30
illustrates the recommended layout and how it should not be done.
GND
Microstrip
GND
RF_IN
Antenna Supply Voltage
(e.g. VCC_RF)
Inductor L
GND
GND
Antenna Supply Voltage
(e.g. VCC_RF)
Inductor L
Microstrip
RF_IN
Good Bad
Figure 32: Recommended layout for connecting the antenna bias voltage for LEA-/5M and NEO-5

u-blox LEA-5T Specifications

General

Brand	u-blox
Model	LEA-5T
Category	GPS
Language	English