Data Sheet
Table Of Contents
- Document information
- Contents
- 1 Functional description
- 2 Pin definition
- 3 Electrical specifications
- 4 Firmware
- 5 Mechanical specifications
- 6 RF design notes
- 7 BMD-380 evaluation development kit
- 8 Qualification and approvals
- 9 Environmental
- 10 Product handling
- 11 Ordering information
- 12 Life support and other high-risk use warning
- Related documents
- Revision history
- Contact
BMD-380 - Data sheet
UBX-19039467 - R06 Electrical specifications Page 13 of 36
3.3 Power and DCDC configuration
☞ The BMD-380 is based on the nRF52840, revision 2 or newer IC.
The BMD-380 has two internal regulator stages that each contain an LDO and DCDC regulator. The
first regulator, REG0, is fed by the VCCH pin and can accept a source voltage of 2.5 V to 5.5 V. The
output of REG0 is connected to the VCC pin and the input of the second regulator stage REG1. REG1
supplies power to the module core and can accept an input source voltage of 1.7V to 3.6V. Depending
on how the VCC and VCCH pins are connected, the module will operate in one of two modes:
Normal/Low Voltage (LV) or High Voltage (HV). The voltage present on the VCC pin is always the GPIO
high logic level voltage, regardless of power mode.
To enter LV Mode, the same source voltage is applied to both the VCC and VCCH pins causing REG0
to automatically shut down leaving only the REG1 stage active. To enter HV, the source voltage is only
applied to VCCH causing the VCC pin to become an output source supplied by REG0.
Mode
Pin
Name
Connection
Normal (LV)
24
22
VCC
VCCH
1.7V to 3.6V source in
Same source as VCC
High Voltage (HV)
24
22
VCC
VCCH
1.8V to 3.3V supply out
2.5V to 5.5V source in
Table 7: Power mode pin connections
⚠ Important: In both LV and HV modes, the GPIO logic level voltage is determined by the VCC pin. In
HV mode, all external devices that are connected to the BMD-380’s GPIO must either be powered
by the module (from VCC) or use level translation.
REG0 can supply a maximum current of 25mA for the module and external circuits in System On Mode
and 1 mA in System Off Mode. External circuits powered from VCC in HV mode should be limited to
no more than 5 mA to ensure stability at all radio transmit power levels.
3.3.1 USB power
The USB interface on the BMD-380 can be used when the module is in either Normal (LV) or High
Voltage (HV) mode. The BMD-380 USB PHY is powered by a dedicated, internal LDO regulator that is
fed by the VBUS pin (66). This means that applying power to only the VBUS pin will not power the rest
of the module. In order for the USB PHY to operate, VBUS must be externally powered.