HCS200-IP Microchip Technology, HCS200-IP Datasheet
HCS200-IP
Related parts for HCS200-IP
HCS200-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 HCS200 a very secure unit. The HCS200 provides an easy to use serial interface for programming the necessary security keys, system parameters, and configuration data. ...
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... Transmission of the random seed can be dis- abled after learning is completed. The HCS200 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 HCS200. Section 7.0 provides more detail on integrating the HCS200 into a total sys- tem. Before a transmitter can be used with a particular receiver, the transmitter must be ‘learned’ by the receiver ...
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... V 8 Positive supply voltage connec- DD tion DS40138A-page 4 The high security level of the HCS200 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 algo- rithm obscures the information in such a way that even if the ...
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... EEPROM MEMORY ORGANIZATION The HCS200 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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... S2 should not be toggled until all internal processing has been completed as shown in Figure 4-3. Max 4.3 Code Word Organization The HCS200 transmits a 66-bit code word when a button is pressed. The 66-bit word is constructed from Min a Fixed Code portion and an Encrypted Code portion 100 (Figure 4-2). ...
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... Encrypted Code Data 28-bit Button Discrimina- Serial Number Status tion bits (4 bits) (12 bits) Serial Number and 32 bits of Encrypted Data + Button Status (32 bits) Serial Number 28 Preliminary HCS200 Guard Time T T FIX G 16-bit Sync Value 66 bits of Data Transmitted Data Word Sync Counter 16 16 ...
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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 HCS200 which is stored in EEPROM and can only be transmitted when all three 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 HCS200 When using the HCS200 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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... HCS200 7.0 INTEGRATING THE HCS200 INTO A SYSTEM Use of the HCS200 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 HCS200 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 HCS200 SYNCHRONIZATION WINDOW Blocked 32K Codes Current Position Open 32K Codes Current window of 16 codes DS40138A-page 11 ...
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... HCS200 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 HCS200 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 [V] BAT 1K External [V] BAT 2K External [V] BAT Preliminary HCS200 LEGEND Typical ...
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... HCS200 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 to 13.0V 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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... HOP T Fixed code duration FIX T Guard Time G — Total Transmit Time — PWM data rate Note: The timing parameters are not tested but derived from the oscillator clock. FIGURE 8-6: HCS200 TE VS. TEMP (BY CHARACTERIZATION) 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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... HCS200 HCS200 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. HCS200 - /P Package: Temperature Range: Device: AMERICAS Corporate Office Microchip Technology Inc. 2355 West Chandler Blvd. ...