Supply Interfaces; Main Supply Inputs - Ublox JODY-W1 Series System Integration Manual

1.3 Supply interfaces

1.3.1

Main supply inputs

JODY-W1 series modules must be supplied through the VBAT/VIO/VIO_SD pins. All supply voltages
used inside the modules are generated from the VBAT rail through internal DC/DC converters.
The current drawn by the JODY-W1 series through the VBAT pin can vary by several orders of
magnitude depending on the operation mode and state. In connected mode, high-current
consumption is expected at a maximum RF power level during Wi-Fi transmission. With the power
saving configuration enabled, low current consumption is expected in the low power idle mode.
Supply voltages and other electrical requirements are shown in the JODY-W1 series data sheet [2].
Rail Allowable ripple (peak to peak)
10-100 kHz
VBAT (3.3 V) 65 mV
VIO + VIO_SD 65 mV
Table 4: Summary of voltage supply requirements
The JODY-W1 series modules can be powered by one of the following DC supplies:
•
Switching Mode Power Supply (SMPS)
•
Low Drop Out (LDO) regulator
The SMPS is the ideal choice when the available primary supply source has higher value than the
operating supply voltage of the JODY-W1 series modules. The use of SMPS provides the best power
efficiency for the overall application and minimizes current drawn from the main supply source.
⚠
While selecting the SMPS, ensure that the AC voltage ripple at switching frequency does not
violate the requirements as specified in
impact of high frequency ringing. See also
switching regulator.
The use of an LDO linear regulator is convenient for a primary supply with a relatively low voltage
where the typical 85-90% efficiency of the switching regulator leads to minimal current saving. Linear
regulators are not recommended for high voltage step-down as they will dissipate a considerable
amount of energy.
Independent of the selected DC power supply, it is crucial that it can handle the high peak current
generated by the module. It is recommended to provide at least 20% margin overstated peak current
when designing the power supply for this module.
2 Ripple measured on the power connectors of u-blox EVK.
UBX-16012621 - R18
C1-Public
2 over DC supply
100 kHz-1 MHz
25 mV
pk-pk pk-pk
25 mV
pk-pk pk-pk
System description
JODY-W1 series - System integration manual
>1 MHz
10 mV
pk-pk
10 mV
pk-pk
Table 4. Layout shall be implemented to minimize the
Guidelines for VCC supply circuit design using a
Current consumption, peak
Wi-Fi: 1050 mA
BT: 60 mA
400 µA
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