ZOE-M8B - System Integration Manual
UBX-17045131 - R04
Contents
Page 26 of 42
Production Information
2.13.2
Paste mask
The paste mask
shall be same as the copper pads with a paste thickness of 80 µm.
☞
These are recommendations only and not specifications. The exact geometry, distances, stencil
thicknesses and solder paste volumes must be adapted to the specific production processes (e.g.
soldering etc.) of the customer.
2.13.3
Placement
A very important factor in achieving maximum GNSS performance is the placement of the receiver on
the PCB. The connection to the antenna must be as short as possible to avoid jamming into the very
sensitive RF section.
Make sure that RF critical circuits are clearly separated from any other digital circuits on the system
board. To achieve this, position the receiver digital part towards your digital section of the system
PCB. Care must also be exercised with placing the receiver in proximity to circuitry that can emit heat.
The RF part of the receiver is very sensitive to temperature and sudden changes can have an adverse
impact on performance.
⚠
High temperature drift and air vents can affect the GNSS performance. For best performance
avoid high temperature drift and air vents near the SiP.
2.14
EOS/ESD/EMI precautions
When integrating GNSS receivers into wireless systems, careful consideration must be given to
electromagnetic and voltage susceptibility issues. Wireless systems include components which can
produce Electrostatic Discharge (ESD), Electrical Overstress (EOS) and Electro-Magnetic
Interference (EMI). CMOS devices are more sensitive to such influences because their failure
mechanism is defined by the applied voltage, whereas bipolar semiconductors are more susceptible
to thermal overstress. The following design guidelines are provided to help in designing robust yet
cost effective solutions.
⚠
To avoid overstress damage during production or in the field it is essential to observe strict
EOS/ESD/EMI handling and protection measures.
⚠
To prevent overstress damage at the RF_IN of your receiver, never exceed the maximum input
power as specified in the
ZOE-M8B Data Sheet [1].
2.14.1
Electrostatic Discharge (ESD)
Electrostatic discharge (ESD) is the sudden and momentary electric current that flows
between two objects at different electrical potentials caused by direct contact or
induced by an electrostatic field. The term is usually used in the electronics and other
industries to describe momentary unwanted currents that may cause damage to electronic
equipment.
2.14.2
ESD protection measures
⚠
GNSS receivers are sensitive to Electrostatic Discharge (ESD). Special precautions are required
when handling.
Most defects caused by ESD can be prevented by following strict ESD protection rules for production
and handling. When implementing passive antenna patches or external antenna connection points,
then additional ESD measures as shown in Figure 19 can also avoid failures in the field.
