Freescale TPMS Solution Introduction

Transcription

1 Freescale TPMS Solution Introduction FTF-AUT-F0481 Helen Lu AP MBD of Automotive Sensors, ASG, GSM Cindy Zhang I China FAE for Automotive Applications, GSM M A Y TM External Use

2 Agenda TPMS Market Overview Freescale TPMS Solution Status Freescale TPMS 7 x 7 mm QFN Package Introduction TPMS 7 x 7 mm QFN Package Value Proposition Design Tips Migration to the FXTH87 Family External Use 1

3 Market Overview and Freescale TPMS Status Automotive mega trends TPMS legislation around the world Freescale TPMS status External Use 2

4 SDA Sensor Data Analytics Sensing Algorithms Predictive Ease of Use SDN Software- Defined Networking Multicore Security Ease of Use ADAS Advanced Driver Assistance Systems Sensing Power Efficiency Security Ease of Use IoT Internet of Things Sensing Connectivity Power Efficiency Security Ease of Use External Use 3

5 Tire Pressure Motivated by Automotive Mega Trends Sensor Data Analytics TPMS is available for all types of vehicles including trucks and buses Scalable solutions Intelligence gained from all tires Multiple pressure ranges Multiple rotation axis Multiple RF frequencies Advanced Driver Assistance Systems Prevent roadside breakdown and risk of road congestion U.S. TREAD Act to prevent roll over accidents Future possibilities to link tire information with chassis and ADAS system Software-Defined Networking TPMS allows optimum tire inflation and thus fuel consumption and CO2 emission reduction Maximizes tire life European and Korean legislation driven by CO2 reduction Programmability and versatility Internet of Things Provides accurate tire data to the driver Filling assistant app on smart phones Fleets & Trucks: enables better tire management Smart and secure hardware and software solutions External Use 4

6 TPMS Legislation Around the World Region USA European Union South Korea / Japan Requirements Regulation from 2005: FMVSS138 mandates TPMS for new vehicles starting in October 2005 Regulation from 2012: EC mandates TPMS starting Nov 2012 for new type approved vehicles and for all new vehicles starting in November 2014 Regulation from 2013: TPMS vehicles to be installed on passenger cars from January 2013 for new models and January 2015 for existing models China Recommended specification Enforcement standard in drafting stage. Draft will be done and submitted to the National Standard Committee by end of May Taiwan Standard published in Nov 2012 and to be implemented starting November 2014 Russia, Kazakhstan, Belarus (Eurasia) Indonesia, Israel, Malaysia, Philippines, Turkey Valid from 2015 onwards and replaces national legislation Require European whole vehicle type approval for vehicles imported from Europe. As a consequence TPMS will be required for all new vehicles in November External Use 5

7 TPMS Potential Market Size Ramp up from million new cars sold per year by the end of the decade 4 wheels per car + spare tires For car OEMs China car production about 15M# per year *4 = 60M# TPMS sensors 1 billion cars on the road worldwide today! Great aftermarket opportunity Module Replacement (Battery run out) Great potential for tire mounted solutions Heavy trucks, buses, motorcycles, all vehicles with tires Market outside of transportation requiring battery operated wireless pressure sensing External Use 6

8 Freescale TPMS Status Freescale has qualified its generation 3.0 integrated tire pressure monitoring device MPXY85xx and MPXY86xx Production delivery to customers since 2011 (supporting multiple large customers) Qualification on going of the new TPMS in 7 x 7 mm QFN package TPMS in 7 x 7 mm QFN package recommended for new designs External Use 7

