Building our own micro:bit robot kit.
Requirements:

• powered by a mini 5V USB powerbank (e.g. 2000 - 3000 mAh),
• The Micro:Bit power input is 3.3V regulated, via the 3V skrew connector (conductive holes),
• driving two SG90 micro servo motors (360°) with wheels (not the yellow DC motors), powered by 5V
• level shifter for the servo control signal from Micro:Bit 3.3V to 5V for the servos
• driving at least one additional servo motor (360° or 180°) for further action,

Pictures from the Keystudio Wiki:
https://wiki.keyestudio.com/MB0102_Keyestudio_Microbit_Main_Board_%2BUSB_Cable%2BBattery_Holder_with_Batteries

• https://github.com/microbit-foundation/microbit-v2-hardware
• microbit_v2.2.1_nrf52820_schematic.pdf

• out: Vout = 3.3V fixed,
• in: Vin = 5.5V max,
• current: Imax = 300mA
• datasheet: NCP114BMX330TCG

NOTES:
Read the annotations on the regulator schematic! The board can have FOUR power input sources.

1. 5V USB via USB connector
2. 3V - 4.5V via battery connector (skrew terminals)
3. “lozenge” (Pastille, Raute) shaped power pad, connected to Vout of NCP114
4. 3V - 5V typ. from edge connector

It is weird that the power input from the edge connector is directly connected to the voltage output pin of the LDO! Do I (rb) understand this correctly?

• lsm303agr.pdf

• no power regulator
• no motor drivers
• just a buzzer
• works for V1 and V2
• https://www.electroschematics.com/microbit-2/

• voltage regulator 5V → 3.3V
• logic level shifter
• https://wiki.keyestudio.com/KS4030_Keyestudio_Microbit_Expansion_Board

ATTENTION: 180° ONLY!

Original source: https://www.monkmakes.com/mb_servo_kit

Distributors:
RS Online: https://de.rs-online.com/web/p/bbc-micro-bit-add-ons/2048260
RobotShop: https://eu.robotshop.com/products/servo-controller-microbit-monk-makes
okdo: https://www.okdo.com/de/p/servo-kit-for-microbit/

https://www.monkmakes.com/mb_servo_kit

https://eu.robotshop.com/de/products/servo-controller-microbit-monk-makes

Original source: https://kitronik.co.uk/products/5673-kitronik-simple-servo-control-board-for-bbc-micro-bit

https://kitronik.co.uk/products/5673-kitronik-simple-servo-control-board-for-bbc-micro-bit

• Datasheet: 5673-kitronik-create-simple-servo-control-board-datasheet.pdf

Distributors:

• RS Online: https://de.rs-online.com/web/p/bbc-micro-bit-add-ons/2663768
• RobotShop: https://eu.robotshop.com/products/kitronik-simple-servo-control-board-for-bbc-microbit
• …

Original source: https://kitronik.co.uk/products/5694-compact-16-servo-driver-board-for-the-bbc-micro-bit

Datasheet:
5694-kitronik-compact-16-servo-driver-board-for-microbit-datasheet.pdf

Features:

• Operating Voltage (Vcc): 3V to 12V
• Number of Servo channels: 16
• Servo Voltage: Same as input Voltage
• Max continuous current (all servos): 10A

ATTENTION: 180° ONLY!

Distributors:
AZ-Delivery: https://www.az-delivery.de/en/products/az-delivery-micro-servo-sg90?variant=12236813336672