Introducing BlueCore2-External, the second generation Bluetooth solution Cambridge Silicon Radio Unit 300 , Science Park,Milton Road Cambridge, CB4 0XL, United Kingdom Tel: +44 1223 424167 www.csr.com
The Future of the End-User Market For Bluetooth Devices • The market for Bluetooth devices will expand rapidly in the next few years • Bluetooth will become an important selling feature in a huge variety of products • Customers will increasingly demand more than just basic Bluetooth features, adding: • Security • Interoperability • Performance • Product development cycles will be compressed bringing the need to reuse technology from previous product generations as much as possible • Prices for end user devices will be forced down • The life cycle of new devices will get shorter
What Kind Of Characteristics Will Be Needed For Success? • Short Time To Market: for maximum market responsiveness • Fully Featured Bluetooth implementation: to get the maximum end-user value from Bluetooth • Low cost base: to be profitable in a competitive market • A focus on value added features: To differentiate customer end products
How Can BlueCore2-External Help? • Time To Market: • Easy to pass qualification tests • Can be supplied with compatible Host Software • Full RF designs and application support provided • Bluetooth Features • The most functional base-band in the industry • Industry leading protocol firmware • Full support for ACL, SCO, USB, Piconet, Scatternet and DFU • Unique Security features • Low Cost • CMOS technology • Minimum external components: for class 2 operation Bluecore2-External requires just a single Balum, no LNA, and no TX/RX switch.
How Can BlueCore2-External Help? • All this leaves you to focus on what is really important : creating attractive, fully featured end-user products:
BlueCore2-External: Features • BlueCore2-External is the latest Bluetooth solution from CSR • Single chip: radio and microcontoller are located on the same die • Industry standard CMOS silicon (0.18mm process) • 32kbytes of internal RAM • Support for up to 8Mbits of external Flash • Interfaces: PCM, USB, UART, I2C • 0.5mm or 0.65mm ball pitch (6´6mm or 8´8mm package) • 96 Ball VFBGA package
Focus On Time To Market • How can the new BlueCore2-External device reduce time to market? • Design: BlueCore2-External comes with full RF designs (including PCB layouts and detailed BOM) • Radio performance is excellent across the full industrial temperature range so it is easy to produce a device which passes all the Bluetooth qualification tests with ease • Host Software: CSR can supply host software suitable for PC or embedded platforms. This is pre-configured to work correctly with BlueCore2-External. Qualified
BlueCore2-External - A CMOS RF engine that excels • Bluetooth Qualification test: Sensitivity: RCA/CA/02/C RCA/CA/02/C Output Power: TRM/CA/01/C • Blue Lines - levels needed to pass Qualification Tests • Outcome: BlueCore2 External operates within Bluetooth limits between -35 and 110°C • Circuit: CSR standard test circuit (details available)
Adjacent Channel Power • Bluetooth Qualification Test: “TX Output Spectrum -adjacent channel power” TRM/CA/06/C • Outcome - PASS • Transmit Power = 7dBm • Temperature=20°C Circuit: CSR standard test circuit (details available) (1) Maximum allowed adjacent channel power (f=f0 + 2MHz). (2) Maximum allowed adjacent channel power (f=f0 + 3MHz).
20dB Bandwidth • Bluetooth Qualification Test: “TX Output Spectrum - 20dB bandwidth” TRM/CA/05/C; • Outcome - PASS • Transmit Power = 7dBm • Measurement bandwidth= 10kHz • Temperature=20°C Circuit: CSR standard test circuit (details available) (1) Maximum allowed 20dB bandwidth.