9 TPMS FXTH87 Family Introducing the world s smallest TPMS on the market External Use 8

10 FXTH87 Family Tire Pressure Monitoring System Microcontroller S08 core, 0.25 um SGF technology 16 kb SGF flash (8 kb firmware, 8 kb customer), 512B RAM, 64 parameter registers 10-bit ADC, temperature sensor and thermal restart 1-channel LF detector and decoder 8 MHz clock, 2-ch timer, 1 khz LFO Integrated RF transmitter Frac-N PLL based transmitter, 315/434 MHz FSK/ASK modulation Manchester or bi-phase encoding -1 dbm to +8 dbm output power Design Considerations: RF Tx (7 5 dbm) LF Rx (4 ua, snif) Process Technology 0.25 um Core Type S08 Voltage Supplies 1.8 V to 3.6 V (transmit) Voltage Supplies 2.3 V to 3.6 V (measure) Packaging Requirements Media protection Pressure Sensor CMOS capacitive p-cell w/o signal conditioning Acceleration Sensor Z-axis or dual XZ Package FAM 7 x 7 mm QFN External Use 9

11 FXTH87 Family Benefits Smallest TPMS sensor on the market QFN 7 x 7 x 2.2 mm package Multiple pressure sensor ranges 450, 900 and 1500 kpa Dual axis accelerometer for extended sensing functionalities Embedded MCU and dedicated firmware Large memory space for customer application LF and RF wireless interface Ultra low power consumption (for battery or battery less applications) External Use 10

12 TPMS Product Family 40% smaller than previous generation! MPXY85xx MPXY86xx FXTH87xx0 FXTH87xx1 QFN 9 x 9 mm Limited prod capacity Single Z-axis 450 kpa and 900 kpa pressure ranges QFN 9 x 9 m m Limited prod capacity Dual XZ-axis 450 kpa and 900 kpa pressure ranges QFN 7 x 7 mm High prod capacity More robust package Single Z-axis Improved LF SO8 microcontroller with SO8 microcontroller with 450 kpa and 900 kpa 8 kb customer flash 8 kb customer flash pressure ranges Internal 315/434 MHz RF Internal 315/434 MHz RF SO8 microcontroller transmitter transmitter with 8 kb customer flash Internal 315/434 MHz RF transmitter QFN 7 x 7 mm High prod capacity More robust package Dual XZ-axis Improved LF 450 kpa and 900 kpa pressure ranges SO8 microcontroller with 8 kb customer flash Internal 315/434 MHz RF transmitter Automotive External Use 11

13 Competitive Positioning and Value Proposition Customers cost benefit Smaller in size: 7 mm x 7 mm x 2.2 mm Saving on board size, potting and housing materials Saving on module weight (car OEM requirement) Boot loader design allows uploading software through LF Dual-axis accelerometer provides improved angular detection resolution capability Longer battery life RF transmitting power consumption <7 ma at 5 dbm Universal interoperability for aftermarket opportunities Flash 8k space, 512 bytes RAM for customers Freescale customer memory space and dual-axis accelerometer enable the development of the largest module portfolio suitable for more car models (inventory/operation/ production management benefit) External Use 12

14 Status TPMS 7 x 7 mm Production and Software Schedule (*) Milestones 450 or 900 kpa Z or XZ version 1500 kpa XZ version Samples (EV) Now Early October 2014 PPAP End June 2014 End December 2014 Volume Production End June 2014 Dual Axis Accelerometer Angular Position Detection Flexible Flash Library (10 kb user space) End Nov 2014 End Aug 2014 End March 2015 (after safe launch plan) LF Based Flash Boot Loader End Dec 2014 (*) = All dates here-above could change without any further notice. Please consult Freescale Sales Representative for schedule update. External Use 13

