LICAL-ENC-MS001

HIGH-PERFORMANCE MS SERIES ENCODER WIRELESS MADE SIMPLE ® MS SERIES ENCODER DATA GUIDE DESCRIPTION MS Series encoders and decoders are designed for remote control applications. They allow the status of up to eight buttons or contacts to be securely transferred via a wireless link. The large, twenty-four bit address size makes transmissions highly unique, minimizing the possibility of multiple devices having conflicting addresses. The MS Series decoder allows the recognition of individual output lines to be easily defined for each transmitter by the manufacturer or the user. This enables the creation of unique user groups and relationships. The decoder also identifies and outputs the originating encoder ID for logging or identification. Housed in a tiny 20-pin SSOP package, MS Series encoders feature low supply voltage and current consumption. Selectable baud rates and latched or momentary outputs make the MS Series truly versatile. 0.309 (7.85) 0.026 (0.65) 0.207 (5.25) C Ro HS OMP IAN T L LICAL-ENC-MS001 YYWWNNN 0.013 (0.32) 0.284 (7.20) 0.007 (0.18) 0.030 (0.75) Figure 1: Package Dimensions FEATURES Secure possible addresses 8 data lines Low 2.0 to 5.5V operating voltage Low supply current (370µA @ 3V) Ultra-low 0.1µA standby current Definable recognition authority True serial encoding Excellent noise immunity Selectable baud rates No programmer required Direct serial interface Small SMD package Latched or momentary outputs Encoder ID output by decoder 224 APPLICATIONS INCLUDE Keyless Entry Door and Gate Openers Security Systems Remote Device Control Car Alarms / Starters Home / Industrial Automation Remote Status Monitoring Lighting Control ORDERING INFORMATION PART # DESCRIPTION LICAL-ENC-MS001 MS Encoder LICAL-DEC-MS001 MS Decoder MDEV-LICAL-MS MS Master Development System MS encoders are shipped in reels of 1,600 Revised 1/28/08 ELECTRICAL SPECIFICATIONS Parameter POWER SUPPLY Operating Voltage Supply Current: At 2.0V VCC At 3.0V VCC At 5.0V VCC Power-Down Current: At 2.0V VCC At 3.0V VCC At 5.0V VCC ENCODER SECTION Input Low Input High Output Low Output High Input Sink Current Output Drive Current SEND High to DATA_OUT ENVIRONMENTAL Operating Temperature Range Designation VCC ICC Min. 2.0 – – – IPDN – – – VIL VIH VOL VOH – – – – 0.0 0.8 x VCC – VCC - 0.7 – – – -40 0.10 0.10 0.20 – – – – – – 1.64 – 0.80 0.85 0.95 0.15 x VCC VCC 0.6 – 25 25 – +125 µA µA µA V V V V mA mA mS °C – – – 2 3 – – – – – – Typical – 240 370 670 Max. 5.5 300 470 780 Units VDC µA µA µA Notes – 1 1 1 RECOMMENDED PAD LAYOUT The MS Series encoders and decoders are implemented in an industry standard 20-pin Shrink Small Outline Package (20-SSOP). The recommended layout dimensions are shown below. 0.047 (1.19) 0.016 (0.41) 0.026 (0.65) 0.234 (5.94) 0.328 (8.33) Figure 2: PCB Layout Dimensions Table 1: Electrical Specifications Notes 1. Current consumption with no active loads. 2. For 3V supply, (0.15 x 3.0) = 0.45V max. 3. For 3V supply, (0.8 x 3.0) = 2.4V min. PRODUCTION CONSIDERATIONS These surface-mount components are designed to comply with standard reflow production methods. The recommended reflow profile is shown below and should not be exceeded, as permanent damage to the part may result. Lead-Free Sn / Pb 275 ABSOLUTE MAXIMUM RATINGS Supply Voltage VCC Any Input or Output Pin Max. Current Sourced By Output Pins Max. Current Sunk By Output Pins Max. Current Into VCC Max. Current Out Of GND Operating Temperature Storage Temperature -0.3 -0.3 to +6.5 to VCC + 0.3 25 25 250 300 to +125 to +150 VDC VDC mA mA mA mA °C °C 250 225 200 260°C Max 240°C Max TEMPERATURE (°C) 175 150 125 100 75 50 25 -40 -65 *NOTE* Exceeding any of the limits of this section may lead to permanent damage to the device. Furthermore, extended operation at these maximum ratings may reduce the life of this device. TIMINGS Baud Rate 2,400 9,600 19,200 28,800 Page 2 0 0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 420 TIME (SECONDS) Initial Start-up 72.62 22.42 13.80 11.00 After Valid Rx 38.62 12.42 7.30 6.00 With RX_PDN (Worst Case) 600+72.62 300+22.42 150+13.80 150+11.00 Figure 3: MS Series Reflow Profile *CAUTION* This product is a static-sensitive component. Always wear an ESD wrist strap and observe proper ESD handling procedures when working with this device. Failure to observe this precaution may result in device damage or failure. Page 3 Table 2: Encoder SEND to Decoder Activation Times (mS) PIN ASSIGNMENTS PIN DESCRIPTIONS Data Lines 1 2 3 4 5 6 7 8 9 10 D6 LICAL-ENC-MS001 D5 D7 D4 SEL_BAUD0 D3 SEL_BAUD1 D2 GND VCC GND VCC GND D1 TX_CNTL D0 DATA_OUT SEND MODE_IND CREATE_ADDR 20 19 18 17 16 15 14 13 12 11 The encoder has eight data lines, D0 through D7. The state of these lines