CAN Driver Trends and Solutions for Higher Data Rate and Energy Savings

Transcription

1 CAN Driver Trends and Solutions for Higher Data Rate and Energy Savings FTF-AUT-F0262 Dan Lenskold Product Line Manager A P R I L 0 9, TM External Use

2 Agenda CAN Market Overview and Trends Evolution of CAN ISO Standards Flexible Data and Partial Networking Impact on CAN Physical Layer External Use 1

3 CAN Physical Layer Market Dynamics Energy Efficiency Minimize standby current without impact on transceiver immunity CAN Partial Networking for energy savings new ISO standard for CAN selective wake up Functional Robustness EMC and ESD standardization Pass EMC performance criteria without common mode choke Improved safety and predictable behavior for secure communication Increased Bandwidth Reduce software download duration Increased intersystem data exchanges require higher bandwidth CAN Flexible Data to increase bandwidth with limited architecture changes Simplified Complexity Improved EMC performance to improve system cost and reliability Standard and compatible solutions OEM specifications External lab certifications External Use 2

4 CAN High Speed Market and Product Segmentation Technology developed for automotive (ISO11898) CAN Transceiver System Basis Chip ASIC CAN H Adopted in other domains Heavy vehicles - J1939 Agriculture machinery - ISO Aviation systems - Arinc 825/6 Recreational equipment Medical Factory automation EN (CANopen) EN safety-related communication (CANopen Safety) CAN PL MCU Vreg Application driver CAN PL + Vreg + Low power + Safety MCU Application driver CAN PL + Vreg + Low power + Safety + Application Driver MCU CAN L Evolution of CAN Technology: ISO (CAN Partial Networking) CAN Flexible Data CAN Market Segmentation (2015) 1.6Bu 400Mu Automotive Industrial External Use 3

5 Communication Bandwidth [ bit/s ] TM Increasing Bandwidth at Limited Cost 100M 10M 8M 1M 125K 20K 10K Flexible Data Increase bandwidth (x4, x8, x16) Low impact on Network Architecture & Cost Minimal impact on Protocol and Physical Layer LIN/J2602 time triggered Master / Slave Body, Powertrain DSI PSI5 Safety, Sensors CAN FD CAN-HS 500kbps CDMA Arbitration Differential, Immune Global Standard FlexRay time triggered TDMA Fault Tolerant Fault Tolerant, By Wire Applications Ethernet, MOST, USB, 1394-Firewire Backbones, Diagnosis Multimedia Relative Cost of Communication [ Cost/node ] External Use 4

6 ISO Standards Applicable to CAN Physical Layer MCU ECU_1 Protocol Layer TxD RxD Trx Rec XCVR CAN bus ECU_2 ECU_n Standards XCVR mode Operation ISO Transmit-Receive (Normal mode) Bi-directional interface to the physical bus ISO Low power mode and wake up Wake up on any CAN frame ISO Partial Networking, selective wake up (frame detect mode) Wake up on a dedicated frame (ISO ). Error management. CAN Flexible Data and Partial Networking Flexible data will be incorporated into the new ISO specification ISO , -5, and -6 will be merged into the ISO specification EMC/ESD target levels and limits may get tighter Additional testing will be required for Partial Networking Requires better intrinsic Physical Layer performance and functionality External Use 5

7 Conformance and ESD Test Requirements IC Manufacturing Packaging Handling/ESD HBM, MM, CDM APPLICATION ISO10605 IEC Powered and Unpowered ESD SYSTEM ISO IEC No malfunction during normal operation OEM Certification Electrical conformance ISO /5/6, and interoperability tests EMC and transient pulses ISO7637, IS , IEC62132, IEC61967 ESD IEC , ISO10605 Vehicle Integrated Circuit Electronic Control Unit External Use 6

