Single chip low pin-count MCUs control multiple motors

October 09, 2016 // By Nick Flaherty
Toshiba Electronics Europe has developed a new range of microcontrollers that allow a single chip with a low pin count of 32 to 64 pins to control multiple motors.

The MK4 group is the second offering in Toshiba’s TXZ family of high-speed, low power consumption microcontrollers that incorporate the ARM Cortex-M core. The new MCUs meet the need to reduce energy and save space in motor control applications ranging from home appliances such as washing machines and refrigerators to power tools, ventilation fans, electric bicycles and industrial motion control.

Until now, driving two motors typically required an MCU in a 100-pin type package. Toshiba’s 64-pin TXZ family products, however, can control two motors by detecting the motor position via an integrated, high-speed analogue-to-digitai converter with a 0.5μs conversion speed.

The new devices are based on the ARM Cortex-M4F operating at up to 80MHz and incorporating a floating point processing unit. As well as the high-precision ADC, the devices feature high-speed flash memory with 80MHz operation, a co-processor for Toshiba’s original vector engine, and 3-channel op-amps with selectable gain. Together, they ensure the new products realise efficient motor control while improving the power factor and system control.

Devices in the TXZ family support the RAMScope interface, which can confirm parameters in real time without stopping motors by loading parameters relevant to motor control to RAM. A self-diagnostic function that confirms the reference voltage of the ADC, and a CRC arithmetic circuit that identifies incorrect detection for every read operation of the memory are also incorporated. This supports load mitigation of the software process required for functional safety for the IEC 60730 standard.