The SpeedyBee F405 AIO 40A Flight Controller is a powerful addition to the FPV world, offering a compact yet feature-rich package for 2″ to 5″ FPV drones. Recently, I reviewed the SpeedyBee Bee25, a cinewhoop powered by this very board, and its performance left a lasting impression. Today, we’ll dive into what makes the SpeedyBee F405 AIO stand out, its features, and whether it’s the perfect choice for your next build.
Learn about flight controllers in our buyer’s guide: https://oscarliang.com/flight-controller/
Table of Contents
Where to Buy
You can get the SpeedyBee F405 AIO FC from:
- AliExpress: https://s.click.aliexpress.com/e/_Ddxvpoh
- Banggood: https://oscarliang.com/product-i8d6
- Speedybee: https://oscarliang.com/product-oy45
The kit comes with useful accessories:
- USB-C Extension Board: Allows easy access to the USB port when the board is mounted inside the frame.
- LED Strip Power Distribution Board: Simplifies connecting multiple LED strips.
- External BEC: Ideal for powering VTX or other peripherals in a 6S setup.
- Hardware: Includes screws, extra grommets, and a large capacitor.
- Soldering Practice Board: Perfect for beginners looking to hone their soldering skills before working on the flight controller.
Specifications
FC Specifications:
- MCU: STM32F405
- Gyro: ICM-42688P
- USB Port Type: Type-C
- Barometer: SPA06-003
- OSD: Supported
- Bluetooth: Supported
- Wireless Firmware Update: Supported (no need to press the physical BOOT button)
- Wireless Blackbox Analysis: Not supported
- DJI Air Unit Connection:
- Supports 6-pin direct insertion and soldering
- Compatible with DJI O3/RunCam Link/Caddx Vista without changing wire order
- Flash (Blackbox): 8MB
- Betaflight CC Pads (Camera Parameter Adjustment): Supported
- Input Voltage: 3S-6S LiPo battery
- 4V5 Output: Two outputs, total 1A
- 5V BEC Output: Three outputs, total 2A (shared with 4V5)
- 9V BEC Output: None (external BEC module included, switchable between 5V and 9V; total 2A output)
- Motor Pads: M1-M4
- UART Ports:
- 4 full-function UARTs (UART3, UART4, UART5, UART6)
- SBUS (R2)
- ESC Telemetry: Not supported
- I2C: Supported
- LED Pads: Supported (for WS2812 LED control)
- Buzzer Pads: Supported (BZ+ and BZ- pads)
- BOOT Button: Supported (for DFU mode and firmware recovery)
- RSSI Pads: None
- SmartPort: Not supported
- Supported Firmware:
- BetaFlight (Default)
- INAV
- Firmware Target Name: SPEEDYBEE F405AIO
- Mounting: 25.5 x 25.5mm, 2mm hole diameter
- Dimensions: 33.0mm x 33.0mm x 8mm
- Weight: 13.6g (including CNC)
ESC Specifications:
- Input Voltage: 3-6S LiPo battery
- Continuous Current: 40A
- Burst Current: 45A (10 seconds)
- ESC Protocol: Supports DSHOT600/300 (use other protocols with caution)
- Output Voltage: VBAT battery voltage (to power the flight controller)
- Current Sensor: Supported (Scale = 254, Offset = 0)
- Firmware: Bluejay JH-40, 48kHz
Design and Build Quality
The SpeedyBee F405 AIO has a distinct look, with large purple heatsinks on both sides of the board. These aren’t just aesthetic—they improve cooling and provide added physical protection in crashes. The premium purple finish makes the board stand out compared to the more common black or green PCBs.
Despite its compact size of 33x33mm, the F405 AIO packs a punch. It’s small enough for 2″ builds, and it supports currents up to 40A, making it also suitable for up to 5-inch builds, provided you’re not pushing the motors to their absolute limits. The flight controller has built-in 5V 2A BEC and a 9V 2A BEC, which are perfect for powering LEDs, VTXs, and cameras. Additionally, its 25.5×25.5mm mounting holes make it compatible with a wide range of frames.
Weight and Size Considerations
Weighing 13.4 grams, the F405 AIO is slightly heavier than other AIO boards with similar specs, which usually weigh around 9 grams. The additional weight comes mainly from the heatsinks, adding around 3-4 grams. While this won’t impact cinewhoops or 5-inch FPV drones significantly, it could be a concern for ultra-light or sub-250g builds, where every gram matters.
Another consideration is its thickness. At 8mm, it’s thicker than most AIO boards, which can affect compatibility with compact frames. Be mindful of the FC height when replacing another AIO flight controller, as it might not fit all builds.
While the heat sinks enhance durability and cooling, they also cover many internal components, making it harder to identify certain pads. Thankfully, the included quick-start guide is comprehensive and highly useful. Keep it handy for soldering or troubleshooting.
Key Features
ESC Amp Rating
The SpeedyBee F405 AIO features a 40A 4in1 ESC, more than enough for the average 5-inch or smaller builds. The ESC comes pre-flashed with BlueJay firmware, supporting DShot300 and DShot600 protocols, enabling smooth motor performance and precise flight controls. Large motor pads make soldering straightforward, even for beginners.
4 UARTs
This flight controller offers 4 full UARTs for connecting peripherals such as GPS, ExpressLRS/Crossfire receivers, VTX, and more. There’s even an I2C connection, which is perfect for external compasses—ideal for iNav users or those looking to add more advanced navigation features.