15 Design Tips RF Design LF Design Firmware Sensor Routines External Use 14

16 FXTH87 Family Tire Pressure Monitor Sensor X ACCEL The FXTH87 family has the following features: 8-bit MCU S08 Core with SIM, interrupt and debug/monitor 512 Bytes RAM 16 K Flash (8 K for Freescale library available, 8 K for applications) 64-byte, low power, parameter registers Calibrated /compensated temperature, pressure, voltage sensors Pressure options: 450, 900, or 1500 kpa ranges Accelerometer options: Z-axis or dual XZ-axis 10-bit analog-to-digital converter (ADC10) Dedicated state machines to sequence routine measurement and transmission processes for reduced power consumption Internal 315/434 MHz RF transmitter ASK and FSK modulation capability Programmable data rate generator Manchester, Bi-Phase or NRZ data encoding 256-bit RF data buffer variable length interrupt Differential input LF detector/decoder 6 Multi-purpose GPIO pins Real time interrupt driven by LFO with interrupt intervals of 8, 16, 32, 64, 128, 256, 512 or 1024 msec Low power wake-up timer and periodic reset driven by LFO Watchdog time-out with selectable times and clock sources 2-channel general purpose timer/pwm module (TPM1) Internal oscillators Low voltage detection External Use 15

17 Tire Pressure Monitoring System Application Diagram External Use 16

18 RF Basics The transmitter generates a radio frequency (RF) signal OOK : The signal is canceled during low level FSK : The frequency of the wave varies with the value of the modulating signal The transmitter matching network optimize the transfer of power until the antenna The transmitter antenna transforms this RF signal to an electromagnetic wave The wave propagates to the receiver s antenna The receiver antenna collects the wave at RF frequency The receiver matching network optimizes the transfer of power until the receiver input The receiver processes the signal Transmitter Transmit Matching Network Either OOK modulation Or FSK modulation Receive Matching Network Receiver External Use 17

19 Impedance Locations to be Presented at the RF Pin 315 MHz Impedance => 88 + j*171 Parallel equivalent => 420 Ohm // 109 nh (resonating with 2.34 pf) (Impedance at PA plane, real part only as inductive part at RF pin resonates with internal capacitive component) (package + bonding + Pad..) 434 MHz Impedance => 51 + j*137 Parallel equivalent => 415 Ohm // 57 nh (resonating with 2.35 pf) External Use 18

20 Software Sample program in CodeWarrior: RF Frame format below: Preamble Volt Temp Press X-axis Z-axis CRC8 Postamble External Use 19

21 LF Receiver Carrier Mode Amplitude frequency duration Data Mode Carrier Mode + Datagram in Manchester format Direct Mode Data Mode with no Manchester decoding Used in rare cases External Use 20

22 LF Manchester Datagram A 4 msec of CW Preamble Two data s transition to allow a clean demodulation establishment 9 t DATA synchronization 16 bits of Wake-up bytes (x5e and x31) 4 bytes of data s (x13,xc6,x6c,x3a) One End of Message frame (illegal Manchester bit at a databyte boundary) External Use 21

23 Q-factor Recommendation The combination of the external LF antenna and any external components as shown in Figure 12-6 should not significantly filter the envelope of the LF carrier as shown in Figure Excessive filtering will cause the received message error rate (MER) to increase. External Use 22

24 TPMS MCU Power Modes Variable RUN STOP4 STOP1 Active clocks HFO, MFO, LFO MFO, LFO RAM (512 bytes) Active Stand-by Off PARAM (64 bytes) LFO Active Active Active RF Transmitter Optionally On Optionally On Optionally On LF Receiver Optionally On Optionally On Optionally On Sensors Optionally On Optionally On Off MCU On and clocking Stand-by, not clocking PWU ON ON ON GPIOs ON Levels maintained Off Hi-Z Interrupts Optionally ON Optionally ON Some On, Some off, will start code from main() External Use 23

25 Firmware Sensor Routines Voltage-encoded signal ADC Digital Measurement Compensation Compensated Measurement Freescale Firmware Library TPMS_READ routines TPMS_COMP routines Analog World Digital World TPMS_READ routines help acquire raw sensor data TPMS_COMP routines linearize raw sensor input External Use 24

26 Data Flow for Compensated Measurements (1/3) Voltage-encoded Battery Voltage TPMS_READ_ VOLTAGE 10-BIT Raw Voltage TPMS_COMP_ VOLTAGE 8-BIT Compensated Voltage Voltage-encoded Temperature TPMS_READ_ TEMP 12-BIT Raw Temperature TPMS_COMP_ TEMP 8-BIT Compensated Temperature In this context, compensated means linearized over its own scale External Use 25

