Digi ConnectCore 6UL Hardware Reference Manual page 12

About the ConnectCore® 6UL
Powering the system for battery-powered applications (3.7V - 4.5V)
Note In the implementations shown above, the coin cell/supercapacitor is connected to VCC_LICELL
pin of the ConnectCore 6UL module, allowing coin-cell charger applications. This VCC_LICELL
connection feeds the VSNVS regulator of the PMIC, which supplies the SNVS power domain of the
CPU. The VSNVS regulator derives its power from either VIN or the coin cell (VIN takes precedence),
and it cannot be disabled. This power domain allows some functionality of the CPU in low power mode
applications even when the main power supply of the system is removed. However, this connection
significantly increases the power consumption of the module in these low-power modes. This explains
the power consumption in power-off mode; see
To optimize power management in coin cell applications:
Do not connect the coin cell/supercapacitor to the VCC_LICELL power domain. You must keep the
connection to VCC_MCA. This drastically reduces power consumption and extends the life of the
power supply. To preserve coin cell charger functionality, follow the instructions in the
section.
The power architecture of the module is described in more detail below.
The PMIC generates the following power domains that are available on the module pads:
Buck converters. Two buck regulators provide 3.3V:
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SW1A: 3V3_INT, powers several interfaces inside the module
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SW2: 3V3_EXT, free power line not used inside the module
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And another two buck regulators used for internal supply:
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SW1B: VDD_ARM_SOC_IN
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SW3: VCC_DDR3
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ConnectCore® 6UL Hardware Reference Manual
Global power consumption
Power interfaces
for more information
Coin cell
12