Afro30 30A ESC

From Hobbyking's website specifications:

Current Draw: 30A Continuous
Voltage Range: 2-4s Lipoly
BEC: 0.5A Linear
Input Freq: 1KHz
Firmware: afro_nfet.hex
Discharge wire/plugs: 16AWG/Male 3.5mm
Motor wire/plugs: 15AWG/Female 3.5mm
Weight: 26.5g (Included wire, plug, heat shrink)
Size: 50 x 25 x 11mm
Fig 1:

Fig 1 shows a Afro30 30A ESC.

The ESC has no BEMF filter capacitors, and all N FETs. It does have a red (sync error) and green (armed) LED that are useful for diagnostic purposes.

The appropriate SimonK module is afro_nfet.hex.

The ESC comes with bootloader installed, but I have written the latest bootloader and set the lock bits as the current version of the bootloader seems reliable. Future flash and EEPROM updates done via the servo connector using a Turnigy USB Linker.


The ESC contains a linear BEC rated at 0.5A in the manufacturers specifications. It uses independent regulators for the BEC and MCU.

BEC tests were conducted with no motor load.

An LM2940L in SOT-223 package is used for the BEC, rather smaller than used on most competitive ESCs. Though rated at 4S. 0.5A at 25° ambient sends the BEC into thermal shutdown, it does withstand 0.5A on 3S (package temp rise 80°), in fact it withstood 0.70A at 25° ambient.

Though smaller than most competitive ESCs, four of these on a multi-rotor should happily supply up to 2A total with cooling from the propeller draft, more than sufficient for most simple applications (FC + rx).


The Afro30 0A ESC is a sound basic N FET ESC with integral BEC, and two diagnostic LEDs.

The ESC uses common Atmega8 TQFP32 hardware, is supplied with SimonK firmware and is readily flashed with third party firmware.

No warranty

Advice (or a warning) to those who might try to replace the firmware on an ESC. Most FW comes with no warranty, and typically the OEM firmware is read protected so you cannot save and restore it. In most cases, changing the firmware may terminate any seller's warranty.

In making hardware or firmware modifications, you may damage the ESC, or the model may fail and cause consequential damage.

The author gives no warranty and makes no representations about the suitability of this technique or any particular products for the end user, or the accuracy of the article content, they must inform themselves and make their own judgment aware that there are risks. If you are not competent to do these things, don't do them!


The article should not be seen as a recommendation or endorsement of any products.

The products shown in this article are from Hobbyking who manufacture products under a range of brand names, possibly creating an illusion of competition. Their products tend to be low in cost and low in quality, products are not good value when you have to throw a proportion of them in the rubbish because the cost of returning them exceeds the value of the replacement which is only available after excessive delay, many follow ups and haggling. If you see the claim [o]ther stores will force you to ship the product back to China in full retail packaging every time! Hobbyking's warranty service is professional, fair and fast, don't believe it, it doesn't work that way in my experience... I get better service from most eBay sellers!




Version Date Description
1.01 16/08/2013 Initial.

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