AMY-6M - Hardware Integration Manual
UBX-17021971 – R07
Design-in
Page 12 of 57
Supply Voltage [V]
LDO [mW]
Single 1.8V DCDC Converter [mW]
1.8
85
106
2.5
118
106
3
141
106
3.3
155
106
4.2
197
106
5
235
106
Table 3: Acquisition Power Consumption (ECO Mode)
Some conclusions from Table 1 to Table 3:
The most efficient solution is to have a direct 1.4 V / 1.8 V supply available from the system. The respective
application circuit is shown in section 2.1.7
If a 1.8V supply is available the best solution is to supply RF and BB part directly. The respective application
circuit is shown in section 2.1.6.
For supply voltages above 2.5 V, a DC/DC converter having a 1.8 V output voltage should be used for good
efficiency. The respective application circuit is shown in section 2.1.9.
Using only the built-in LDOs of u-blox 6 at supply voltages between 2.5 V and 3.6 V is not efficient but very
cost effective in terms of BoM. The respective application circuit is shown in section 2.1.5
2.1.4
How to connect the power supply pins
Table 4 lists the power supply pins and their connection requirements.
Pin
Function
Comments
V_DCDC
Main Core (VDD_C) Supply
Always needs input. The current consumption varies over time (peak currents).
Keep series resistance low to prevent ripple on the power supply.
VDD_3V
Main RF Supply
Supplied by 2.5…3.6V or connected to VDD_RF, depends on supply scheme.
VDD_IO
I/O Supply Voltage
Always needs to be supplied.
V_BCKP
Backup voltage (VDD_B) supply
Connect to GND if not used.
VDD_B
Backup Core Voltage
Leave open.
VDD_C
Main Core Voltage
Leave open.
VDD_RF
RF Core Supply Voltage
Leave open or must be supplied by 1.75…2.0V, depends on supply scheme.
In case of supplied by 1.75…2.0V it also has to be shorted to VDD_3V.
VDD_ANA
Analog Power
Leave open.
VDD_LNA
LNA Power Supply
Leave open.
V_RESET
RESET input
Connect to supervising voltage, mostly to VDD_3V (see 2.1.1.6)
V_TH
Sets Threshold for V_RESET
V_TH = open: V_RESET supervised voltage at nominal 1.8 V.
V_TH= GND: V_RESET supervised voltage at nominal 2.5 V and above.
DCDC_EN
Enable for external DCDC
converter
Leave open if not used. Otherwise connect to enable pin of external DCDC
converter.
VDD_USB
Supply for USB interface
Connect to GND if not used.
Table 4: Power Supply Pins