8 Market Definition and Dynamics HS-CAN Flexible Data with Partial Networking transceivers are used in multiple automotive applications i.e. Body Electronics, ECUs, Power Train, lighting control, chassis, infotainment, diagnostics, and accessories Important Market Characteristics: Freescale has shipped over 200M CAN/LIN transceivers. CAN and LIN in our SBC products and LIN standalone transceivers Forecast of 40 Mu/yr CAN FD with Partial Networking nodes by 2020 according to Strategy Analytics GM Global B ramp begins in 2017 Functional optimization and EMC robustness are key to achieving low system cost Freescale is developing a CAN FD w/ Partial Networking product External Use 7

9 MC33901/34901 Single High Speed CAN Transceiver System cost effective and Robust Meets toughest Industrial and Automotive EMC requirements without choke Differentiating Points System Performance and Cost: Up to 1Mbit/sec systems. EMC performance without choke Efficient: Low quiescent current in low power modes (down to 8 µa) Scalable: Family of four products supporting automotive and industrial, with and without wake up Product Features Pinout and function compatible with CAN ISO and -5 standards I/O (SPI) is compatible with both 5 V and 3.3 V MCU digital levels Tx dominant timeout for automotive (MC33901) which is removed for industrial (MC34901) and low baud rate applications Low power modes and wake up capability Robustness: ESD without choke: +-8 kv ESD contact discharge according to IEC , 150 pf-330 ohms Noise Immunity without choke: Meets 36 dbm DPI without external protection and 39 dbm DPI with additional capacitors Bus pins protected against automotive transients SOIC-8 Package Automotive Timeout Industrial No Timeout Wake Up MC33901W MC34901W Typical Applications All automotive and industrial applications using CAN High Speed network Power train and safety (automotive) Motor control safety critical (industrial) Robotics (industrial) Factory automation (industrial) Standard MC33901S MC34901S External Use 8

10 MC3xCM0902 Dual CAN High Speed Transceiver System cost effective and Robust Meets toughest Industrial and Automotive EMC requirements without choke Differentiating Points System Performance and Cost : Up to 1Mbit/sec systems EMC performance without choke Efficient: Low quiescent current in low power modes (down to 15 µa) Scalable: Support for automotive and industrial markets. Complements single CAN family. Automotive: MC33CM0902 (Tx dominant timeout) Industrial: MC34CM0902 (No timeout, low baud rate applications) Product Features Pinout and function compatible with CAN ISO and -5 standards I/O (SPI) is compatible with both 5 V and 3.3 V MCU digital levels Vdd and IO voltage monitoring, ability to respond in fail-safe manner Low power modes and wake up capability Robustness: ESD without choke: +-8 kv ESD contact discharge according to IEC , 150 pf-330 ohms Noise Immunity without choke: Meets 36 dbm DPI without external protection and 39 dbm DPI with additional capacitors Bus pins protected against automotive transients SOIC-14 and DFN14eP package (forthcoming) SO14 DFN14eP Typical Applications All automotive and industrial applications using CAN High Speed network Power train and safety (automotive) Motor control safety critical (industrial) Robotics (industrial) Factory automation (industrial) External Use 9

11 Single CAN Flexible Data with Partial Networking High Speed CAN transceiver with Flexible Data and Partial Networking that will serve as the Physical Layer in all modules of the CAN network requiring selective wake-up and higher data rates Features Vbat Supply: 24 V systems: 4.5 V to 54 V (85 V Max rating) TBD OR 12 V systems: 4.5 V to 36 V (40 V MAX) ISO : sleep mode current 10 ua typical ( Wake Up Pattern detect mode) ISO : Partial Networking 500 ua max power consumption in frame detect mode Flexible Data 5 Mbps 8 Mbps (choke-less) EMC not critical 2 Mbps (choke-less): EMC certified with typical CAN criteria Low power modes Sleep 20 ua Max; standby 50 ua; frame detect 500 ua Max WAKE input: triggered by low to high OR high to low transitions INH output: VBAT-1v MIN for MCU regulator control VDD 4.5 V 5.5 V input for CAN interface SPI communications: Baud rate, WUF configuration, mode and diagnostic control SOIC-14 and DFN-14 Packages Industry standard pinout 40 to 125 C temperature range Vio Rxd Txd MOSI MISO SCLK CSB INH Bias 2.5V Level Shift Norm. & Frame Detect sleep Wake Up Pattern detector Un powered Differential receiver Pre drive r CAN Frame decoder Compare Rin Rin Sleep Receiver Wake Up Frame Clock Control /Configuration/Error counter Vbat VDD CAN H CANL GND INH LOCAL WAKE WAKE Device Block Diagram SO14 DFN14eP External Use 10

