DESCRIPTION
The HCS201 from Microchip Technology Inc. is a code hopping encoder designed for secure Remote Keyless Entry (RKE) systems. The HCS201 utilizes the KEELOQ® code hopping technology, incorporating high security, a small package outline and low cost. The HCS201 is a perfect solution for unidirectional remote keyless entry systems and access control systems.

FEATURES
Security
• Programmable 28-bit serial number
• Programmable 64-bit encryption key
• Each transmission is unique
• 66-bit transmission code length
• 32-bit hopping code
• 34-bit fixed code (28-bit serial number, 4-bit button code, 2-bit status)
• Encryption keys are read protected

Operating
• 3.5V-13V operation (2.0V min. using the Step up feature)
• Three button inputs
• 7 functions available
• Selectable baud rate
• Automatic code word completion
• Battery low signal transmitted to receiver
• Non-volatile synchronization data

Other
• Simple programming interface
• On-chip EEPROM
• On-chip oscillator and timing components
• Button inputs have internal pull-down resistors
• Minimum component count
• Synchronous Transmission mode
• Built-in step up regulator