Transmitter Eye Diagram • Optimum eye with limited Inter-Symbol Interferance • Transmit Power = 7dBm • Data: full DH5 packet including preamble (approx. 2500 bits) • Temperature= 20°C • Circuit: CSR standard test circuit (details available)
Drift Test • Bluetooth Qualification Test: “Carrier Frequency Drift” TRM/CA/09/C • Red lines are the bounds for a test pass • Outcome: PASS • Transmit Power = 7dBm • Temperature=20°C • Circuit: CSR standard test circuit (details available)
Synthesiser Settling • BlueCore2 settles very quickly - before the output power is fully ramped up. • Bluetooth Qualification Tests: “Carrier Frequency Drift” TRM/CA/09/C ”Initial Carrier Frequency Tolerance” TRM/CA/09/C • Outcome: Pass • Transmit Power = 7dBm • Temperature=20°C • Circuit: CSR standard test circuit (details available)
Minimum Modulation Test • Bluetooth Qualification Test: TRA/CA/07/C “Modulation Characteristics” • Green lines are the bounds for a test pass • Outcome: PASS • Transmit Power = 7dBm • Temperature=20°C • Circuit: CSR standard test circuit (details available)
Maximum Modulation Test • Bluetooth Qualification Test: TRA/CA/07/C “Modulation Characteristics” • Average modulation must be between 140 and 175KHz. • BlueCore2-External average modulation = 165kHz • Outcome: PASS • Transmit Power = 7dBm • Temperature=20°C • Circuit: CSR standard test circuit (details available)
All RF Designs Included • Including: • Schematic • PCB Layout • Detailed BOM • Comprehensive application support
Host Software - Reducing Complexity • Bluecore2-External can be supplied with host side software: • Suitable for Windows 98SE, Windows ME, Windows 2000 • Standard Windows interface for ease of use • Can be OEM Branded • No additional software engineering necessary • BlueCore2 - the industry’s only truly complete Bluetooth solution
Prototyping With BlueCore2-External • Bluecore2-External is the first is the BlueCore2 family. • BlueCore2-External - the BlueCore2 radio andbase-band IC used with external Flash memory device for flexibility and low cost • BlueCore2-Flash - the BlueCore2 radio and base-band together with integrated 8Mbit flash memory for small size and high flexibility • BlueCore2-ROM - BlueCore2 with firmware on integrated 4MbitROM for small size and lowest cost • BlueCore2-External can be used to develop software for the other devices: • External Flash can be reprogrammed very quickly • When software is ready customers can switch toBlueCore2-ROM for the smallest possible solution
Focus On Bluetooth Features • The first generation of Bluetooth products offer only basic point to point connections • Consumers will soon expect much more: • Security • Data Integrity • Multi-point features • Power Saving • Real world performance, e.g. interoperability and performance in noisy environments • Only vendors who supply these feature will prosper in the future highly competitive Market for Bluetooth devices
Security • Security is important to prevent: • eavesdropping: with obvious implications • unauthorised access to networks: system managers can no longer rely on physical security • fraudulent use of other people’s cell ‘phones • malicious attacks
Security • Although these appear obvious, there are subtleties within Bluetooth which must be understood if a system is to be secure: • Not all devices have an input mechanism (computer mice, headsets etc). Therefore fixed PINs must be supported (and in fact are mandatory for several profiles), and must be stored securely • If a device can be cloned, then access is immediately open to any device it is paired with. So things like Bluetooth address and all keys must not be easily changed by the user once the module is made: without this feature someone can use your ‘phone and you’d never catch them! • Encryption must still work with power saving modes • The basis of the Bluetooth security is random numbers. These must be true random numbers, not pseudo random • Although DFU is highly desirable to allow upgrade, if not authenticated then a virus could render all Bluetooth devices unusable or even just destroy the security (for instance send the link keys to an email account!) • Some devices require firmware to be downloaded from the host into device RAM at boot time. As well as having a large die size to accommodate all the RAM such devices are extremely vulnerable to attack from malicious code masquerading as legitimate firmware.
Security • To solve these issues CSR has taken great care, and offers the following unique and comprehensive features: • Full Bluetooth authentication and encryption, with the maximum length settable at module manufacture up to 128 bits • Broadcast encryption during Park mode • Fixed PINs in the LM • Two level access to the non volatile storage, with a security bit set at the end of manufacture • Link keys can optionally be stored in the SIM card of a cell phone rather than in the Bluetooth module • A proprietary (patent applied for) true random number generator. The sequence is different each time even after chip resets, and can never be predicted • Digital signature based on 1024 bit RSA for firmware upgrades. Each module manufacturer chooses his private and public keys independently, so no unauthorised firmware can be loaded by DFU
Data Integrity • L2CAP is supposed to be reliable through error recovery at baseband • Actually baseband error recovery is not 100% reliable, so it is impossible to completely escape the effects of • Interference • Extremes of range • The probability of corruption of L2CAP data under these conditions is shown in the following graphs:
Data Integrity - the probability of errors as a function of packet type As can be seen, a naïve selection of packet type will result in corruption at L2CAP. But some profiles (eg printer) assume that L2CAP is reliable - the Baseband must therefore make a good choice of packet type.
