UBX-G7020 - Hardware Integration Manual
Design-in
GPS.G7-HW-10003 Objective Specification Page 44 of 74
In case SPI is used for communication to host, UART can be
remapped to PIO15 and PIO16 if needed
Remapped UART
cannot be used in
Safe Boot Mode!
Sets the threshold for the VDD_IO POR. The VDD_IO POR
threshold needs to be set according to supply voltage range of
external SQI Flash (1.8V / 3V).
Must be always
configured in
eFuse!
Enables the optional DCDC converter
RTC is derived from Main Clock (no RTC crystal needed)
What kind of clock source is used; TCXO or Crystal
Additional information to the clock source; load of crystal or
supply of TCXO
Antenna
supervisor/ external
LNA enable pin
There are 2 different antenna supervisors available, a 2-pin and
a 3-pin version. Additionally on enable signal can be made
available to turn off external LNA in Power Save Mode.
Polarity of Antenna
supervisor / LNA
enable pin
Polarity of the antenna supervisor pins/ LNA enable pin can be
configured.
Self or bus powered device
u-blox AG - www.u-blox.com
u-blox 7 - GPS/GNSS Receiver
Table 12: Low Level Configuration overview and default settings
For detailed information about how to set the Low Level Configuration in SQI flash or eFuse see u-blox 7
Receiver description including protocol specification [3].
The VDD_IO threshold (POR_IO) which has to match the supply voltage of the SQI flash, must be always
configured in eFuse; must not be set in SQI Flash!
The current Low Level Configuration can be checked by polling the UBX-MON-LLC message, see u-blox 7
Receiver description including protocol specification [3].
2.10.2.1 One Time Programmable eFuse
The UBX-G7020 eFuse is implemented as an OTP memory which can hold all the Low Level Configuration
settings. The eFuse is supplied by VDD_IO and consumes ~10mA during writing.
The eFuse can be accessed and changed by any communication port. To write a Low Level Configuration into
the eFuse, the UBX-CFG-OTP message has to be used. For detailed information see u-blox 7 Receiver description
including protocol specification [3].
In Safe Boot Mode (e.g. in production for designs with external SQI flash) the eFuse cannot be accessed by USB,
because of the unknown main clock source, see section 2.2.6. Access via UART is possible after sending a
training sequence to the UBX-G7020. With a remapped UART it is not possible to communicate to the UBX-
G7020 in Safe Boot Mode. A DDC and SPI communication method is the most convenient mode to set the eFuse
Low Level Configuration correctly as the clock is provided by the host.
VDD_IO monitor level (POR_IO) level must always be set in eFuse!
2.10.2.2 Low Level Configuration by Configuration Pins (for designs without external SQI Flash)
If no external SQI Flash is connected, PIO0 to PIO5 can be used for some low level configuration settings. If PIO5
(CONFIG_SEL), is connected to GND it enables the Low Level Configuration pins PIO0 to PIO4. The part of the
Low Level Configuration set by the configuration pins has a higher priority than the Low Level Configuration
held in the eFuse. For information about the Low Level Configuration pins see section 2.2.2.