原标题：ADI ADSP-CM408F混合信号控制处理器评估方案

　　ADI公的ADSP-CM40x系列是基于ARM® Cortex-M4内核的混合信号控制处理器,具有浮点运算单元,工作频率高达240MHz,并集成了高达384KB SRAM,2MB闪存,加速器和外设备以及包括两个16位SAR型ADC和两个12位DAC的模拟模块,最适合用在马达控制和光伏(PV)逆变器控制.本文介绍了ADSP-CM40x系列主要特性和框图,内核Cortex-M4框图以及ADSP-CM408F EZ-KIT Lite®评估系统主要特性,框图,电路图和材料清单, PCB元件布局图.

　　The ADSP-CM40x family of mixed-signal control processors is based on the ARM® Cortex-M4TM processor core with floating point unit operating at frequencies up to 240 MHz and integrating up to 384KB of SRAM memory, 2MB of flash memory, accelerators and peripherals optimized for motor control and photo-voltaic (PV) inverter control and an analog module consisting of two 16-bit SAR-type ADCs and two 12-bit DACs. The ADSP-CM40x family operates from a single voltage supply (VDD_EXT/VDD_ANA), generating its own internal voltage supplies using internal voltage regulators and an external pass transistor.

　　This family of mixed-signal control processors offers low static power consumption and is produced with a low-power and low voltage design methodology, delivering world class processor and ADC performance with lower power consumption.

　　By integrating a rich set of industry-leading system peripherals and memory, the ADSP-CM40x mixed-signal control processors are the platform of choice for next-generation applications that require RISC programmability, advanced communications and leading-edge signal processing in one integrated package. These applications span a wide array of markets including power/motor control, embedded industrial, instrumentation, medical and consumer.

　　Each ADSP-CM40x family member contains the following modules.

　　• 8 GP timers with PWM output

　　• 3-Phase PWM units with up to 4 output pairs per unit

　　• 2 CAN modules

　　• 1 two-wire interface (TWI) module

　　• 3 UARTs

　　ADSP-CM40x系列主要特性:

　　100 MHz to 240 MHz ARM Cortex-M4 with floating-point unit

　　128K Byte to 384K Byte zero-wait-state L1 SRAM with

　　16K Byte L1 cache

　　Up to 2M Byte flash memory

　　16-bit asynchronous external memory interface

　　Enhanced PWM units

　　Four 3rd/4th order SINC filters for glueless connection of isolated ADCs

　　Harmonic analysis engine

　　10/100 Ethernet MAC

　　Full Speed USB On-the-Go (OTG)

　　Two CAN (controller area network) 2.0B interfaces

　　Three UART ports

　　Two Serial Peripheral Interface (SPI-compatible) ports

　　Eight 32-bit general-purpose timers

　　Four Encoder Interfaces, 2 with frequency division

　　Single power supply

　　176-lead (24 mm × 24 mm) RoHS compliant LQFP package

　　120-lead (14 mm × 14 mm) RoHS compliant LQFP package

　　ANALOG SUBSYSTEM FEATURES

　　ADC controller (ADCC) and DAC controller (DACC)

　　Two 16-bit SAR ADCs with up to 24 multiplexed inputs,

　　supporting dual simultaneous conversion in 380 ns (16-bit,

　　no missing codes, ±3.5LSB INL)

　　Two 12-bit R-string DACs, with output rate up to 50 kHz

　　Two 2.5 V precision voltage reference outputs

　　ARM CORTEX-M4 CORE

　　The ARM Cortex-M4, is a 32-bit reduced instruction set computer (RISC). It uses a single 32-bit bus for instruction and data. The length of the data can be eight bits, 16 bits, or 32 bits. The length of the instruction word is 16 or 32 bits. The controller has the following features.

　　Cortex-M4 Architecture

　　• Thumb-2 ISA Technology

　　• DSP and SIMD extensions

　　• Single cycle MAC (Up to 32 × 32 + 64 -> 64)

　　• Hardware Divide Instructions

　　• Single-precision FPU

　　• NVIC Interrupt Controller (129 Interrupts and 16 Priorities)

　　• Memory Protection Unit (MPU)

　　• Full CoreSightTM Debug, Trace, Breakpoints, Watchpoints, and Cross-Triggers

　　图1. ADSP-CM40x系列内核Cortex-M4框图

　　图2. ADSP-CM40x系列框图

　　ADSP-CM408F EZ-KIT Lite®评估系统

　　This EZ-KIT Lite is designed to demonstrate the ADSP-CM408F processor’s capabilities. The ADSP-CM408F EZ-KIT Lite has a 30 MHz input clock and runs at 240 MHZ internally.

　　USB circuitry and a mini USB AB connector are provided for connecting to the EZ-KIT Lite as a host or a device. The frequency for the USB circuit is generated internally to the processor.

