TM1990A iButton Master Access Control Card Readers

TM1990A iButton Master Access Control Card Readers

The TM1990A is a CMOS electronic key device that contains a unique 64-bit digital code stored in internal nonvolatile memory. Communication with the device is performed through the 1-Wire protocol, requiring only a DATA line and a common GND connection. The device supports ROM search functionality, allowing multiple TM1990A devices to share the same 1-Wire bus.

During operation, a master controller initializes the 1-Wire bus and communicates with the TM1990A using ROM function commands. The device can provide its group code, unique 48-bit serial number, and 8-bit CRC, making it suitable for electronic identification and access-control applications.

Features:

• Unique electronic identification.
• Nonvolatile internal memory.
• 1-Wire communication interface.
• Requires only one data connection and common ground.
• Supports ROM search on a shared 1-Wire bus.
• Contact-based electronic key operation.
• Compatible with DS1990-type identification systems.
• Compact iButton form factor.
• Suitable for master-controlled identification systems.

Specifications:

Applications:

• Access-control systems.
• Electronic door locks.
• Electronic key systems.
• User identification
• Equipment identification.
• Security systems.
• Attendance systems.
• Industrial access systems.
• Embedded identification systems.
• Multi-device 1-Wire identification networks.

Package Includes:

• 1x TM1990A iButton Master Access Control Card Readers.

Documents:

• TM1990A Datasheet.