OnSemiNCV7381单路FlexRay总线驱动解决方案
2013-07-24
On Semi 公司的NCV7381是单路FlexRay总线驱动器,和FlexRay电物理层指标Rev.3.0.1兼容,通信速度高达10Mbps,在有线的FlexRay通信中提供差分通信媒界,具有极好的EMC和ESD性能,工作温度−40°C 到+125°C,符合汽车级质量标准.本文介绍了NCV7381主要特性,框图和应用框图,FlexRay总线驱动器应用电路图以及NCV7381 APP V2评估板主要特性,框图,电路图,元件清单和PCB布局图.
NCV7381 is a single−channel FlexRay bus driver compliant with the FlexRay Electrical Physical Layer Specification Rev. 3.0.1, capable of communicating at speeds of up to 10 Mbit/s. It provides differential transmit and receive capability between a wired FlexRay communication medium on one side and a protocol controller and a host on the other side. NCV7381 mode control functionality is optimized for nodes permanently connected to car battery.
It offers excellent EMC and ESD performance.
NCV7381主要特性:
General
• Compliant with FlexRay Electrical Physical Layer Specification Rev 3.0.1
• FlexRay Transmitter and Receiver in Normal−power Modes for Communication up to 10 Mbit/s
• Support of 60 ns Bit Time
• FlexRay Low−power Mode Receiver for Remote Wakeup Detection
• Excellent Electromagnetic Susceptibility (EMS) Level over Full Frequency Range. Very Low Electromagnetic Emissions (EME)
• Bus Pins Protected against >10 kV System ESD Pulses
• Safe Behavior under Missing Supply or No Supply Conditions
• Interface Pins for a Protocol Controller and a Host (TxD, RxD, TxEN, RxEN, STBN, BGE, EN, ERRN)
• INH Output for Control of External Regulators
• Local Wakeup Pin WAKE
• TxEN Time−out
• BGE Feedback
• Supply Pins VBAT, VCC, VIO with Independent Voltage Ramp Up:
♦ VBAT Supply Parametrical Range from 5.5 V to 50 V
♦ VCC Supply Parametrical Range from 4.75 V to 5.25 V
♦ VIO Supply Parametrical Range from 2.3 V to 5.25 V
• Compatible with 14 V and 28 V Systems
• Operating Ambient Temperature −40°C to +125°C (TAMB_Class1)
• Junction Temperature Monitoring with Two Levels
• SSOP−16 Package
FlexRay Functional Classes
• Bus Driver Voltage Regulator Control
• Bus Driver – Bus Guardian Interface
• Bus Driver Logic Level Adaptation
• Bus Driver Remote Wakeup Quality
• Automotive Qualification According to AEC−Q100 (Rev. F)
图1.NCV7381框图
图2.NCV7381应用框图
图3.NCV7381 FlexRay总线驱动器应用电路图
NCV7381 APP V2评估板
This document describes the NCV7381 APP V2 Evaluation board for the ON Semiconductor NCV7381 FlexRay Bus Driver. The functionality and major parameters can be evaluated with the NCV7381_APP_v2 board.
The NCV7381 is a single-channel FlexRay bus driver compliant with the FlexRay Electrical Physical Layer Specification Rev. 3.0.1, capable of communicating at speeds of up to 10 Mb/s. It provides differential transmit and receive capability between a wired FlexRay communication medium on one side and a protocol controller and a host on the other side.
NCV7381 mode control functionality is optimized for nodes permanently connected to car battery.
The NCV7381_APP_V2 Evaluation board is a reference design for stand-alone 2-channel FlexRay node. The board is intended to give designers easy, quick and convenient means for evaluation of NCV7381 FlexRay bus drivers. The design incorporates complete node solution with possibility of modifications and small board size. A set of two boards allows users immediately start with the NCV7381 FlexRay Bus Driver. The MCU is preprogrammed with a firmware which provides simple mode control and FlexRay communication. With use of Freescale[1] BDM programmer and a suitable development environment, the MCU firmware can be freely modified and reprogrammed.
