The Betaflight F7 flight controller has just arrived! FPVModel fixed a lot of the issues in the Betaflight F4 board, and added many new features and capability in the new FC. In this review we will take a close look at the board.
Specs and Features of the Betaflight F7 FC
- Integrated PDB
- Two on-board IMU: MPU6000 and ICM20608
- Input Voltage 3S-6S
- 4 UART’s (all have built-in inverters)
- 5V BEC 1.2A
- Betaflight OSD
- Current Sensor (supports up to 145A)
- 16MB Flash memory for blackbox
- Supports TBS Crossfire & Telemetry
- Supports Frsky SBUS & SmartPort without inversion hack
- Dedicated pins for ESC telemetry
- Dedicated pin for FPV Camera Control
- Firmware Target: BetaflightF7 (BFF7)
Betaflight F7 VS Betaflight F4
Here is the comparison between the Betaflight F7 and F4 flight controllers in terms of features and improvements.
Check out the full review of the Betaflight F4 FC.
|Betaflight F7||Betaflight F4|
|Price||$60||$45 (on sale now for $34)|
|ESC Connection||Only on top the board (thanks god!)||On both sides of the board|
|BEC||5V, 1.2A||5V, 1.5A|
The F7 is a more powerful processor than the F4, but right now the advantage in processing power is not a big deal because we haven’t used up all the resources on the F4 yet. The biggest difference for me is the number of UART’s, you get 1 more on the Betaflight F7 than the F4, and you won’t have to worry about getting the uninverted signal for SBUS or SmartPort because all the UART’s has built-in inverters in the F7 processor.
The solder pads style and layout on the Betaflight F7 look similar to the CLRacing F4 FC, and I think that’s a good direction to take. The solder pads are good sized and look to be really easy to work with :)
Finally I am excited to see they have finally moved the ESC power pads to the top of the FC, it was such a difficult task with soldering on the F3 and F4, where the ESC power was on the bottom of the board while the ESC signal was on top.
Closer Look at the Betaflight FC Board
So far, the improvement and spec we have mentioned above seem excellent.
The most interesting update on the Betaflight F7 is the two onboard gyro sensors: the MPU6000 and the ICM20608. However, don’t get your hopes up, it’s not a “dual gyro stabilization”, these are just options you can choose to use.
Surely having two gyros on the same board will increase the cost, but this might make this board more future proof. Right now most people are happy running 8KHz looptime, using the MPU6000 is enough. But future Betaflight development might benefit from a faster Gyro such as Kalman Filter.
Another drawback of the soft-mounted ICM20608 Gyro is the added height of the board and increased weight. The height of the board is only 5.3mm, but with the gyro protective case it adds another 5mm to it, making it a total of about 10mm.
The board weighs a total 12g, and only 9.6g without the ICM2068 gyro (it’s removable which I will show you in a moment).
The MPU6000 is the “good one” that provides more reliable performance up to 8KHz sampling rate. The ICM20608 allows you to run 32KHz gyro sampling rate but it’s known to be susceptible to noise, I guess that’s why this gyro is soft mounted in a plastic protective case (same approach is used in the Kakute F4). (The MPU6000 is hard-mounted on the board, that’s why the FC comes with rubber grommets).
You can choose which gyro to use by entering commands in CLI:
To use the MPU6000,
set gyro_to_use = 0 save
To use the ICM20608,
set gyro_to_use = 1 save
If you don’t like the ICM20806 gyro, or the idea of using a ribbon cable to connect the gyro, you can just remove it and use the surface-mounted MPU6000.
The ribbon cable is connected with a connector and removable. There are 4 screws on the back of the board that hold the gyro protective case in place.
The board works as normal without the ICM20806, putting it back on the board and it still works as normal :)
The advantage of removing the ICM20806 is lower profile by about 5mm, and reducing the weight by 2.5g.
This is kind of cool… but I also feel a bit messed up because you paid extra for it and now you want to remove it :) Maybe the extra ICM20806 gyro should have been a option when purchasing the board?
Testing and Review
Beware that there is currently still no firmware target available for the board on Github, and therefore you won’t find the board in the firmware flasher in the configurator when you try to update it. Hopefully this will be fixed soon.
I plan to test this board in a quad soon, stay tuned!