HCS301-IP Microchip Technology, HCS301-IP Datasheet
HCS301-IP
Related parts for HCS301-IP
HCS301-IP Summary of contents
Page 1
... The encryption key, serial number, and configuration data are stored in EEPROM which is not accessible via any external connection. This makes the HCS301 a very secure unit. The HCS301 provides an easy to use serial interface for programming the necessary security keys, system parameters, and configuration data. ...
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... It must be pointed out that there exists some third-party patents on learn- ing strategies and implementation. The HCS301 is a code hopping encoder device that is designed specifically for keyless entry systems, primarily for vehicles and home garage door openers meant cost-effective, yet secure solution to such systems ...
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... Any type of controller may be used as a receiver, but it is typically a microcontroller with compatible firmware that allows the receiver to operate in conjunction with a transmitter, based on the HCS301. Section 7.0 provides more detail on integrating the HCS301 into a total system. Before a transmitter can be used with a particular receiver, the transmitter must be ‘learned’ by the receiver ...
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... LED during transmission V 8 Positive supply voltage DD connection DS21143A-page 4 The high security level of the HCS301 is based on the pat- ented K L technology. A block cipher based on a block EE OQ length of 32 bits and a key length of 64 bits is used. The algorithm obscures the information in such a way that even ...
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... 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: EEPROM MEMORY MAP WORD MNEMONIC ...
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... HCS301 3.6 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. Further explanations of each of the bits are described in the following sections. ...
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... Figure 4-4. 4.3 Code Word Organization The HCS301 transmits a 66-bit code word when a button is pressed. The 66-bit word is constructed from a Fixed Code portion and an Encrypted Code portion (Figure 4-2). The Encrypted Data is generated from 4 button bits, 2 overfl ...
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... HCS301 FIGURE 4-1: CODE WORD TRANSMISSION FORMAT LOGIC ‘0’ LOGIC ‘1’ Bit Period Preamble T P FIGURE 4-2: CODE WORD ORGANIZATION Fixed Code Data Repeat V Button LOW (1 bit) (1 bit) Status (4 bits) 1 bit of Status + 1 bit Fixed FIGURE 4-3: SYNCHRONOUS TRANSMISSION MODE PWM S2(S3) “01,10,11” ...
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... Code word completion is an automatic feature that makes sure that the entire code word is transmitted, even if the button is released before the transmission is complete. The HCS301 encoder powers itself up when a button is pushed and powers itself down after the command is finished, if the user has already released the button ...
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... 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. This can be done by utilizing the seed value on the HCS301 which is stored in EEPROM and can only be transmitted when all four button inputs are pressed at the same time (Table 5-1). Instead of the normal key generation method being used to create the encryption key, this seed value is used ...
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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 7.0 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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... FIGURE 7-3: Entire Window rotates to eliminate use of previously used codes and Preliminary HCS301 SYNCHRONIZATION WINDOW Blocked 32K Codes Current Position Open 32K Codes Current window of 16 codes DS21143A-page 13 ...
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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 1996 Microchip Technology Inc. 50 External [V] BAT 1K External [V] BAT 2K External [V] BAT Preliminary HCS301 LEGEND Typical ...
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... HCS301 FIGURE 8-2: POWER UP AND TRANSMIT TIMING Button Press Detect PWM Sn TABLE 8-3: POWER UP AND TRANSMIT TIMING REQUIREMENTS V = +3.5 to13.0V DD Commercial (C): Tamb = +70 C Industrial (I): Tamb = - +85 C Parameter Time to second button press Transmit delay from button detect Debounce delay Auto-shutoff time-out period Note the time in which a second button can be pressed without completion of the fi ...
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... Fixed code duration 102 FIX T Guard Time G — Total Transmit Time 270 — PWM data rate Note: The timing parameters are not tested but derived from the oscillator clock. FIGURE 8-6: HCS301 TE VS. TEMP (BY CHARACTERIZATION ONLY) 1.7 1.6 1.5 1.4 1.3 1.2 TE 1.1 1.0 0.9 0.8 0.7 0.6 -50 -40 -30 -20 - 1996 Microchip Technology Inc ...
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... HCS301 NOTES: DS21143A-page 18 Preliminary 1996 Microchip Technology Inc. ...
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... NOTES: 1996 Microchip Technology Inc. Preliminary HCS301 DS21143A-page 19 ...
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... HCS301 HCS301 Product Identification System To order or to obtain information (e.g., on pricing or delivery), please use the listed part numbers, and refer to the factory or the listed sales offices. HCS301 - /P Package: Temperature Range: Device: AMERICAS Corporate Office Microchip Technology Inc. 2355 West Chandler Blvd. ...