SpeedyBee F405 V4 BLS 55A 30x30 FC & ESC Stack

The SpeedyBee F405 V4 stack pairs an STM32F405 flight controller with a BLS 55A 4-in-1 ESC on the standard 30.5 x 30.5 mm pattern, for 5- to 7-inch freestyle, racing and long-range quads on 3-6S LiPo. Built-in Bluetooth lets you set up the flight controller from the SpeedyBee app at the field, without a laptop.

Key features

• ICM42688P gyro, onboard barometer and AT7456E chip for analogue OSD
• Six UARTs, with UART4 reserved for Bluetooth and UART5 for ESC telemetry, leaving four for receiver, GPS and VTX
• MicroSD card slot for blackbox logging
• 5 V (nine pads) and 9 V (two pads) BEC rails at 3 A each, the 9 V rail ready for a digital VTX
• ESC rated 55 A continuous and 70 A burst (10 s) per motor, BLHeli_S with DShot300/600
• 1000uF low-ESR capacitor and TVS protection diode on the ESC, with current sensing supported

Specifications

• FC MCU: STM32F405
• Gyro: ICM42688P
• Barometer: Built in
• OSD chip: AT7456E
• UARTs: 6
• Blackbox: MicroSD card slot
• BEC outputs: 5 V 3 A, 9 V 3 A
• Supported firmware: Betaflight, INAV
• Input voltage: 3-6S LiPo
• ESC current: 55 A continuous x 4, 70 A burst (10 s)
• ESC firmware: BLHeli_S J-H-40
• ESC protocol: DShot300, DShot600
• Current sensor: Supported (scale 400, offset 0)
• Mounting: 30.5 x 30.5 mm, 4 mm holes
• FC size and weight: 41.6 x 39.4 x 7.8 mm, 10.5 g
• ESC size and weight: 45.6 x 44 x 8 mm, 23.5 g

The 55 A rating leaves headroom for a 6S 5-inch build on 2207-2306 motors or a 7-inch long-range quad. Receiver, VTX and camera are not included; plan the four free UARTs around them before wiring.