Ublox ANNA-B4 Series, Руководство по системной интеграции, Страница: 12 / 74

ANNA-B4 series - System integration manual
UBX-21000517 - R03 Contents Page 12 of 74
C1-Public
2 System function interfaces
2.1 Main supply input
The power for ANNA-B4 modules is provided through the VCC pins. ANNA-B4 uses an integrated
DC/DC converter to transform the supply voltage presented at the
VCC pin into a stable system core
voltage. This makes ANNA-B4 modules compatible for use in battery-powered designs.
The VCC supply can be taken from any of the following sources:
• Switched Mode Power Supply (SMPS)
• Low Drop Out (LDO) regulator
• Battery
When using ANNA-B4 with a battery, it is important that the chosen battery can handle the peak
power of the module. In case of battery supply, consider adding extra capacitance on the supply line
to avoid capacity degradation. For information about voltage supply requirement and current
consumption, see also the respective ANNA-B402
[5] and ANNA-B412 data sheets [6] .
Digital I/O interfaces reference voltage (VCC_IO)
On ANNA-B4 modules, the I/O voltage level is the same as the supply voltage and VCC_IO is internally
connected to the supply input VCC .
When using ANNA-B4 with a battery, the I/O voltage level varies with battery output voltage. The
battery voltage depends on the battery “state of charge”. Level shifters might be needed to stabilize
the voltage – depending on the I/O voltage of the host system and interfacing components.
2.2 Antenna interface
ANNA-B4 is equipped both with an integrated chip antenna and an RF pin. The integrated chip
antenna makes ANNA-B4 suitable for a minimum sized application product. The RF pin enables use
of other antenna types. This could be either an antenna placed on the main PCB or an external
antenna.
ANNA-B4 supports the following antenna types:
• Integrated antenna included in ANNA-B4 SiP. The integrated antenna requires an external
counterpoise trace on the main PCB.
• Integrated antenna on the main PCB. Typically, a SMD antenna mounted on the main PCB, which
is connected to the ANNA-B4 RF pin through a transmission line.
• External Antenna. Typically, a dipole antenna connected to the ANNA-B4 RF pin through a coaxial
cable and U.FL connector on the main PCB.
Table 5 describes how the related pins shall be connected for each antenna solution
Pin External antenna, or
integrated antenna on
main PCB ANNA-B4 integrated antenna.
ANNA-B4 placed in the corner of
the main PCB ANNA-B4 integrated antenna.
ANNA-B4 placed along the side of
the main PCB
Pin 1 – ANT_PCB GND* GND pattern NC
Pin 2 – ANT_GND GND NC GND pattern
Pin 3 – ANT_GND GND NC GND pattern
Pin 5 – ANT_INT GND* Connect to pin 6 – ANT Connect to pin 6 – ANT
Pin 6 - ANT Connect to antenna or
antenna connector Connect to pin 5 – ANT_INT Connect to pin 5 – ANT_INT
*Connect to GND for better layout, not critical for function
Table 5: ANNA-B4 Antenna options