Reference Design For Automotive Motor Management

The reference design for automotive motor management combines microcontroller know-how and interfaces to boost effectivity and cut back house.

The S32M276SFFRD is a reference design from NXP Semiconductors tailor-made for automotive BLDC and PMSM motor management purposes. It makes use of the S32M276 built-in system, which mixes a 32-bit Arm Cortex-M7 S32K3 microcontroller and an analogue element that features a voltage regulator, gate driver, and present sensor inside a single system-in-package (SiP) design.

The reference design board goals to scale back each the invoice of supplies (BOM) and PCB dimensions. It incorporates a compact measurement of lower than 2 inches in diameter (5 cm) and effectively handles BLDC/PMSM motor management purposes. Moreover, the design has numerous interfaces, together with UART and CAN with an inside PHY, RGB LED, a JTAG 10-pin connector, faston connectors for energy provide, and a 3-phase motor connection.

The design operates with an exterior voltage provide of +12V/5A. An inside analogue extension handles the S32M276’s energy administration die throughout the SiP, which distributes the mandatory inside energy using the desired 12V provide. This integration not solely minimizes the invoice of supplies but in addition conserves house.

The design options JTAG connectors for MCU programming through a PE Multilink Common FX Debug Probe. This probe permits customers to regulate the goal’s execution, entry and modify registers and reminiscence values, debug code on the processor, and program inside and exterior FLASH reminiscence gadgets. It facilitates serial and debug communications between a USB host and an embedded goal processor.

The microcontroller integrates a Digital Programmable Achieve Amplifier (DPGA) for low-side present measurements. This element incorporates a digital programmable present sense amplifier with adjustable inside achieve settings, a blanking time counter, and an over-current comparator, which measures the voltage drop throughout the present sense resistor. 

The GDU options three gate driver cases, every able to driving one high-side FET and one low-side FET. These drivers are important for working the three phases of a brushless DC motor. The first perform of every driver is to toggle a MOSFET between its on and off states. The pre-driver boosts management indicators to the mandatory ranges to actuate the ability MOSFET. For dependable efficiency, the low-side drivers are powered by the VLS regulator, whereas the bootstrap circuit straight provides the high-side drivers.

Regardless of the board’s compact measurement, this reference design features a BLDC motor encoder connector to boost motor management precision. Sometimes, BLDC motors include solely three encoder indicators along with the ability pins. Nevertheless, this design provides an additional pin to the connector. Relying on the shopper’s software wants, this LED can point out standing or be used for code testing.

NXP has examined this reference design. It comes with a invoice of supplies (BOM), schematics, meeting drawing, printed circuit board (PCB) structure, and extra. The corporate’s web site has further knowledge concerning the reference design. To learn extra about this reference design, click on right here.