图4.NCV7381 APP V2评估板外形图
Board Hardware
The board consists of MCU with integrated 2-channel FlexRay communication controller interconnected with two separate FlexRay bus drivers (NCV7381), two switchable voltage regulators and peripherals. The board is prepared for various modifications in power supply concept and FlexRay bus termination, and allows simple extension of the system by unused MCU pins. USB interface provides compatibility with standard PC. The address of each board can be easily modified by address switch what allows creating complex FlexRay network without need of reprogramming the MCU.
Implemented High Speed CAN interface can be used as a diagnostic interface in a network built from several nodes. For evaluation purposes NCV7381 is populated with several LED diodes and most of the bus driver signals are comfortable accessible to oscilloscope probes.
NCV73812037EVB评估板主要特性:
FlexRay Transceiver
Two Separate FlexRay Channels with NCV7381 Bus Driver Compliant with the FlexRay Electrical Physical Layer Specification Rev. 3.0.1
Reconfigurable Bus Termination – End Node/Middle Node
Common Mode Choke and Additional ESD Protection Footprint
SUBD-9 Connectors – FlexRay bus
Local Wakeup Switch
MCU
Freescale[1] 16-bit MC9S12XF Family MCU
Integrated FlexRay Communication Controller (Protocol Specification Rev. 2.1)
Integrated CAN 2.0 A, B Controller
Background Debug Modul – Single-wire Communication with Host Development System
512 kB Flash
32 kB RAM
50 MHz Maximum CPU Bus Frequency
Relatively Small 112-pin LQFP Package
Peripherals
Optical Isolated USB Interface (USB to UART Converter)
Additional CAN Interface
All NCV7381 Digital I/O Pins Connected to Test Points – Easy Connection to Logic Analyzer
8 General Purpose LEDs
Address Switch
Other
Two Automotive Voltage Regulators with Inhibit Function (Input Battery Voltage Up to 42 V)
Power Supplies Voltage Monitoring
Instant 2-nodes FlexRay Network with Running Communication by Connecting Two NCV7381 EVBs
PC Configuration Software under Development (Available upon Request)PCB Layout
The FlexRay Transceiver, the ESD Protection and the Common Mode Choke are Placed near to the FlexRay the ECU
Connector
The FlexRay Signal Lines (BP, BM) are Decoupled from Disturbances on the ECU Board
The Routing of the FlexRay Lines (BP, BM, TX and TXEN) is Symmetric
The Distance between the Lines BP and BM resp. TX and TXEN is Minimized
图5.NCV7381 APP V2评估板框图
图6.NCV7381 APP V2评估板电路图
NCV7381 APP V2评估板材料清单(BOM):
图7.NCV7381 APP V2评估板主要元件分布图
图标:
1 Power Supply Input Connector 9 FlexRay BD Signals Test Points (Channel A)
2 Aux Digital I/O Connector 10 FlexRay BD Signals Test Points (Channel B)
3 CAN Backbone Connector 1 11 MCU Reset Switch
4 CAN Backbone Connector 2 12 MCU External Interrupt Switch
5 USB Interface 13 BD Local Wakeup Switch (Channel A)
6 Address Switch 14 BD Local Wakeup Switch (Channel B)
7 FlexRay CC Strobe Output Signals 15 FlexRay Bus Connector (Channel A)
8 BDM Connector (MCU Debugging Interface) 16 FlexRay Bus Connector (Channel B)
9 FlexRay BD Signals Test Points (Channel A)
10 FlexRay BD Signals Test Points (Channel B)
11 MCU Reset Switch
12 MCU External Interrupt Switch
13 BD Local Wakeup Switch (Channel A)
14 BD Local Wakeup Switch (Channel B)
15 FlexRay Bus Connector (Channel A)
16 FlexRay Bus Connector (Channel B)
图8.NCV7381 APP V2评估板元件布局图(顶层)
图9.NCV7381 APP V2评估板元件布局图(底层)
图10.NCV7381 APP V2评估板PCB布局图(顶层)
图11.NCV7381 APP V2评估板PCB布局图(底层)
详情请见:
http://www.onsemi.cn/pub_link/Collateral/NCV7381-D.PDF
和
http://www.onsemi.cn/pub_link/Collateral/EVBUM2037-D.PDF
以及
http://www.onsemi.cn/pub_link/Collateral/NCV73810V2GEVB_SCHEMATIC.PDF