are captured when the SEND line goes high and encoded for transmission. Upon successful reception, these states are reproduced on the outputs of the decoder. SEL_BAUD0 and SEL_BAUD1 These lines are used to select the baud rate of the serial data stream. The state of the lines allows the selection of one of four possible baud rates, as shown in the table. SEL_BAUD1 SEL_BAUD0 Baud Rate (bps) 0 0 1 1 0 1 0 1 2,400 9,600 19,200 28,800 Table 3: Baud Rate Selection Table The baud rate must be set before power up. The encoder will not recognize a change in the baud rate setting after it is on. GND These lines are connected to ground. TX_CNTL This line goes high when the SEND line goes high, and low when the SEND line goes low. This can be used to power up an external RF or infrared transmitter when the encoder is sending data, and power it down when the encoder is asleep. It can also be used to drive a LED for visual transmit indication. Figure 4: MS Series Encoder Pin Assignments Pin Name D0-D7 SEL_BAUD0 SEL_BAUD1 GND TX_CNTL DATA_OUT MODE_IND CREATE_ADDR SEND VCC Pin Number 1, 2, 13, 14, 17-20 3 4 5, 6, 7 8 9 10 11 12 15, 16 I/O I I I — O O O I I — Description Data Input Lines Baud Rate Selection Line Baud Rate Selection Line Ground External Transmitter Control Line Serial Data Output Mode Indicator Output Create Mode Selection Line Encoder Send Data Line Positive Power Supply DATA_OUT The encoder will output a serial data stream on this line. This line can directly interface with all Linx RF transmitter modules. MODE_IND This line is activated while the encoder is in Create Mode, allowing the connection of a LED indicator. The LED will stay on for the entire time the encoder is in Create Mode, indicating that the encoder is creating a new Code Word. CREATE_ADDR When this line is taken high, the encoder will enter Create Mode and randomly generate a new Code Word. This word will be continuously randomized while this line is high, and will be saved as soon as this line is taken low. SEND When this line goes high, the encoder will record the states of the data lines, retrieve the secure Code Word from memory, assemble the packet, and send it as a serial bit stream out of the DATA_OUT line at the baud rate selected by the states of the SEL_BAUD lines. VCC This is the positive power supply. NOTE: None of the input lines have internal pull-up or pull-down resistors. The input lines must always be in a known state (either GND or VCC) at all times or the operation may not be predictable. The designer must ensure that the input lines are never floating, either by using external resistors, by tying the lines directly to GND or VCC, or by use of other circuits to control the line state. Page 4 Page 5 DESIGN CONSIDERATIONS The Linx MS Series encoders and decoders are designed for remote control applications. They provide an easy way to securely register button presses or switch closures over a wireless link. The encoder side turns the status of eight parallel input lines into a secure, encoded, serial bit-stream output intended for transmission via an RF or infrared link. Once received, the decoder decodes, error checks, and analyzes the transmission. If the transmission is authenticated, the output lines are set to replicate the status of the lines on the encoder. Prior to the arrival of the Linx MS Series, encoders and decoders typically fell into one of two categories. First were older generation, low-security devices that transmitted a fixed address code, usually set manually with a DIP switch. These address lines frequently caused the user confusion when trying to match a transmitter to a receiver. Another disadvantage was the possibility that address information could be captured and later used to compromise the system. These concerns resulted in the development of a second type of encoder / decoder that focused on security and utilized encryption to guard against code cracking or code grabbing. Typically, the encoding of each transmission changes based on complex mathematical algorithms to prevent someone from replicating a transmission. These devices gained rapid popularity due to their high security and the elimination of manual switches; however, they imposed some limitations of their own. Such devices typically offer a limited number of inputs, the transmitter and receiver can become desynchronized, and creating relationships and associations between groups of transmitters and receivers is difficult. The Linx product line, which includes the MS and HS Series, is the first product line to offer the best of all worlds. Both series accept up to eight inputs, allowing a large number of buttons or contacts to be connected. The devices also allow relationships among