ZOE-M8 series - Hardware integration manual
UBX-16030136 - R09
Design-in
Page 6 of 34
Production information
2
Design-in
To obtain good performance with ZOE-M8 GNSS receiver SiPs, there are a number of issues requiring
careful attention during the design-in. These include:
Power supply: Good performance requires a clean and stable power supply.
Interfaces: Ensure correct wiring, rate and message setup on the SiP and your host system.
Antenna interface: For optimal performance, seek short routing, matched impedance and no
stubs.
2.1
Power management
The ZOE-M8G is a 1.8 V variant, while the ZOE-M8Q is a 3.0 V variant and has an option to make use
of the built-in DC/DC converter to reduce the power consumption.
The ZOE-M8 GNSS SiPs provide two supply pins: VCC and V_BCKP. They can be supplied
independently or tied together, depending on the intended application.
Additionally, ZOE-M8Q has the option to make use of a built-in DC/DC converter and thus comes with
two additional supply pins, V_CORE and V_DCDC_OUT. The supply voltages are explained in the
following subsections.
2.1.1
Main supply voltage (VCC)
During operation, the ZOE-M8 GNSS SiPs are supplied through the VCC pin. Built-in LDOs generate
stabilized voltages for the core and RF domains of the chip, respectively. The current at VCC depends
heavily on the current state of the system and is in general very dynamic.
☞
Do not add any series resistance (< 0.1
Ω
) to the VCC supply, as it will generate input voltage noise
due to the dynamic current conditions.
The digital I/Os of the ZOE-M8 GNSS SiPs are also referred and supplied to the VCC voltage.
2.1.2
V_CORE (only on ZOE-M8Q)
V_CORE draws the main current of the ZOE-M8Q. The current at V_CORE depends heavily on the
current system state and in general exhibits very dynamic behavior. It can be supplied either by main
supply or with the built-in DC/DC converter, see section 2.1.3.
☞
Do not add any series resistance greater than 0.1
Ω
to the V_CORE supply as it will generate input
voltage noise due to the dynamic current conditions.
☞
If a DC/DC converter is not used, supply V_CORE with the same supply as used for the VCC.
2.1.3
DC/DC converter (only on ZOE-M8Q)
ZOE-M8Q comes with a built-in DC/DC converter to supply V_CORE, thus enabling significant power
savings. For more information, see the ZOE-M8 Data sheet [1]. It requires an external inductor (L1)
and capacitor (C1). For the recommended inductor and capacitor, see Appendix A.4 and Appendix A.9.