　　User I/O to the processor is provided in the form of two user push buttons and four LEDs. The software-controlled switches (SoftConfig) facilitate the switch multi-functionality by disconnecting the push buttons from their associated processor pins and reusing the pins elsewhere on the board.

　　The ADSP-CM408F processor is based on the ARM® Cortex®-M4 processor core and is designed for motor control and industrial applications.

　　The EZ-KIT Lite is shipped with all of the necessary hardware—you can start the evaluation immediately. The package contains the standalone evaluation board, CE-approved power supply, and USB cable. The EZ-KIT Lite version ships with the J-Link Lite ARM, while the EZ-Board® version requires the customer to provide an emulator.

　　Two expansion connectors (analog interface and PWM/digital interface) are provided for connecting boards that incorporate motors. Another expansion connector is provided for connecting an Anybus board and/or a memory/FPGA extender card.

　　Traditional mechanical switches for changing the board’s factory setup have been removed in favor of I2C controlled software switches. The only remaining mechanical switches are the boot mode switch and push buttons.

　　The evaluation board is designed to be used in conjunction with the IAR Embedded Workbench development tools to test capabilities of the ADSP-CM408F processors. The development environment aids advanced application code development and debug, such as:

　　• Create, compile, assemble, and link application programs written in C++, C, and assembly

　　• Load, run, step, halt, and set breakpoints in application programs

　　• Read and write data and program memory

　　• Read and write core and peripheral registers

　　图3. ADSP-CM408F EZ-KIT Lite®评估板外形图

　　ADSP-CM408F EZ-KIT Lite®评估板主要特性:

　　• Analog Devices ADSP-CM408F processor

　　• 176-pin LQFP package

　　• 30 MHz CLKIN core oscillator

　　• SRAM memory (SMC0) chip

　　• 256K x 16-bit (4M bit)

　　• Cypress CY7C1041DV33

　　• Ethernet PHY (ETH0)

　　• 10/100 Mb/s

　　• Texas Instruments DP83848C

　　• Universal Asynchronous Receiver/Transmitter (UART0)

　　• Analog Devices ADM3252E RS-232 line transceiver

　　• DB9 female connector

　　• Universal Asynchronous Receiver/Transmitter (UART1)

　　• Analog Devices ADM2682E RS-485 line transceiver

　　• DB9 female connector

　　• Controller Area Network (CAN) interfaces

　　• CAN0—Analog Devices ADM3053 transceiver and RJ11 connector

　　• CAN1—Analog Devices ADM3053 transceiver and RJ11 connector

　　• USB interface

　　• Molex 56579-0576 connector

　　• Display

　　• New Haven NHD-0220D3Z-FL-GBW

　　• 2 x 20 character

　　• 2-wire interface (TWI) control

　　• RESET controller

　　• Analog Devices ADM708 microprocessor supervisory circuits

　　• Debug (JTAG/SWD/SWV/TRACE) interface

　　• JTAG/SWD 20-pin 0.1” header for use with IAR emulators

　　• Trace/JTAG/SWD/SWV 20-pin 0.05” header

　　• LEDs

　　• Eight LEDs: one power (green), one board reset (red), one Ethernet speed (green), one SYS_FAULT (red), and four general-purpose (amber)

　　• Push buttons

　　• Four push buttons: one reset, one wake, two IRQ/Flag

　　• Asynchronous connector

　　• 180-pin Samtec (QSH-090-01-F-D-A) 0.5 mm spacing

　　• SMC0 address, data, and control

　　• CLKOUT

　　• SPI1

　　• UART2

　　• TWI0

　　• GPIOs

　　• RESET

　　• GND/3.3V/5V output

　　• Pulse-width modulation (PWM) connector

　　• 180-pin Samtec (QSH-090-01-F-D-A) 0.5 mm spacing

　　• PWM0—PWM2

　　• SINC0

　　• SPI1

　　• SPT0

　　• TWI0

　　• TMR0

　　• CNT0—CNT3

　　• GPIO

　　• RESET

　　• GND/3.3V/5V output

　　• 5V output

　　• Analog connector interface

　　• 120-pin Samtec (QSH-060-01-F-D-A) 0.5 mm spacing

　　• ADC0

　　• AGND/GND/VREF/5VOUT

　　• ADR441 voltage reference (VREF)

　　• ADA4899 buffer—0.1” header for reference

　　• 1588 connector

　　• 0.1” header 6-pin

　　• External power supply

　　• CE compliant

　　• 5V @ 3.6 Amps

　　• Ability to power from the PWM connector

　　• Other features

　　• 0.05-ohm resistors for processor current measurement

　　图4. ADSP-CM408F EZ-KIT Lite®评估板框图

　　ADSP-CM408F EZ-KIT Lite®评估板材料清单(BOM):