Data Integrity - the effect of bit error rate on bandwidth Although one might at first think that the maximum data rate will always be achieved with long DH packets, it can be seen that this is not the case due to the re-try probability. A good algorithm selects a packet type that simultaneously gives maximum data rate and best integrity
Channel Quality Driven Data Rate Dynamic RF Power Control = Channel Quality Driven Data Rate = Can you talk louder? Can you talk more slowly?
Data Integrity, conclusions • An algorithm that selects packet type solely on the amount data to be sent will cause data corruption • There is a mechanism built in to Bluetooth, Channel Quality Driven Data Rate (CQDDR), which solves range or constant interference issues if correctly implemented • Solutions without CQDDR will not be able to maintain high bandwidth connections in noisy, real world environments and will cause some profiles simply not to work • CQDDR is likely to become a mandatory part of the Bluetooth 1.1 spec in future • The connection manager or application (in the upper layer stack) can make intelligent tradeoffs between bandwidth and integrity, but only if it has access to packet and BER statistics. CSR provides these via bccmd (note this is made use of today in some more sophisticated applications) • Additional recovery from burst errors (due to interference) can be built into the baseband: this is an area where there are strong differences between implementations
Data Integrity - questions to ask a potential silicon supplier • What is the maximum data rate achievable using your device? • What is the aggregate data rate when transferring bi-directional data? • What is the aggregate data rate when transferring bi-directional data between multiple slaves? • How do these degrade in the presence of other piconets? • What is the guaranteed reliability at L2CAP with your system? What happens at range extremes? • Does your solution support Channel Quality Driven Data Rate? • Note: the ability of the upper stack to recover from L2CAP errors does have some relevance
Audio Features • BlueCore2-External has flexible A PCM interface which interfaces directly to devices such as: • Qualcomm MSM 3000/5000, (CDMA device with codec interface), • OKI MSM7705, (four channel µ/A-law codec), • Motorola MC145481, (8-bit µ/A-law codec), • Motorola MC145483, (13-bit linear codec), • Mitel MT93LI6 (Echo canceller). • This makes BlueCore2-External ideal for audio applications such as: • Cordless Telephone Base-stations • Audio Gateway Applications • Conference Calling Equipment
Multi-User features • Multi-User applications for Bluetooth look set to become very popular: • Shared printers for offices, airliners, trains etc • Network access points • Telephony systems
Multi-User features, Continued • Which Bluetooth features are necessary in order to serve these application? • Role Switching, from master to slave and vice versa • Ability to be discovered and connected to while already master of a piconet (I.e. a limited Scatternet) • Simultaneous data and voice • Received Signal Strength Indication and Power Control • Load balancing • Call hand off
Multi-User features, continued • Consider a network access point: • Role Switching, from master to slave and vice versa • Vital, to allow connection to be initiated by either the access point or the client computer • Limited Scatternet • Needed when initiating connection to a device which is already acting as a master • Allows device to be both a slave and a master • Usually necessary until role switch possible • This is much more important than being slave in two piconets • Received Signal Strength Indication and Power Control • needed to support load balancing • needed for call hand off, which allows roaming
Power Saving Modes • The Bluetooth spec includes power saving modes • Park mode • Sniff mode • Hold mode • These are are essential for low power operation • Battery life will be a key differentiator between Bluetooth enabled end-user products • Sniff mode is essential for small battery powered peripherals like headsets, human interface devices while connected • Park mode is mandatory for many profiles
Power Saving Modes • Even devices without power constraints need to be able to support battery powered devices. • For example consider a mains powered, Bluetooth enabled PC: • A Bluetooth enabled Mouse or Keyboard needs to go into power saving mode, • This is only possible if the PC also supports Sniff • Thus a PC, an audio gateway or an access point must support Park and Sniff or they can’t be used with wireless mice, keyboards headsets or cell ‘phone handsets! • Bluetooth allows the low power device to use an inaccurate clock. Unless the Baseband design can accept and generate LMP Timing Accuracy Request and accept the specified 250ppm, then it is not Bluetooth compliant. We believe that many implementations are deficient in this regard.
