UBX-G7020 - Hardware Integration Manual
Design-in
GPS.G7-HW-10003
Objective Specification
Page 18 of 74
At initial start up in production, the UBX-G7020 will not have information about the supply voltage or oscillator
settings required and hence may not be able to start up without this information. Hence an initial power-up
requires starting in Safe Boot Mode in which the receiver runs from an internal ring oscillator. Then the Low
Level Configuration can be set in the eFuse or in the SQI flash. See section 2.2.6 and section 2.10.2.
Make sure the SAFEBOOT_N pin (PIO12) is made available to enter the Safe Boot Mode, a pre-requisite
to program the flash and preset the Low Level Configuration in production.
2.2.2
Configuration pins
If no SQI flash is connected, there is a configuration enabling pin (PIO5) which activates 5 configuration pins
PIO0 to PIO4. These pins allow setting some essential oscillator and power supply (DCDC converter)
configurations.
PIO5 connected to GND will enable configuration pins at PIO0 to PIO4!
PIO0 is reserved and must be left open when no SQI Flash is employed.
All the configuration pins have internal pull-ups. Any left open equates to a logical “1”.
PIO5
Configuration
Remarks
1
(open)
Configuration pins disabled
The configuration done by PIO0 to PIO4 is ignored.
0
(GND)
Configuration pins
enabled
Table 2: Enable configuration pins
PIO1
Configuration
Remarks
1
(open)
DCDC converter disabled
0
(GND)
DCDC converter enabled
Requires additional circuitry
Table 3: DCDC converter configuration pin
PIO2
PIO3
PIO4
Configuration
Remarks
1
(open)
1
(open)
1
(open)
Crystal 19pF load
0
(GND)
1
(open)
1
(open)
Reserved
1
(open)
0
(GND)
1
(open)
Reserved
0
(GND)
0
(GND)
1
(open)
Reserved
1
(open)
1
(open)
0
(GND)
LDO_X_OUT = 3.01V
LDO_X_OUT supplies and enables the 3V TCXO.
0
(GND)
1
(open)
0
(GND)
LDO_X_OUT = 1.91V
LDO_X_OUT supplies and enables the 1.8V TCXO.
1
(open)
0
(GND)
0
(GND)
LDO_X_OUT = 2.69V
LDO_X_OUT used to enable the 3V TCXO; TCXO supplied directly by
same voltage as used to supply VDD_IO.
0
(GND)
0
(GND)
0
(GND)
LDO_X_OUT = 1.67V
LDO_X_OUT used to enable the 1.8V TCXO; TCXO supplied directly
by same voltage as used to supply VDD_IO.
Table 4: Oscillator configuration pins
For oscillator circuits and recommendations see section 2.4!
PIO0 is reserved for further use. Leave it open.
For further information about the Low Level Configuration of the UBX-G7020 see section 2.10.2.