12 Flexible Data and Partial Networking Impact on CAN Physical Layer External Use 11

13 High Speed CAN Physical Layer Simplified Architecture ISO and -5 Recessive level Dominant level Vbat TxD CAN Bus 2.5V Logic 1 Logic 0 Wake up report sleep 2.5V Wake up receiver 25k +5V RxD Bit representation CAN Protocol (in MCU) Rxd Txd Un powered Differential receiver CAN H Pre CAN L driver 120//120 2us/bit (500kb/s) TxD CAN Bus RxD External Use 12

14 Signals at 500 kb/s, 2, 4 and 8 Mb/s (ISO Test Conditions: 60 ohms / 100 pf) 2us/bit (500kb/s) 500ns/bit (2Mb/s) TxD TxD CAN Bus RxD X4 CAN Bus RxD X8 500kb/s 2Mb/s 250ns/bit (4Mb/s) 125ns/bit (8Mb/s) TxD TxD CAN Bus CAN Bus RxD 4Mb/s RxD 8Mb/s External Use 13

15 New Timing Proposal Ensure a minimum duration of the recessive level, based on existing Physical Layer performances, and -2-5 testing conditions Aligned position with other silicon suppliers for 2 Mb/s External Use 14

16 ISO , Partial Networking Physical Layer Some attributes and key features: <500 ua consumption in frame detect mode, with: Bus biasing at 2.5 V Precision differential receiver, EMC immune CAN message decoding logic circuitry Precision and stable oscillator Innovation to meet timing requirement to achieve CAN frame decoding Current consumption in sleep mode Vio Rxd Txd MOSI MISO SCLK CSB ISO Standalone Physical Layer Block diagram (14 pins) with Selective Wake Up function Bias 2.5V Level Shift Norm. & Frame Detect Wake Up Pattern detector sleep Un powered Differential receiver CAN Frame decoder Compare Rin Rin Sleep Receiver Pre driver Wake Up Frame Clock Vbat VDD CAN H CANL GND Control /Configuration/Error counter INH INH LOCAL WAKE WAKE External Use 15

17 EMC Robustness External Use 16

18 EMC Test Principle (DPI) RF Power Injection Test Signals Test board RxD tolerance Failure Criteria +/-10% External Use 17

19 Direct Power Injection at 2 Mb/s Powers 45 dbm 40 Forward power Requirement level Target 45 dbm 40 Pow ers Forw ard pow er Requirement level Target #DPI12 -with CMC, Normal mode 2Mb/S (TxD 1 MHz) - Masks on RXC1 to 3 1 MHz 10 M 100 M 1 GHz CW MHz 10 M 100 M 1 GHz AM (80%, 1kHz) Maximum test level Freescale CAN IP measurement German Automotive makers limits Latest Freescale CAN HS Physical Layer MC33901 compliant with CAN Flexible Data 2M under EMI test, with external choke External Use 18

20 EMC Conducted Emission Test Principle (CE) EMI Receiver Test Board Mode Control and Test Signals TxD Spectrum External Use 19

21 dbµv dbµv kHz 150kHz 1M 1M 10M Frequency (MHz) 10M Frequency (MHz) TM 100M 100M 1GHz 1GHz EMC Conducted Emission Comparison at 500 kb/s and 2 Mb/s Chokless operation! 2us/bit (500kb/s) 500ns/bit (2Mb/s) At 500kb/s, no need for common mode choke! At higher baud rate (i.e., 2 Mb/s) Shift of noise spectrum toward higher frequencies Slight increase of the noise levels Need CMC to operate at 2 Mb/s 500ns/bit (2Mb/s) With Choke As simulated above, with bus driver optimization, level can be reduced to meet existing target External Use 20

