Silabs公司的C8051F85x/86x系列產品是全集成的混合信號系統級(SoC)MCU,集成了上電重置,電壓監視器,看門狗定時器和時鐘振蕩器,高達8kB閃存,片上調試,12位ADC等,工作電壓2.2V-3.6V,可以用在馬達控制.本文介紹了C8051F85x/86x系列主要特性,框圖,以及BLDC馬達參考設計動力板和MCU板主要特性,框圖,電路圖以及材料清單.

The C8051F85x/86x device family are fully integrated, mixed-signal system-on-a-chip MCUs. With on-chip power-on reset, voltage supply monitor, watchdog timer, and clock oscillator, the C8051F85x/86x devices are truly standalone system-on-a-chip solutions. The flash memory is reprogrammable in-circuit, providing non-volatile data storage and allowing field upgrades of the firmware. The on-chip debugging interface (C2) allows non-intrusive (uses no on-chip resources), full speed, in-circuit debugging using the production MCU installed in the final application. This debug logic supports inspection and modification of memory and registers, setting breakpoints, single stepping, and run and halt commands. All analog and digital peripherals are fully functional while debugging. Each device is specified for 2.2 to 3.6 V operation, and are available in 20-pin QFN, 16-pin SOIC or 24-pin QSOP packages. All package options are lead-free and RoHS compliant. The device is available in two temperature grades: -40to +85 ℃ or –40to +125 ℃.

C8051F85x/86x主要特性:



圖1.C8051F85x/86x系列方框圖

C8051F850 BLDC馬達參考設計套件

This design kit provides a complete system-level solution for sensorless, brushless dc (BLDC) motors. This application note includes complete schematics, PCB layouts and firmware.

This kit supports 3-phase BLDC motors that meet the following specifications:

Trapezoidal back-EMF
Max operating voltage of between 10 V to 24 V dc
24 kHz PWM frequency
Maximum average current of 10 A
Maximum speed not exceeding 200,000 rpm for a 2-pole BLDC motor
Overcurrent detection capability stops the motor when average current exceeds 10 A.
Motor Stall detect capability stops the motor when a motor stall is detected or extreme loads encountered.
Tachometer Frequency Generator (FG) output signal

The kit aims to demonstrate the capabilities of the C8051F850 for operating BLDC motors. The unique features offered by this MCU for BLDC motor operation are:

PWM synchronized blanking of comparator for BEMF Zero-Crossing Detection
Automatic PWM duty cycle reduction to limit motor current during startup
Hyperdrive mode to increase the maximum speed of some motors

C8051F850 BLDC馬達參考設計套件包括:

One MCU Board: MCRD-MCU-C8051F850 with the motor control firmware preprogrammed into the MCU
One Powertrain Board: MCRD-PWR-NLV-F85X
One BLDC Motor: Turnigy 450 Series 3800 kV Brushless Outrunner Helicopter Motor
One Motor Mount Board
One 8-bit MCU Kit CD
One 12 V, 5 Amp Universal Input Power Adapter

圖2.C8051F850 BLDC馬達參考設計框圖

1.動力板
The powertrain board is designed to meet the following key motor specifications:
Motor supply voltage range of 10 to 24 V
Maximum average current of 10 amps
It consists of the following components that are relevant to this application:
6 IRFH7446 Power MOSFETS for the inverter circuit
3 Silicon Labs Si8230 isolated dual drivers
An LDO to generate the 3.3 V required by the MCU board
50 m current sensing resistor rated for 10 W
Motor terminal blocks to allow user to attach their own motor
Resistor divider to generate attenuated motor voltage supply (VMDC) - allows MCU to determine if motor supply voltage is high enough for safe operation
Resistor dividers to generate attenuated motor phase voltages with a small positive offset voltage (VMA,VMB, VMC)
Resistor network to generate attenuated sum of motor phase voltages with a small positive offset voltage(VMY)
2.MCU板
The MCU board consists of the following:
C8051F850-A-GU QSOP-24 package
2 push-buttons
3 controllable LEDs
1 rotary variable resistance potentiometer
Op-amp to amplify and bias the current sense voltage
USB Hub to support:
C2 USB debug interface
CP2103 USB-UART bridge operating at 115200 baud
CP2112 USB-I2C bridge
Configurable jumpers to select either Hall-sensored or sensorless mode of operation
Test points for connecting to gate drive of user powertrain board and motor.

圖3.C8051F850 BLDC馬達參考設計外形圖

圖4.C8051F850 BLDC馬達參考設計電路圖:動力板(1)

圖5.C8051F850 BLDC馬達參考設計電路圖:動力板(2)

圖6.C8051F850 BLDC馬達參考設計電路圖:動力板(3)

圖7.C8051F850 BLDC馬達參考設計電路圖:MCU板

圖8.C8051F850 BLDC馬達參考設計電路圖:運放

圖9.C8051F850 BLDC馬達參考設計電路圖:USB橋

圖10.C8051F850 BLDC馬達參考設計電路圖:USB Hub

圖11.C8051F850 BLDC馬達參考設計電路圖:連接器

圖12.C8051F850 BLDC馬達參考設計電路圖:低成本BLDC馬達設計樣板
C8051F850 BLDC馬達參考設計動力板材料清單:



C8051F850 BLDC馬達參考設計MCU板材料清單: