External Use

TM

CAN Driver Trends and Solutions for

Higher Data Rate and Energy Savings

FTF-AUT-F0262

A P R I L 0 9 , 2 0 1 4

Dan Lenskold | Product Line Manager

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External Use 1

Agenda

• CAN Market Overview and Trends

• Evolution of CAN ISO Standards

• Flexible Data and Partial Networking Impact on CAN

Physical Layer

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External Use 2

CAN Physical Layer Market Dynamics

Increased Bandwidth

Functional Robustness

Simplified Complexity

• Reduce software download duration

• Increased intersystem data

exchanges require higher bandwidth

• CAN Flexible Data to increase

bandwidth with limited architecture

changes

• Improved EMC performance to

improve system cost and reliability

• Standard and compatible

solutions – OEM specifications

• External lab certifications

• EMC and ESD standardization

• Pass EMC performance criteria

without common mode choke

• Improved safety and predictable

behavior for secure communication

Energy Efficiency

• Minimize standby current without

impact on transceiver immunity

• CAN Partial Networking for energy

savings – new ISO standard 11898-

6 for CAN selective wake up

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External Use 3

CAN High Speed Market and Product Segmentation

System

Basis Chip

ASIC

CAN H

CAN L

CAN

Transceiver

CAN

PL

MCU

Vreg

Application

driver

CAN PL + Vreg

+ Low power

+ Safety

MCU

Application

driver

CAN PL + Vreg

+ Low power

+ Safety

+ Application

Driver

MCU

Technology developed for

automotive (ISO11898)

Adopted in other domains Heavy vehicles - J1939

Agriculture machinery - ISO 11783

Aviation systems - Arinc 825/6

Recreational equipment

Medical

Factory automation EN 50325-4 (CANopen)

EN 50325-5 safety-related

communication (CANopen Safety)

Evolution of CAN Technology: ISO11898-6 (CAN Partial

Networking)

CAN Flexible Data

1.6Bu

400Mu

CAN Market Segmentation (2015)

Automotive

Industrial

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External Use 4

DSI – PSI5

100M

20K

10M

1M

125K

Co

mm

un

icati

on

Ban

dw

idth

[

bit

/s ]

Relative Cost of Communication [ Cost/node ] 0.5 1 2.5 5

Backbones, Diagnosis

Multimedia

Increasing Bandwidth at Limited Cost

10K

8M CAN FD

CAN-HS 500kbps

CDMA Arbitration

Differential, Immune

FlexRay time triggered TDMA Fault Tolerant

Ethernet,

MOST, USB,

1394-Firewire

LIN/J2602 time triggered Master / Slave

Fault Tolerant,

By Wire Applications

Safety, Sensors

Global Standard

Body, Powertrain

Flexible Data

• Increase bandwidth (x4, x8, x16)

• Low impact on Network Architecture & Cost

• Minimal impact on Protocol and Physical Layer

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External Use 5

ISO Standards Applicable to CAN Physical Layer

• CAN Flexible Data and Partial Networking − Flexible data will be incorporated into the new ISO11898-1 specification

− ISO11898 -2, -5, and -6 will be merged into the ISO11898-2 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

Standards XCVR mode Operation

ISO11898-2 Transmit-Receive (Normal mode) Bi-directional interface to the physical bus

ISO11898-5 Low power mode and wake up Wake up on any CAN frame

ISO11898-6 Partial Networking, selective wake

up (frame detect mode)

Wake up on a dedicated frame (ISO11898-1).

Error management.

MCU

Protocol

Layer

Trx

Rec

TxD

RxD

XCVR

ECU_1

CAN bus

ECU_n

ECU_2

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External Use 6

Conformance and ESD Test Requirements

Vehicle

Electronic Control Unit

Integrated Circuit

Manufacturing

Packaging

Handling/ESD

HBM, MM, CDM

ISO10605

IEC61000-4-2

Powered and

Unpowered ESD

ISO10605 - IEC61000-4-2

No malfunction during

normal operation

APPLICATION IC SYSTEM

OEM Certification Electrical conformance

ISO 11898-2/5/6, and “interoperability” tests

EMC and transient pulses ISO7637, IS011452-4, IEC62132, IEC61967

ESD IEC61000-4-2, ISO10605

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External Use 7

Market Definition and Dynamics

• 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

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

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External Use 8

MC33901/34901 Single High Speed CAN Transceiver System cost effective and Robust

Meets toughest Industrial and Automotive EMC

requirements… without choke

Automotive

Timeout

Industrial

No Timeout

Wake Up MC33901W MC34901W

Standard MC33901S MC34901S

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 ISO11898-2 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 IEC61000-4-2, 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

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)

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External Use 9

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 ISO11898-2 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 IEC61000-4-2, 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)

MC3xCM0902 Dual CAN High Speed Transceiver System cost effective and Robust

Meets toughest Industrial and Automotive EMC

requirements… without choke

DFN14eP SO14

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)

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External Use 10

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

DFN14eP SO14

Vbat

MOSI

MISO

SCLK

CSB

VDD

CAN H

CANL

Txd

Rxd Differential

receiver

sleep

Un powered

CAN

Frame

decoder

Wake Up

Frame

Compare

Clock

Control /Configuration/Error counter

Bias

2.5V

Vio

GND Level

Shift

INH LOCAL WAKE WAKE INH

Rin

Wake

Up

Pattern

detector

Norm. & Frame Detect Rin

Sleep

Receiver

Pre

drive

r

Device Block Diagram

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)

• ISO11898-5: sleep mode current 10 uA typical (“Wake Up Pattern” detect mode)

• ISO11898-6: 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

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External Use 11

Flexible Data and Partial Networking Impact

on CAN Physical Layer

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External Use 12

High Speed CAN Physical Layer

Simplified Architecture – ISO11898-2 and -5

TxD

CAN Bus

RxD

Bit representation

Logic “1” Logic “0”

2.5V

Dominant

level

Recessive

level

+5V

Pre

driver 120//120

2.5V

25k

CAN H

CAN L Txd

Rxd Differential

receiver

sleep

Wake up

receiver

Vbat

Un powered

CAN

Protocol

(in MCU)

Wake up

report

2us/bit (500kb/s)

TxD

RxD

CAN

Bus

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External Use 13

Signals at 500 kb/s, 2, 4 and 8 Mb/s

(ISO11898-2 Test Conditions: 60 ohms / 100 pF)

2us/bit (500kb/s)

500kb/s

TxD

RxD

CAN

Bus

500ns/bit (2Mb/s)

X4

2Mb/s

TxD

RxD

CAN

Bus

125ns/bit (8Mb/s)

8Mb/s

TxD

RxD

CAN

Bus

250ns/bit (4Mb/s)

X8

4Mb/s

TxD

RxD

CAN

Bus

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External Use 14

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

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External Use 15

ISO11898-6, Partial Networking Physical Layer

ISO11898-6 Standalone Physical

Layer Block diagram (14 pins)

with Selective Wake Up function

Vbat

MOSI

MISO

SCLK

CSB

VDD

CAN H

CANL

Txd

Rxd Differential

receiver

sleep

Un powered

CAN Frame

decoder

Wake Up Frame

Compare

Clock

Control /Configuration/Error counter

Bias

2.5V

Vio

GND Level

Shift

INH LOCAL WAKE WAKE INH

Rin

Wake Up

Pattern

detector

Norm. & Frame Detect Rin

Sleep

Receiver

Pre

driver

• 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

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External Use 16

EMC Robustness

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External Use 17

EMC Test Principle (DPI)

RxD tolerance

RF Power Injection

Test board

Test Signals

Failure Criteria

+/-10%

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External Use 18

Direct Power Injection at 2 Mb/s

Forward power

Requirement level

Target

45

dBm

0

40

35

30

25

20

15

10

5

CW

1 GHz 1 MHz 10 M 100 M

Powers

Forw ard pow er

Requirement level

Target

45

dBm

0

40

35

30

25

20

15

10

5

AM (80%, 1kHz)

