BLHeli_S is an improved version of the base BLHeli code.
BLHeli_S delivers a throttle response that is Smooth as Silk, and the main factor contributing to this, is that it uses hardware to generate motor PWM. Two MCUs support this for BLHeli_S, namely the BusyBee1 at 24MHz (EFM8BB10F8) and the BusyBee2 at 48MHz (EFM8BB21F16).
BLHeli_S will have the same good Sync holding properties as base BLHeli. Maybe even better.
BLHeli_S generally does Startup better than base BLHeli.
BLHeli_S does damped light. Only.
BLHeli_S has motor PWM that is Synchronous to the MCU master clock, as it is generated by hardware. This makes the motor Silent.
BLHeli_S has very Small throttle Steps. The resolution varies between hardware configurations (MCU clock speed and driver type), and is between a nominal 512 steps and 2048 steps.
BLHeli_S supports very high motor Speeds. A BB1 MCU will support 350k erpm, and the limit of the BB2 is not yet known, so the code is set to limit at 500k erpm.
BLHeli_S supports regular 1-2ms input signal, as well as Oneshot125, Oneshot42 and Multishot. Autodetected when the ESC sees an input signal.
1:input Voltage:2-4S Lipo
2: NO BEC
3:Continue Current:20A,Burst Current:25A up to 10S
5:Weight:4g(include Power and signal wire)
6:Support Damped mode,Oneshot125,Oneshot42 and Multishot
7:Main IC:SILABS EFM8BB21F16 ,MCU run 48MHz
8:MOS:Both low and high side fets are Nfets
9:Switching speed is very fast,it has dedicated driver chip
10:BLHeli S Bootloader & Firmware