Battery Life • Assuming that the Bluetooth silicon supports power saving modes, what other factors influence battery life? • Power Consumption usually stated as follows: • Current consumption during transmit • Current consumption during receive • Current consumption when idle or Parked • But the end user is concerned only with Battery Life, so in practice how does power consumption relate to battery life?
Battery life - duty cycle • Need to consider whole duty cycle: • PDA user: • Download web page (receive power consumption) - 10 seconds • Read web page (either parked or in Sniff mode, latency ~1 to 2 seconds) - 120 seconds • Voice link (SCO channel HV3 packets) • Transmit approx. 15% of duty cycle • Receive approx. 15% of duty cycle • Idle approx. 70% of duty cycle • It is misleading to compare current consumption figures of radio only; often power consumption when connected but not transferring data has the most impact on battery life • The highly integrated system approach of CSR gives the lowest energy consumption in battery powered applications when one considers real usage
Power Saving Modes • CSR BlueCore2-External power consumption in different modes.
Features Round-up Publicly Declared features that are Bluetooth Qualified: Limited Encryption Allows ‘eavesdroppers’ in some situations Only CSR Most don’t do Park yet! (very important for majority of embedded, battery powered applications) Essential for Access Points Some do not qualify basic functions yet e.g. Voice Many are not reliable at high temperature Only CSR supports secure firmware upgrade via standard DFU interface. Others may be impossible to upgrade or vulnerable to virus attack Data gathered from Bluetooth Qualification website, 3rd October 2001
CSR - The Business Case • The Business Case for BlueCore2-External is clear: • Excellent performance specification in all areas RF, Baseband functions, firmware • Complete solutions with host resident software also offered • Unparalleled security of supply by use of CMOS processing • Low cost by use of CMOS processing • A verifiable roadmap for future cost reductions ($5 and beyond) based on the rapid development path of CMOS processing • A commitment to Bluetooth
Reliable Supply Is Essential • If an end-user walks into a shop to purchase your product they expect it to be immediately available. If it is not you risk: • Lost sales • Lost market share • Customer dissatisfaction • Lack of credibility Canall silicon suppliers offer security of supply?
CMOS - Can You Risk Using Anything Else? BlueCore2-External, like all CSR products, uses industry standard, advanced CMOS technology • CSR’s foundry partners are the top volume producers of CMOS • ST Microelectronics - the third largest independent semiconductor company in the world • TSMC - the largest wafer foundry supplier in the world CMOS BICMOS SiGe SOI Number of fabs > 50 11 5 < 5 Mask levels 25 - 28 32 - 39 32 - 36 > 30 Relative Cost / mm2 100% 150% 180% >150%
Availability - questions to ask a potential silicon supplier • How many alternative fab’s are there capable of making your device? • What contingency plans do you have in place? • Is your manufacturing capability scalable? • Could you supply 100 Million devices?
A Believable Roadmap to $5 and Beyond • When talking about cost two elements need to be considered: • The cost of the Bluetooth device • The cost of all the external components
A Believable Roadmap to $5 and Beyond • The cost of a device depends on many factors including: • Die Size • Cost of manufacturing • BlueCore2-External: • Smallest die - the CSR stack delivers full speed data transfer, mixed voice and data, plus seven slave piconet using less than 32Kbyte RAM. Others need up to 256K. • Standard CMOS technology - for low cost manufacturing
Halve Your Component Costs With Combined Tx/Rx Terminals • BlueCore2-External has unique internally switched transmit and receive terminals. • This reduces the number of external components needed. Not needed (class 2): • One Balum = $0.44 • RF Switch = $0.46 • Saving = $0.90/chip • This circuit configuration has been used for CSR’s qualification tests at 85°C Competition Device BlueCore2-External
Cost - questions for potential silicon suppliers • How many separate chips does your solution require? • Extra chips mean extra cost • What is the total number of interconnects? • Multiple chip solutions often require extremely complex PCB design • How many external components (crystals etc)? • For class2 operation BlueCore2-external requires only a single balun and no LNA • What is the danger of shortages of the external components? • BlueCore2-External requires only standard components, available from multiple sources • Do you have a realistic roadmap to a $5 solution? • Only a single chip CMOS part will deliver the year-on-year price reduction demanded by the industry
Summary • BlueCore2-External will: • Shorten Your Time to Market • Allow you to Achieve maximum end-user value from Bluetooth • Reduce the overall cost of your Bluetooth implementation