multiple encoders and decoders to be easily created. Security is well provided for. The MS Series uses a random fixed word with 224 possible combinations to give a high level of uniqueness and a reasonable level of security. For applications requiring the highest security, the HS Series, which employs tri-level, maximum-security encryption, should be considered. Encoder transmission protocol and methodology is a critical but often overlooked factor in range and noise immunity. The MS and HS products utilize a true serial data stream rather than the PWM schemes employed by many competitive devices. This allows products based on MS or HS devices to achieve superior range and immunity from interference, edge jitter, and other adverse external influences. One of the most important features unique to the MS and HS products is their ability to establish a unique user identity and profile for the device containing the encoder. In conventional designs, all encoded transmissions are either recognized or denied based on the address. In cases where encoder and decoder addresses match, the state of all data lines is recognized and output. Linx products uniquely allow a user or manufacturer to define which encoder inputs will be acknowledged by each decoder. MS series decoders can store up to 40 system users and unique profiles for each. This allows for an incredible variety of unique relationships among multiple system components and opens the door to product features not previously possible. A PRACTICAL EXAMPLE Consider this practical example: a three door garage houses Dad’s Corvette, Mom’s Mercedes, and Son’s Yugo. With most competitive products, any user’s keyfob could open any garage door as long as the addresses match. In a Linx MS-based system, the keyfobs could easily be configured to open only certain doors (guess which one Son gets to open!) The MS Series also allows for component grouping. Imagine a remote control designed for use in a woodshop. One button could turn on a vacuum, one an air cleaner, and another a light, yet another button could then be user configured to turn on all of them with a single touch. As you can see, the MS Series uniquely combines security and simplicity with the power to create groups and relationships. Manual Address Encoders Advantages ☺ High number of button inputs Disadvantages Low-security fixed code Confusing manual addressing Low number of addresses PWM data output High security vulnerabilities “Rolling Code” Encoders Advantages ☺ Highly secure Eliminates manual address settings Disadvantages Low number of button inputs Encoder and decoder can become unsynchronized Difficult or impossible to create relationships Security vulnerabilities Linx Encoders Advantages ☺ High number of button inputs Highly unique (MS) Highest security available on the market (HS) Eliminates manual address settings Allows for associative relationships Cannot unsynchronize Serial data output Encoder ID is output by the decoder Latched or momentary outputs (MS) External transmitter and receiver control lines Disadvantages Slightly higher cost for some basic applications Security vulnerabilities (MS only) Figure 5: Encoder Comparison Table Page 7 Page 6 ENCODER OPERATION Upon power up, the encoder will set the baud rate based on the state of the SEL_BAUD lines, pull the TX_CNTL line low, and go into a low-power sleep mode. It will remain asleep until either the CREATE_ADDR or the SEND line goes high. These lines will place the encoder in either Create Mode or Send Mode as described in the following sections. Power Up Set Baud Rate Pull The TX_CNTL Line Low CREATE MODE The Create Mode allows the generation of a unique address to ensure the security of transmission and prevent unintentional operation of devices. The MS encoder allows 16,777,216 (224) possible addresses. Creating the address is remarkably straightforward. When the CREATE_ADDR line is pulled high, the encoder randomizes the Code Word continuously until the CREATE_ADDR line is pulled low. Once the encoder registers the low line, the Code Word is saved and the encoder will begin to toggle the MODE_IND line. This will indicate to the user that the encoder is ready to accept the Control Permissions. Control Permissions are set by activating the data lines that the user wants the encoder to have the authority to operate. Pulling the CREATE_ADDR line high again will cause the encoder to save the Control Permissions and go back to sleep. The Code Word will be sent with every transmission when the SEND line is pulled high, but the encoder can only activate the decoder data lines that are authorized by the Control Permissions. The Code Word is learned by an MS Series decoder by placing the