GENERAL DESCRIPTION

The HCS473 combines the patented KEELOQ code hopping technology and bi-directional transponder challenge-and-response security into a single chip solution for logical and physical access control.

The three-input transponder interface allows the combination of three orthogonal transponder antennas, eliminating the directionality associated with traditional single antenna transponder systems.

FEATURES

Encoder Security

? Read protected 64-bit encoder key

? 69-bit transmission length

? 60-bit, read protected seed for secure learning

? Programmable 32-bit serial number

? Non-volatile 16/20-bit synchronization counter

Encoder Operation

? 2.05V to 5.5V operation

? Four switch inputs – up to 15 functions codes

? PWM or Manchester modulation

? Selectable Baud Rate (416 - 5,000 bps)

? Transmissions include button queuing information

? PLL interface

Transponder Security

? 2 read protected 64-bit Challenge/Response keys

? Two IFF encryption algorithms

? 16/32-bit Challenge/Response

? Separate Vehicle ID and Token ID

? 2 vehicles supported

? CRC on all communication

Transponder Operation

? Three sensitive transponder inputs

? Bi-directional transponder communication

? Transponder in/RF out operation

? Anticollision of multiple transponders

? Intelligent damping for high Q-factor LC-circuits

? Low battery operation

? Passive proximity activation

? 64-bit secure user EEPROM

? Fast reaction time

Peripherals

? Low Voltage Detector

? On-board RC oscillator with ±10 variation

Typical Applications

? Passive entry systems

? Automotive remote entry systems

? Automotive alarm systems

? Automotive immobilizers

? Gate and garage openers

? Electronic door locks (Home/Office/Hotel)

? Burglar alarm systems

? Proximity access control

? Passive proximity authentication