User's Guide
Page 14 of 19
nBlue Bluetooth 5.0 Module User’s Guide
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2.3.13 Power Modes
** IMPORTANT **: The module can be powered in normal voltage mode (1.7-3.6V) or high voltage mode (2.5-5.5V).
In normal voltage mode, 1.7-3.6V must be connected to both VDD and VDDH. In high voltage mode, 2.5-5.5V is
connected only to VDDH and in this case VDD will be the output of the internal VDDH regulator (AT.s firmware
sets the VDDH output to 3.3V, but the 52840 defaults to 1.8V). In either power mode the voltage on the VDD pin
will be the IO voltage, so the IO voltage can never be higher than 3.6V and is never 5V tolerant even when using
VDDH. See the Internal Regulator Diagram on the next page for a visual on how the regulators connect.
** IMPORTANT **: Due to an issue with Rev 1 of the nRF52840, high voltage mode can only be used under the
following conditions: the VDDH internal DCDC converter cannot not enabled (default LDO mode only), no current
is drawn from the VDD pin during power up and the VDDH rise time to 3V is < 1ms. This will be fixed in the next
nRF52840 revision. See Errata 197 and 202 of the nRF52840 Rev 1 Errata for more info:
http://infocenter.nordicsemi.com/pdf/nRF52840_Rev_1_Errata_v1.1.pdf
* VBUS *: To use the BR-LE5.0-S1A as a USB peripheral, 5V must be supplied on the VBUS pin. The VBUS supply is
internally regulated to 3.3V but is only used for the USB signaling interface and USB detection. The rest of the USB
peripheral is powered through the main power supply, so power must still be supplied through VDDH or VDD depending
on what power mode is being used. When supplying power from a USB source only, VBUS must be connected to VDDH
if USB is to be used.
INTERNAL REGULATOR DIAGRAM
Note: The inductors required to use the nRF52840’s DC/DC converters are populated inside the module - no external
inductors are required. With the AT.s firmware, the REG1 DC/DC is automatically enabled.