hcs301 Microchip Technology Inc., hcs301 Datasheet
hcs301
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hcs301 Summary of contents
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... Code Hopping Encoder OQ DESCRIPTION The HCS301 from Microchip Technology Inc code hopping encoder designed for secure Remote Keyless Entry (RKE) systems. The HCS301 utilizes the K code hopping technology, which incorporates high security, a small package outline and low cost, to make this device a perfect solution for unidirectional remote keyless entry systems and access control systems ...
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... The encoder portion of a keyless entry system is integrated into a transmitter, carried by the user and operated to gain access to a vehicle or restricted area. The HCS301 is meant cost-effective yet secure solution to such systems, requiring very few external components (Figure 2-1). ...
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... As indicated in the block diagram on page one, the HCS301 has a small EEPROM array which must be loaded with several parameters before use; most often programmed by the manufacturer at the time of produc- tion. The most important of these are: • ...
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... HCS301 FIGURE 1-2: BUILDING THE TRANSMITTED CODE WORD (ENCODER) EEPROM Array Crypt Key Sync Counter Serial Number FIGURE 1-3: BASIC OPERATION OF RECEIVER (DECODER) 1 Received Information Button Press Serial Number Information Check for 2 Match Perform Function Indicated by 5 button press NOTE: Circled numbers indicate the order of execution. ...
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... DEVICE OPERATION As shown in the typical application circuits (Figure 2-1), the HCS301 is a simple device to use. It requires only the addition of buttons and RF circuitry for use as the transmitter in your security application. A description of each pin is given in Table 2-1. Note: When V > 9.0V and driving low capaci- DD tive loads, a resistor with a minimum value ...
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... Word Transmission Stop DS21143B-page 6 3.0 EEPROM MEMORY ORGANIZATION The HCS301 contains 192 bits (12 x 16-bit words) of EEPROM memory (Table 3-1). This EEPROM array is used to store the encryption key information, synchronization value, etc. Further descriptions of the memory array is given in the following sections. TABLE 3-1: WORD ...
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... Figure 4-2). This allows the system designer to imple- ment the secure learn feature or use this fixed code word as part of a different key generation/tracking pro- cess. 2001 Microchip Technology Inc. HCS301 3.6 CONFIG (Configuration Word) The Configuration Word is a 16-bit word stored in EEPROM array that is used by the device to store information used during the encryption process, as well as the status of option configurations ...
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... DS21143B-page 8 3.6.4 LOW VOLTAGE TRIP POINT SELECT The low voltage trip point select bit is used to tell the HCS301 what will be used by the device to determine when to send the voltage low signal to the receiver. When this bit is set to a one, the 12V ...
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... TRANSMITTED WORD 4.1 Code Word Format The HCS301 code word is made up of several parts (Figure 4-1). Each code word contains a 50% duty cycle preamble, a header, 32 bits of encrypted data and 34 bits of fixed data followed by a guard period before another code word can begin. Refer to Table 8-4 for code word timing ...
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... HCS301 4.3 Synchronous Transmission Mode Synchronous Transmission mode can be used to clock the code word out using an external clock. To enter Synchronous Transmission mode, the Pro- gramming mode start-up sequence must be executed as shown in Figure 4-3. If either set on the falling edge of S2 (or S3), the device enters Synchro- nous Transmission mode ...
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... Section 3.4.1). Setting this bit high will enable the func- tion (turn Auto-shutoff function on) and setting the bit low will disable the function. Time-out period is approx- imately 25 seconds. 2001 Microchip Technology Inc. HCS301 5.6 Seed Transmission In order to increase the level of security in a system possible for the receiver to implement what is known as a secure learn function ...
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... HCS301 5.7 Blank Alternate Code Word Federal Communications Commission (FCC) part 15 rules specify the limits on worst case average funda- mental power and harmonics that can be transmitted in a 100 ms window. For FCC approval purposes, it may therefore be advantageous to minimize the transmis- sion duty cycle. This can be achieved by minimizing the duty cycle of the individual bits as well as by blanking out consecutive code words ...
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... PROGRAMMING THE HCS301 When using the HCS301 in a system, the user will have to program some parameters into the device including the serial number and the secret key before it can be used. The programming cycle allows the user to input all 192 bits in a serial data stream, which are then stored internally in EEPROM ...
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... HCS301 TABLE 6-1: PROGRAMMING/VERIFY TIMING REQUIREMENTS V = 5.0V ± 10%, 25 °C ± 5 °C DD Parameter Symbol Program mode setup time Hold time 1 Hold time 2 Bulk Write time Program delay time Program cycle time Clock low time Clock high time Data setup time Data hold time Data out valid time Note 1: Typical values - not tested in production ...
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... INTEGRATING THE HCS301 INTO A SYSTEM Use of the HCS301 in a system requires a compatible decoder. This decoder is typically a microcontroller with compatible firmware. Microchip will provide (via a license agreement) firmware routines that accept transmissions from the HCS301 and decrypt the hopping code portion of the data stream. These routines provide system designers the means to develop their own decoding system ...
