SuperMini nRF52840 Wireless Controller Development Board
SuperMini NRF52840 is a Nice!Nano alternative development board. All the pins are compatible with Nice!Nano, except P1.01/02/07 GPIOs broken out onto their own pins (see the footprint, it’s not compatible with those same three pins on the nice!nano). Its pins are the same as Pro Micro, which means it can be used with almost any Pro Micro compatible keyboard. SuperMini works wired and/or wireless via Bluetooth 5.0. The NRF5280 development board has a 3.7V lithium battery interface and a software switch that can cut off the power of the LED. When turned off, the standby power consumption is about ~1000uA (1mA) (nice!nano uses about ~20uA). SuperMini NRF52840 development board support ZMK Firmware.
nRF52840 is a high-performance, low-power wireless SoC chip launched by Norwegian Nordic Semiconductor. It supports multiple wireless protocols, including Bluetooth 5, Thread, Zigbee, ANT, and 2.4GHz. The nRF52840 chip uses an ARM Cortex-M4F processor, clocked at 64MHz, with built-in 1MB of flash memory and 256KB of RAM (same amount of flash memory and RAM as nice!nano). It also has a variety of peripherals, including ADC, PWM, SPI, I2C, UART, USB and GPIO, etc. In addition, nRF52840 also supports a variety of security functions, such as AES encryption, SHA-256 hashing and True Random Number Generator (TRNG).
SuperMini nRF52840 – default factory built-in program is Blink-All-IO (all IO ports automatically flip over in 1S). To enter into the controller Bootloader Please short-circuit RST to GND twice within 0.5S or just press the RST button twice on the keyboard board within 0.5 seconds.
SuperMini nRF52840 Parameters: – Bluetooth 5.0 – Microcontroller nRF52840 – ARM Cortex-M4F processor – Clocked at 64MHz – Flash Memory 1MB – RAM 256KB – Quiescent Current (power consumption at sleep mode 1mA – Battery charging chip: supports lithium battery charging and discharging – dual-current Li-Po charging with a jumper that you solder with max of 300mA (nice!nano supports up to 500mA) – software-controllable MOSFET on the VCC pin to cut standby current consumption of LEDs and other peripherals (in theory, i still need to test this) – nice!nano bootloader pre-flashed – low dropout current regulator (LDO): MICRONE(Nanjing Micro One Elec) ME6217C33M5G, with max output current 800 mA. Low current consumption during operation: 100uA and while turned off 1uA (spreadsheet data) – have seen users with Zephyr firmware and LDO enabled reaching 150uA power consumption, but it will turn off current to the external peripherals like Oled Screens, RGB Leds etc. If LDO is disabled it goes to about 800uA and sends current to the external peripherals. I still have to test this also.
SuperMini NRF52840 Pinout Diagram:
SuperMini NRF52840 Size dimensions:
External VCC control:
When P0.13 is set to low (disabled via firmware), the power supply to the 3.3V, VCC pin will be turned off. This is useful for reducing components that use power when idle (e.g. RGB, LEDs). Still needs to be tested.
Soldering your controller:
Avoid using non-regulated temperature irons, otherwise you risk to damage the controller or reduce it’s working life. Recommended Soldering Iron Temperature when soldering is 240 Celsius (464 Fahrenheit). Controllers are heat sensible and fragile components, please handle with care. ⚠️ When soldering the controller, avoid using high iron temperatures, as you could damage the main nRF52840 chip. A temperature around 270°C-300°C should be hot enough. The higher the temperature, the more likely you are to damage the board.
It’s also highly recommended that you socket your controller. To socket your controller you’ll need: a set of mill max pins + a set of controller sockets. Doing that offers ease of access to the battery and makes debugging your keyboard so much easier. If someday your controller dies or you accidentally break type-c port or anything else happens it just a matter of swapping it, instead of desoldering it from the PCB, risking to break the whole keyboard in the process. In short, it’s a small investment to save you lots of time and possibly money in the future. In most cases the battery should fit underneath the socketed controller. Be cautious of flipped controller with pins and other parts underneath (you don’t want to puncture your battery!)
To connect an external battery, you only need to solder the positive wire (normally red color) of the battery to B+ Pin on the controller and the negative wire (which is the ground and normally black color) to B- pin on the SuperMini controller. ⚠️ When soldering the wires please be careful not to short-circuit the positive and negative poles, otherwise you may burn the battery and equipment. Triple and then quadruple check that before, otherwise there is a risk of explosion 💥
If you want to connect to your controller a Li-Po Battery that is bigger then 500mAh, makes sense to short-circuit (connected between themselves, making a soldering bridge) the BOOST charging. This way the charging current increases from 100ma to 300ma. ⚠️Only do this if your Li-Po capacity is greater than 500mAh, otherwise there is a risk of explosion 💥
How to enter Bootloader and Flash SuperMini:
To enter into the controller Bootloader Please short-circuit RST to GND twice within 0.5S or just press the reset button twice on your keyboard within 0.5 seconds. On your operating system should appear an usb storage device called Nice!Nano. After compiling, using this tutorial, your ZMK firmware just drag and drop your .uf2 respective files into the storage device folder. After dropping/pasting the .uf2 files the folder will close itself and shown as the keyboard you compiled the firmware for, if it is the master side. If it slave side it will appear as unknown device.
Source: Controller manufacturer
For shipping time PLEASE check the FAQ page. Dismiss