MDBTMicro
MDBTMicro-50Q is an alternative board to nRFMicro/Pro Micro.
It has USB Type-C and LiPo charger, uses Raytac MDBT50Q-x1MV2 nRF52840 module (or MDBT50Q-x512K nRF52833 module) instead of E73-2G4M08S1.
Go to Releases for schematic and Gerber files.
A part of ErgoSNM keyboard project.
EDA: KiCad
PCB
| Front | Back | Layers |
|---|---|---|
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 |
 |
BOM
| Designator | Value | Footprint |
|---|---|---|
| C1,C2 | 1uF | 0603 (1608 Metric) |
| C3,C4 | 12pF | 0603 (1608 Metric) |
| R1 | 100k | 0603 (1608 Metric) |
| R2,R4 | 1k | 0603 (1608 Metric) |
| R3 | Rprog | 0603 (1608 Metric) |
| R5 | 1k | 0402 (1005 Metric) |
| R6 | 820k | 0603 (1608 Metric) |
| R7,R8 | 2M | 0603 (1608 Metric) |
| R9,R10 | 5.1k | 0603 (1608 Metric) |
| D1 | 1N5819 | SOD-323F |
| J2 | USB_C_Receptacle_USB2.0 | 918-418K2024S40000 |
| LD1 | Red | 0603 (1608 Metric) |
| LD2 | Blue | 0603 (1608 Metric) |
| LD3 | Green | 0402 (1005 Metric) |
| Q1,Q2 | AO3407 | Package_TO_SOT_SMD:SOT-23 |
| U1 | XC6220B331MR-G | SOT-23-5 |
| U2 | MDBT50Q-x1MV2 | MDBT50Q |
| U3 | TP4057 | SOT-23-6 |
| X1 | 32.768kHz | 2Pin 3.2x1.5mm |
- Please note that the footprint of R5 and LD3 is 0402.
- R2, R3, U3 and LD1 are not necessary if LiPo charger is not required.
- R6 and R7 are not necessary if LiPo battery monitor is not required.
- Adjust the LiPo charging current with the value of R3.
- 20 kΩ: 50 mA
- 10 kΩ: 100 mA
- 5 kΩ: 200 mA
- 4 kΩ: 250 mA
- 3 kΩ: 300 mA
- 2 kΩ: 400 mA
- 1.6 kΩ: 500 mA
- XC6220B331MR-G can be replaced by AP2112K-3.3.
- MDBT50Q module includes MDBT50Q-1MV2/P1MV2/U1MV2 (nRF52840-based), or MDBT50Q-512K/P512K/U512K (nRF52833-based).
There is not designator silkscreen on PCB, please use your browser to open the ibom.html file (placed in release page) to refer to the placement of the parts, it is generated by Interactive HTML BOM plugin.
Pinout
MDBTMicro-50Q 1.4 |
nRFMicro 1.4 |
Pro Micro | <--> | Pro Micro | nRFMicro 1.4 |
MDBTMicro-50Q 1.4 |
|---|---|---|---|---|---|---|
| GND | GND | -- | -- | VBAT | VBAT | |
| P0.06 | P0.06 | D1/Tx | RAW | VBAT | VBUS (USB 5V) | |
| P0.08 | P0.08 | D0/Rx | GND | GND | GND | |
| GND | GND | GND | RST | P0.18/RESET | P0.18/RESET | |
| GND | GND | GND | VCC | VDD & VDDH | VDD & VDDH | |
| P0.15 | P0.15 | D2 | A3 | P0.30 | P0.30 | |
| P0.17 | P0.17 | D3 | A2 | P0.31 | P0.31 | |
| P0.20 | P0.20 | D4 | A1 | P0.29 | P0.29 | |
| P0.13 | P0.13 | D5 | A0 | P0.02 | P0.02 | |
| P0.24 | P0.24 | D6 | D15 | P1.13 | P1.13 (P1.05) | |
| P0.09 | P0.09 | D7 | D14 | P0.03 | P0.03 | |
| P0.10 | P0.10 | D8 | D16 | P0.28 | P0.28 | |
| P1.06 | P1.06 | D9 | D10 | P1.11 | P1.11 (P1.04) | |
| P1.10 (P0.25) | P1.10 | -- | LED Pin | |||
| P0.04 | P0.04 | -- | Battery Pin | |||
| P1.09 | P1.09 | -- | Power Pin | |||
| P1.12 (P0.23) | -- | -- | TP1 | |||
| P1.14 (P1.03) | -- | -- | TP2 | |||
| P1.15 (P0.19) | -- | -- | TP3 | |||
| P0.05 | -- | -- | TP4 | |||
| P0.07 | -- | -- | TP5 | |||
| P0.11 | -- | -- | TP6 | |||
| P0.12 | -- | -- | TP7 |
Italics in brackets for MDBT50Q-x512K (nRF52833) pins, otherwise MDBT50Q-x1MV2 (nRF52840).
Almost the same as nRFMicro 1.4
Jumper Config
- JP1
- nRF52840: Open
- nRF52833: Close
Board Characteristics
- Copper layer count: 2
- Board overall dimensions: 33.02 mm x 17.78 mm (1.3 x 0.7 inch)
- Min track/spacing: 0.127 mm / 0.127 mm
- Min hole diameter: 0.3 mm
Disclaimer
These files without warranty of any kind, use at your own risk, it is recommended to check yourself before manufacture.
For the full statement, please see LICENSE.