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... HCS301 7.2 Decoder Operation Figure 7-2 summarizes normal decoder operation. The decoder waits until a transmission is received. The received serial number is compared to the EEPROM table of learned transmitters to first determine if this transmitter’s use is allowed in the system. If from a learned transmitter, the transmission is decrypted using the stored crypt key and authenticated via the discrimination bits for appropriate crypt key usage ...
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... FIGURE 7-3: SYNCHRONIZATION WINDOW Entire Window rotates to eliminate use of previously used codes 2001 Microchip Technology Inc. Blocked Window (32K Codes) Stored Synchronization Counter Value Double Operation (resynchronization) Single Operation Window Window (32K Codes) (16 Codes) HCS301 DS21143B-page 17 ...
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... HCS301 8.0 ELECTRICAL CHARACTERISTICS TABLE 8-1: ABSOLUTE MAXIMUM RATINGS Symbol V Supply voltage Output voltage OUT I Max output current OUT T Storage temperature STG T Lead soldering temp LSOL V ESD Note: Stresses above those listed under “ABSOLUTE MAXIMUM RATINGS” may cause permanent damage to the device ...
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... FIGURE 8-1: TYPICAL ICC CURVE OF HCS301 WITH EXTERNAL RESISTORS 12.0 10.0 8.0 6.0 4.0 2.0 0 12.0 10.0 8.0 6.0 4.0 2.0 0 12.0 10.0 8.0 6.0 4.0 2.0 0 2001 Microchip Technology Inc. 50 External [V] BAT 1 External [V] BAT 2 External [V] BAT HCS301 LEGEND Typical Maximum ...
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... HCS301 FIGURE 8-2: POWER-UP AND TRANSMIT TIMING Button Press Detect PWM Output Button Input Sn TABLE 8-3: POWER-UP AND TRANSMIT TIMING V = +3.5 to 13.0V DD Commercial(C): Tamb = 0°C to +70°C Industrial(I): Tamb = -40°C to +85°C Symbol Parameter T Time to second button press BP T Transmit delay from button detect ...
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... HCS301 Bit 0 Bit 1 Header Data Bits E Status RPT LOW Guard Time 1 out of 4 Max. Min. Typ. Max. Units 330 65 100 165 s 990 195 300 495 s 7.6 1.5 2.3 3 ...
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... HCS301 FIGURE 8-6: HCS301 TE VS. TEMP (BY CHARACTERIZATION ONLY) 1.7 1.6 1.5 1.4 1.3 1 1.1 1.0 0.9 0.8 0.7 0.6 -50 -40 -30 -20 - DS21143B-page 3. 5. 5.0V DD Typical Min. E TEMPERATURE 2001 Microchip Technology Inc. ...
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... For PICmicro device marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. For QTP devices, any special marking adders are included in QTP price. 2001 Microchip Technology Inc. HCS301 Example HCS301 XXXXXNNN 0025 Example HCS301 XXX0025 NNN DS21143B-page 23 ...
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... HCS301 9.2 Package Details 8-Lead Plastic Dual In-line (P) - 300 mil (PDIP Dimension Limits Number of Pins Pitch Top to Seating Plane Molded Package Thickness Base to Seating Plane Shoulder to Shoulder Width Molded Package Width Overall Length Tip to Seating Plane Lead Thickness Upper Lead Width ...
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... A2 .052 .056 .061 A1 .004 .007 .010 E .228 .237 .244 E1 .146 .154 .157 D .189 .193 .197 h .010 .015 .020 L .019 .025 .030 .008 .009 .010 B .013 .017 .020 HCS301 A2 MILLIMETERS MIN NOM MAX 8 1.27 1.35 1.55 1.75 1.32 1.42 1.55 0.10 0.18 0.25 5.79 6.02 6.20 3.71 3.91 3.99 4.80 4.90 5.00 0.25 0.38 0.51 0.48 0.62 0. 0.20 0.23 0.25 0.33 0.42 0. ...
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... HCS301 ON-LINE SUPPORT Microchip provides on-line support on the Microchip World Wide Web (WWW) site. The web site is used by Microchip as a means to make files and information easily available to customers. To view the site, the user must have access to the Internet and a web browser, such as Netscape or Microsoft Explorer ...
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... Is there any incorrect or misleading information (what and where)? 7. How would you improve this document? 8. How would you improve our software, systems, and silicon products? 2001 Microchip Technology Inc. Total Pages Sent FAX: (______) _________ - _________ N Literature Number: DS21143B HCS301 DS21143B-page 27 ...
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... HCS301 HCS301 PRODUCT IDENTIFICATION SYSTEM To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office. HCS301 - /P Package: Temperature Range: Device: Sales and Support Data Sheets Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recommended workarounds ...
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... Use of Microchip’s products as critical com- ponents in life support systems is not authorized except with express written approval by Microchip. No licenses are con- veyed, implicitly or otherwise, under any intellectual property rights. 2001 Microchip Technology Inc. Trademarks The Microchip name and logo, the Microchip logo, FilterLab ...
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... Centro Direzionale Colleoni Palazzo Taurus Colleoni 1 20041 Agrate Brianza Milan, Italy Tel: 39-039-65791-1 Fax: 39-039-6899883 United Kingdom Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820 10/01/01 2001 Microchip Technology Inc. ...