27 Data Flow for Compensated Measurements (2/3) Voltage-encoded Pressure TPMS_READ_ PRESSURE 10-BIT Raw Pressure 10-BIT Raw Voltage TPMS_COMP_ PRESSURE 9-BIT Compensated Pressure 12-BIT Raw Temperature In this context, compensated means linearized over voltage, temperature, and its own scale External Use 26

28 Data Flow for Compensated Measurements (3/3) Voltage-encoded Acceleration TPMS_READ_ ACCEL 10-BIT Raw Accel 10-BIT Raw Voltage TPMS_COMP_ ACCEL 9-BIT Compensated Pressure 12-BIT Raw Temperature In this context, compensated means linearized over voltage, temperature, and its own scale External Use 27

29 Power-Saving Strategies Periodically call TPMS_READ_* routines, but only call TPMS_COMP_* routines if raw values have shifted significantly or if a long period of time has elapsed When calling TPMS_COMP_PRESSURE or TPMS_COMP_ACCELERATION, reutilize existing voltage and temperature data instead of requesting new data External Use 28

30 Z or X-axis (counts) TPMS_READ_ACCEL Functionality Threshold Moving Park Mode Time (s) TPMS_READ_ACCEL and TPMS_COMP_ACCEL are useful when trying to determine whether a vehicle is moving or is stopped Choose a threshold to determine if the car is moving, i.e., if X or Z below threshold, car is stopped and above threshold car is moving External Use 29

31 Zraw (counts) TPMS_READ_ACCEL Functionality Time (s) TPMS_READ_ACCEL can also be used to determine position in the tire i.e., each local maximum indicates top-most position in the tire, each local minimum indicates bottom-most position in the tire External Use 30

32 How to measure +/-1g during high speed tire rotation? Use the TPMS_READ_DYNAMIC_ACCEL function Dynamic Ranges Full Accelerometer Range Freescale Tire Pressure Monitoring Sensors provide the ability to measure -210 up to 300 g by use of sixteen 60 g offsets, each with a resolution of 0.12 g per count Ranges overlap by around 250 counts Range 5 Range 6 Range 7 External Use 31

33 How to measure +/-1 g during high speed tire rotation? (2/2) The TPMS_READ_DYNAMIC_ACCEL function: Will sweep through ranges until it finds a useful one Will return acceleration for the given range Digital output is offset by the range index E.g., a reading of 256 at range index step 6 is 0 g. The same reading with index step 7 is 30 g. External Use 32

34 Migration of the MPXY85XX/86XX to the FXTH87 Family Schematic design PCB layout Limited software change External Use 33

35 Migration Cross Reference Freescale TPMS QFN 9x9 Part Number Freescale TPMS QFN 7x7 Part Number P-cell Range (kpa) Axis of Acceleration Z-range Standard Z-Offset Accuracy X-range Standard X-Offset Accuracy MPXY8510DK016T1 or MPXV8510DK016T1 FXTH870502DT Z MPXY8610DK6T1 FXTH870511DT XZ MPXY8500DK016T1 or FXTH870902DT Z MPXV8500DK016T1 MPXY8600DK6T1 FXTH870911DT XZ -270g /+ 350g range with 40g sensitivity -210g/+240g range with 60g sensitivity -270g /+ 350g range with 40g sensitivity -210g/+240g range with 60g sensitivity +/- 6g +/- 5g +/- 6g +/- 5g -70g/+80g range with 10g sensitivity -70g/+80g range with 10g sensitivity +/- 4g +/- 4g FXTH870912DT XZ -270g /+ 350g range with 40g sensitivity +/- 6g -70g/+80g range with 10g sensitivity +/- 4g External Use 34

36 Designing with Freescale Tailored live, hands-on training in a city near you 2014 seminar topics include QorIQ product family update Kinetis K, L, E, V series MCU product training freescale.com/dwf External Use 35

37 Freescale Semiconductor, Inc. External Use