Three-phase brushless motor controller ICs have sine wave drive
Two three-phase brushless motor controller ICs from Toshiba Electronics Europe are based on InPAC, Toshiba’s original automatic phase adjustment function. This eliminates the need for phase adjustment, explains the company, and achieves high levels of efficiency at a wide range of motor rotation speeds.
The TC78B041FNG and TC78B042FTG controllers can be used with motor drivers that have various voltages and current capacities and can be used in combination with intelligent power devices at the output stages.
The TC78B041FNG and TC78B042FTG are intended for use in home appliances such as air-conditioners and air purifiers, and industrial equipment where inverters are increasingly being used to control fan motors, to improve energy efficiency and lower audible noise.
To obtain high-level efficiency in conventional systems, it is necessary to adjust the phase of the motor voltage and motor current for individual fan motors. Realising high efficiency over a wide range of rotational speeds — from almost zero rotations per minute (RPM) at start-up to high speeds of several thousand RPM — requires a large component count for phase adjustment. It also introduces the need for a complex microcontroller control system, which is time-consuming to develop.
InPAC control technology automatically adjusts the phase of the Hall signal and motor current to drive motors with an efficiency equivalent to that of a microcontroller control system, over a wide range of rotation speeds. InPAC delivers a high efficiency fan motor system with sine wave drive that reduces audible noise, adds Toshiba.
As the phase adjustment is performed automatically via simple settings, the lengthy development time for software and microcontroller adjustment is eliminated.
The TC78B041FNG and TC78B042FTG controllers include a forward/reverse detection switch and motor lock detection. The number of pulses in the rotation pulse signal is selectable.
The TC78B041FNG is housed in a 7.6 x 10.2 x 1.6mm SSOP30 package and includes an error detection positive input. The TC78B042FTG is in a 5.0 x 5.0 x 1.0mm VQFN32 package and includes error detection on the positive and negative inputs.
Both devices are in mass production now.