HCS500-I Datasheet, PDF (1/34 Pages) Microchip Technology – KEELOQ Code Hopping Decoder

HCS500
KEELOQ^® Code Hopping Decoder
FEATURES
Security
• Encrypted storage of manufacturer’s code
• Encrypted storage of crypt keys
• Up to seven transmitters can be learned
• KEELOQ code hopping technology
• Normal and Secure learning mechanisms
Operating
• 3.0V—5.5V operation
• Internal oscillator
• Auto bit rate detection
Other
• Stand-alone decoder chipset
• External EEPROM for transmitter storage
• Synchronous serial interface
• 1 Kbit user EEPROM
• 8-pin DIP/SOIC package
Typical Applications
• Automotive remote entry systems
• Automotive alarm systems
• Automotive immobilizers
• Gate and garage openers
• Electronic door locks
• Identity tokens
• Burglar alarm systems
Compatible Encoders
All KEELOQ encoders and transponders configured for
the following setting:
• PWM modulation format (1/3-2/3)
• TE in the range from 100us to 400us
• 10 x TE Header
• 28-bit Serial Number
• 16-bit Synchronization counter
• Discrimination bits equal to Serial Number 8 LSbs
• 66- to 69-bit length code word.
DESCRIPTION
The Microchip Technology Inc. HCS500 is a code hop-
ping decoder designed for secure Remote Keyless
Entry (RKE) systems. The HCS500 utilizes the pat-
ented KEELOQ^® code hopping system and high security
learning mechanisms to make this a canned solution
when used with the HCS encoders to implement a uni-
directional remote and access control systems. The
HCS500 can be used as a stand-alone decoder or in
conjunction with a microcontroller.
PACKAGE TYPE
PDIP, SOIC
VDD 1
EE_CLK 2
EE_DAT 3
MCLR 4
8 VSS
7 RFIN
6 S_CLK
5 S_DAT
BLOCK DIAGRAM
RFIN
Reception Register
External
EEPROM
EE_DAT
EE_CLK
CONTROL
DECRYPTOR
S_DAT
S_CLK
OSCILLATOR
MCLR
The manufacturer’s code, crypt keys, and synchroniza-
tion information are stored in encrypted form in external
EEPROM. The HCS500 uses the S_DAT and S_CLK
inputs to communicate with a host controller device.
The HCS500 operates over a wide voltage range of
3.0 volts to 5.5 volts. The decoder employs automatic
bit-rate detection, which allows it to compensate for
wide variations in transmitter data rate. The decoder
contains sophisticated error checking algorithms to
ensure only valid codes are accepted.
© 2002 Microchip Technology Inc.
DS40153C-page 1