decoder into Learn Mode and sending a transmission from the encoder. Please refer to the MS Series Decoder Data Guide for full details. The CREATE_ADDR line can be tied to a button or contact point accessible by the user. With a simple press, the user will generate a unique address that should never again require changing. Some designers may prefer to set a code during production and not provide for change by the user. The MODE_IND line allows for the connection of a LED or other device to indicate to the user that the encoder is in Create Mode. Once the CREATE_ADDR line goes high and the encoder enters Create Mode, the MODE_IND line will go high and stay high until the CREATE_ADDR line goes low. The MODE_IND line is capable of sourcing up to 25mA of current. Is The CREATE_ADDR Line High? YES Sleep NO Is The SEND Line High? YES NO Pull MODE_IND Line High Pull The TX_CNTL Line High Randomize Code Word Get the Data From the Data Lines YES Is the CREATE_ADDR Line High? Compare With Control Permissions NO Pull MODE_IND Line Low Send the Data Packet Save Code Word Is The SEND Line High? NO YES Start Toggling MODE_IND Pull The TX_CNTL Line Low SEND MODE When the SEND line goes high the encoder will enter Send Mode. The encoder will pull the TX_CNTL line high to activate the transmitter, record the state of the data lines, assemble the packet, and send it through the DATA_OUT line. It will continue doing this for as long as the SEND line is high, updating the state of the data lines with each transmission. Once SEND is pulled low the encoder will finish the current transmission, pull TX_CNTL low to deactivate the transmitter, and go to sleep. For simple applications that require only a single input, SEND can be tied directly to the data input line, allowing a single connection. If additional lines are used in this manner, diodes or dual contact switches will be necessary to prevent voltage on one data line from activating all of the data lines. The Application Example section demonstrates the use of diodes for this purpose. Page 8 Time Out? YES NO Save Control Permissions Is the CREATE_ADDR Line High? YES Pull MODE_IND Line Low NO Poll Data Lines & Update Control Permissions Figure 6: MS Series Encoder Flowchart Page 9 APPLICATION EXAMPLE The MS encoder is ideal for registering button presses in remote control applications. An example application circuit is shown in the figure below. SYSTEM EXAMPLE The first step in using the encoder is to set the baud rate using the SPDT switches. Next, a unique Code Word is created by pressing and holding the button connected to the CREATE_ADDR line for as long as desired. While the button is held, the LED will be on indicating that the Code Word is being created. Once the button is released, the LED will start flashing. The data buttons that the encoder is to access are now pressed. Pressing the CREATE_ADDR button again makes the encoder save the new Code Word and Control Permissions, turn off the LED, and go to sleep. The decoder must now learn the Code Word for the system to be operational. Please see the decoder design guide for instructions on how to do this. The MS Series Master Development System implements this system, so please see the User’s Guide for the kit for more system information and circuit schematics. 100k 100k To Transmitter PDN To Transmitter 220 1 2 3 4 5 6 7 8 9 10 D6 LICAL-ENC-MS001 D5 D7 D4 SEL_BAUD0 D3 SEL_BAUD1 D2 GND VCC GND VCC GND D1 TX_CNTL D0 DATA_OUT SEND MODE_IND CREATE_ADDR 20 19 18 17 16 15 14 13 12 11 100k 100k 100k 100k 100k 100k 100k 220 100k ONLINE RESOURCES ® Figure 7: MS Series Encoder Application Circuit In this circuit, SPDT switches are used to select the baud rate so that pull-down resistors are not needed. The data lines are connected to buttons and when any button is pressed, the SEND line is pulled high and causes the encoder to transmit. The diodes are used to prevent the voltage on one data line from appearing on another data line. If only one data line is needed, then it can be tied directly to the SEND line without the need for the diodes. None of the inputs have pull-up or pull-down resistors internally, so 100kΩ pulldown resistors are used on the data lines, SEND, and CREATE_ADDR. These resistors are used to pull the lines to ground when the buttons are not being pressed and ensure that they are always in a known state and not floating. Without these resistors, the state of the lines could not be guaranteed and encoder operation may not be predictable. A LED indicator is attached to the MODE_IND line to provide visual feedback to the user that an operation is taking place. This line will source a maximum of 25mA, so the limiting resistor may not be needed, depending on the LED