1 GHz1 MHz 10 M 100 M

Pow ers

•#DPI12 -with CMC, Normal mode

2Mb/S (TxD 1 MHz) - Masks on RXC1 to 3

German Automotive makers’ limits

Freescale CAN IP measurement

Maximum test level

Latest Freescale CAN HS Physical Layer

MC33901 compliant with CAN Flexible

Data 2M under EMI test, with external

choke

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External Use 19

EMC Conducted Emission Test Principle (CE)

EMI Receiver

Test Board

Mode Control

and

Test Signals

TxD

Spectrum

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External Use 20

EMC Conducted Emission Comparison at 500 kb/s

and 2 Mb/s

500ns/bit (2Mb/s)

With Choke

150kHz 1GHz10M1M 100M

Frequency (MHz)

-20

80

dBµV

0

60

30

0

50

20

-10

70

40

10

2us/bit (500kb/s)

150kHz 1GHz10M1M 100M

Frequency (MHz)

-20

80

dBµV

0

60

30

0

50

20

-10

70

40

10

500ns/bit (2Mb/s)

Chokless

operation !

• 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

− As simulated above, with bus driver optimization, level can be reduced to meet existing target

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External Use 21

Low Power and Flexible Data

Overview

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External Use 22

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”

Sleep

Frame

detect

WUP

T_silence

expired

(typ 1s)

<500 uA

<10 uA for best in

class Transceivers

(without Partial

Networking function)

WUP: wake up pattern (ISO11898-6)

Drain current

(uA) log

Vgs(V)

ex 0.25um technology

ex 0.40nm technology

Vt (0.5V)

High Temp

Ambiant

Technology shrink

Leakage in

cre

ase

Vt (0.8V)

• 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

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External Use 23

CAN Flexible Data Impact on ISO11898-6 Physical Layer

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”

Regular CAN Frame

Idle phase detection (11 recessive bits)

No idle phase detection during the Fast data

CAN FD Frame

FD frame detection(r0 bit)

=> stop decoding

SO

F

SO

F

AC

K

AC

K

Fast data

SO

F

SO

F

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External Use 24

Low Power Modes Defined in ISO11898-5

+5V

Pre

driver 120//120

2.5V 25k

CAN H

CAN L Txd

Rxd Differential

receiver

sleep

Wake up

report

Wake up

receiver

Un powered

Vbat

Only the wake up

receiver active.

CAN

Protocol

(in MCU)

Block / Function disable in

Low ¨Power mode

Legend

For the typical low power modes there is no impact when using

FD and Partial Networking (same ISO11898-5 applies)

Wake Up Frame starts with the “regular” baud rate

Wake up filtering mechanism. Won’t wake without specific WUF.

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External Use 25

Evolution and Perspective for CAN Physical Layer

MCU

Protocol

Layer

Trx

Rec

TxD

RxD

XCVR

ECU_1

CAN bus

ECU_n

ECU_2

Standards XCVR mode Operation Perspectives

ISO11898-2 Transmit-

Receive

Interface to the

physical CAN bus

Timing optimization for FD. Flexible Data will be

incorporated into the 11898-2 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.

ISO11898-5 Low power

mode

Wake up on any

frame

No evolution on functionality.

Slight increase in sleep mode current for CAN

Partial Networking transceiver (digital circuitry

leakage!)

ISO11898-6

SWU, frame

detect (for

Partial

Networking)

Wake up on a

dedicated frame

(ISO11898-1).

Error management.

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

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External Use 26

CAN

Physical Layer

Robustness

Chokeless

Emission

Standards

Low Power

Design for LowQ

Bandwidth

CAN Flexible

Data

Conflicting Technical Requirements

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External Use 27

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

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External Use 28

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:

− Dan.Lenskold@freescale.com

TM

© 2014 Freescale Semiconductor, Inc. | External Use

www.Freescale.com