22 Low Power and Flexible Data Overview External Use 21

23 Leakage increase Low Power Mode Consumption Technology shrink leads to smaller transistor size having lower VT threshold Low VT impact on MOSFET leakage current, due to sub threshold MOS operation When powered, and not operating, digital circuit leaks Drain current (ua) log ex 0.40nm technology Vt (0.5V) Vt (0.8V) Technology shrink ex 0.25um technology High Temp Ambiant Vgs(V) <10 ua for best in class Transceivers (without Partial Networking function) <500 ua WUP Sleep Frame detect T_silence expired (typ 1s) WUP: wake up pattern (ISO ) CAN Partial Networking Physical Layer needs to keep the ID, ID mask, WUF and baud rate configurations when transitioning from normal to sleep mode Compared to standard Physical Layer (non Partial Networking), the amount of digital circuitry supplied in sleep mode is significantly higher. Devices are designed in more advanced silicon technology 10 ua sleep current is a challenge for CAN Partial Networking Physical Layers External Use 22

24 SOF SOF ACK ACK SOF SOF CAN Flexible Data Impact on ISO Physical Layer Idle phase detection (11 recessive bits) Regular CAN Frame FD frame detection(r0 bit) => stop decoding No idle phase detection during the Fast data CAN FD Frame Fast data Flexible Data passive CAN Flexible Data frame should not disturb Partial Networking transceiver: The circuitry must be designed to avoid Error Detection and to prevent the Frame Error Counter from increasing and falsely waking up the transceiver Proper detection of End of frame / Idle detection External Use 23

25 Low Power Modes Defined in ISO Wake up report sleep Vbat 2.5V 25k Wake up receiver Only the wake up receiver active. +5V CAN Protocol (in MCU) Rxd Txd Un powered Differential receiver CAN H Pre CAN L driver 120//120 Legend Block / Function disable in Low Power mode For the typical low power modes there is no impact when using FD and Partial Networking (same ISO applies) Wake Up Frame starts with the regular baud rate Wake up filtering mechanism. Won t wake without specific WUF. External Use 24

26 Evolution and Perspective for CAN Physical Layer XCVR ECU_2 MCU Protocol Layer TxD RxD Trx Rec CAN bus ECU_n ECU_1 Standards XCVR mode Operation Perspectives ISO ISO ISO Transmit- Receive Low power mode SWU, frame detect (for Partial Networking) Interface to the physical CAN bus Wake up on any frame Wake up on a dedicated frame (ISO ). Error management. Timing optimization for FD. Flexible Data will be incorporated into the spec. Proposal for 2 Mb/s operation while meeting all EMC (Emissions and immunity) specifications. Definition/confirmation of EMC tests set up and failure criteria. No evolution on functionality. Slight increase in sleep mode current for CAN Partial Networking transceiver (digital circuitry leakage!) Flexible Data passive. Evolution to the Frame Decoding and Error Management to ensure no error is detected due to CAN Flexible Data frame. Proper End of frame detection External Use 25

27 Conflicting Technical Requirements Robustness Chokeless Bandwidth CAN Flexible Data CAN Physical Layer Emission Standards Low Power Design for LowQ External Use 26

28 MC33901 / MC34901 Ecosystem Quick performance evaluation Easy-to-use evaluation board for MC3x901 Single CAN High Speed MC33901 evaluation board KIT33901EFEVB evaluation board for CAN High Speed Physical Layer Technical support Datasheet EMC and ESD compliance reports Application notes Contact Freescale FAEs for more information External Use 27

29 Conclusion Industry trend is increased bandwidth and EMC robustness combined with energy savings CAN Network is evolving with emergence of CAN Partial Networking and CAN Flexible Data standards to support these needs, alone or combined together At Physical Layer there are conflicting challenges: Improving bandwidth, reduce immunity to power injection and increase noise emission level Reducing quiescent current, improving noise immunity, EMC, and ESD continue to be extremely important. Need to sustain performance without need for common mode choke Freescale is focusing analog innovations to support High Speed CAN, Flexible Data, and Partial Networking Contact Info: External Use 28

30 Freescale Semiconductor, Inc. External Use