chosen and the brightness desired. Outgoing encoded data will be sent out of the DATA_OUT line at the baud rate determined by the state of the SEL_BAUD lines. This line can be connected directly to the DATA_IN line of a Linx transmitter, used to modulate an infrared diode, or connected to any other serial transmission medium. The TX_CNTL line is connected to the PDN line of a Linx transmitter so that the module will enter a low power state when not in use. A LED can also be connected to the TX_CNTL line to provide visual indication that the encoder is sending data. In this example, the data lines are pulled high by simple pushbutton switches, but many other methods may be employed. Trace contacts, reed switches or microcontrollers are just some examples of other ways of pulling the data lines high. The flexibility of the encoder combined with the associative options of the matching decoder opens a whole new world of options for creative designers. Page 10 www.linxtechnologies.com • • • • • Latest News Data Guides Application Notes Knowledgebase Software Updates If you have questions regarding any Linx product and have Internet access, make www.linxtechnologies.com your first stop. Our website is organized in an intuitive format to immediately give you the answers you need. Day or night, the Linx website gives you instant access to the latest information regarding the products and services of Linx. It’s all here: manual and software updates, application notes, a comprehensive knowledgebase, FCC information, and much more. Be sure to visit often! www.antennafactor.com The Antenna Factor division of Linx offers a diverse array of antenna styles, many of which are optimized for use with our RF modules. From innovative embeddable antennas to low-cost whips, domes to Yagis, and even GPS, Antenna Factor likely has an antenna for you, or can design one to meet your requirements. Page 11 WIRELESS MADE SIMPLE ® U.S. CORPORATE HEADQUARTERS LINX TECHNOLOGIES, INC. 159 ORT LANE MERLIN, OR 97532 PHONE: (541) 471-6256 FAX: (541) 471-6251 www.linxtechnologies.com Disclaimer Linx Technologies is continually striving to improve the quality and function of its products. For this reason, we reserve the right to make changes to our products without notice. The information contained in this Overview Guide is believed to be accurate as of the time of publication. Specifications are based on representative lot samples. Values may vary from lot-to-lot and are not guaranteed. "Typical" parameters can and do vary over lots and application. Linx Technologies makes no guarantee, warranty, or representation regarding the suitability of any product for use in any specific application. It is the customer's responsibility to verify the suitability of the part for the intended application. NO LINX PRODUCT IS INTENDED FOR USE IN ANY APPLICATION WHERE THE SAFETY OF LIFE OR PROPERTY IS AT RISK. Linx Technologies DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL LINX TECHNOLOGIES BE LIABLE FOR ANY OF CUSTOMER'S INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING IN ANY WAY FROM ANY DEFECTIVE OR NON-CONFORMING PRODUCTS OR FOR ANY OTHER BREACH OF CONTRACT BY LINX TECHNOLOGIES. The limitations on Linx Technologies' liability are applicable to any and all claims or theories of recovery asserted by Customer, including, without limitation, breach of contract, breach of warranty, strict liability, or negligence. Customer assumes all liability (including, without limitation, liability for injury to person or property, economic loss, or business interruption) for all claims, including claims from third parties, arising from the use of the Products. The Customer will indemnify, defend, protect, and hold harmless Linx Technologies and its officers, employees, subsidiaries, affiliates, distributors, and representatives from and against all claims, damages, actions, suits, proceedings, demands, assessments, adjustments, costs, and expenses incurred by Linx Technologies as a result of or arising from any Products sold by Linx Technologies to Customer. Under no conditions will Linx Technologies be responsible for losses arising from the use or failure of the device in any application, other than the repair, replacement, or refund limited to the original product purchase price. Devices described in this publication may contain proprietary, patented, or copyrighted techniques, components, or materials. Under no circumstances shall any user be conveyed any license or right to the use or ownership of such items. © 2008 by Linx Technologies, Inc. The stylized Linx logo, Linx, “Wireless Made Simple”, CipherLinx, and the stylized CL logo are the trademarks of Linx Technologies, Inc. Printed in U.S.A.