Integrated Bluetooth
Just like SpeedyBee’s other flight controllers, Bluetooth is available on this board. Paired with the SpeedyBee app, you can wirelessly configure Betaflight settings, update firmware, and even flash the board—no laptop required.
USB-C Extension
One of the most thoughtful features is the USB-C extension board. While the FC has an onboard USB-C port, the breakout pads allow you to connect an external USB port and place it in a more accessible location within your frame. This is particularly helpful for cinewhoops with enclosed frames.
Integrated Blackbox Logging
For those running analog setups, the onboard OSD chip will display all the vital flight data right in your goggles. The board also features 8MB of Blackbox storage, which is essential for tuning your quad.
5V and 9V Dual BEC
The F405 AIO has dual BECs—a 5V 2A for powering your receiver and other 5V devices, and a 9V 2A specifically for your VTX. This is perfect for builds running digital systems like the DJI O3 Air Unit, ensuring stable power delivery even under heavy loads.
Accessories
The LED Pad Breakout Board makes soldering multiple LED strips easier by splitting the LED signal into four individual pads.
If the onboard BEC’s aren’t enough, they also included an external BEC which offers 9V or 5V output for additional power.
Areas for Improvement
While the large purple heat sinks improve cooling and durability, they have some downsides:
- Access Issues: The heatsinks partially cover several pads and boot button, making troubleshooting and soldering more challenging.
- Weight: The added weight (4–5 grams) could be a concern for ultra-light builds.
- Non-Removable Design: The heatsinks are glued on, making them extremely difficult to remove.
- No iNav Support, yet? In the specs it says it supports both Betaflight and iNav, but I have yet to find the target for this flight controller in the firmware flasher. Maybe in the next version?
In the Speedybee Bee25 BNF Cinewhoop, they used this exact F405 AIO FC without heatsinks. I wish they offered this heatsink-free version as well for the weight-conscious builders. Or they could change the way these heatsinks are mounted, for instance, instead of glue they could just use a couple of small screws.
Final Thoughts
At just $55, the SpeedyBee F405 AIO offers outstanding value, combining modern features with thoughtful design. Its Bluetooth integration, USB-C extension, and dual BECs make it one of the most user-friendly AIO flight controllers available today. The high-quality build and premium look, coupled with excellent performance, set it apart in its price range.
Whether you’re building a cinewhoop, a freestyle quad, or an iNav GPS drone, the SpeedyBee F405 AIO is a fantastic choice. It’s ideal for those who want a balance of performance, reliability, and ease of use.
You can get the SpeedyBee F405 AIO FC from:
- AliExpress: https://s.click.aliexpress.com/e/_Ddxvpoh
- Banggood: https://oscarliang.com/product-i8d6
- Speedybee: https://oscarliang.com/product-oy45
13 comments
HI Oscar,
I was wondering if you successfully connected a DJI O4 Air Unit to this flight controller? I put a 2.5″ drone together intending for a 4s set-up with this flight controller, hooked up a Happymodel ELRS receiver, did the usual set-up on Betaflight, and did a test flight MINUS a VTX. Everything powered up like normal and I was able to get it fly. Once I finally got the O4, I completed a firmware update and plugged it in this FC and no power. At first I thought it was my connections, but everything checked out. I also tried using the BEC that came with the FC, 5V and 9V, and still no go. I had a spare O3 laying around, when I plugged it in, POWER! I was wondering if you or anyone else maybe having the same issue?
Hey Oscar. you write that the AIO has on-board 9V BEC, but thats not true, it only has external 9V BEC. I just found it out and was kind of surprised 😅
Oscar, do you know if I could mount an o4 (non pro) on this board?
Thanks!
You can, but you must use the provided BEC board, and you should bridge the 5V pad on it so the BEC board outputs 5V to power the O4 Air unit.
Great Review, thanks! If my stack breaks, I will try this AIO for my 3.5″ Build. But I don’t think there is a 9V BEC Built in as you metioned in the “Design and Build Quality” section?
The BEC is on a separate board as shown in the picture, it has 5V/9V pads which you have to bridge to choose which output voltage you want.
Thanks for a great review from you, again🙂
I am just about done building this with the f405 40a aio but I used the uart 5 for the ext board and uart 6 for elrs. The uart 3 is the same as the dji plug use. I cant fint the T4. So as far as I see it is just 3 full functions uarts. An sbus/r2 and a r4. Which means I dont get to solder on my gps to a uart.. I am new to this, so correct me if I am wrong.
Yeah, I don’t see how to connect the fourth UART either, only RX4. Where is TX4?
T4 is under the corner of the heatsink near R4
I’m wondering how to apply conformal coating for this type of Controller(with the heatsinks) ?
Just cover all exposed parts and that’s all?
Thanks!
If you manage to seal all the gaps between the heatsink and the PCB, maybe. But it’s best to apply conformal coating with the heatsink removed. But it will impact cooling as the coating will keep the heat in.
The Bee25 board is an Speedybee F405 AIO 35A. It is not compatible with INAV. Resource for motor are different. No INAVtarget for SPEEDYBEEF405AIO 35A
I purchased 2 of these and am using one on a 2s long-range build and it works fine! I did not think it would power on at all, but no issues. I love the build-in bluetooth for configuring it. This AIO is an awesome value.