China Touch Memory Serial Number iButton Ds1990/ Rewritable RW1990 iButton Cards, Find details about China Ds1990A, TM1990A from Touch Memory Serial Number iButton Ds1990/ Rewritable RW1990 iButton Cards
Description
The TM1990A-F5 electronic iButton key with unique 64-bit code is a full quality analog of Dallas/Maxim DS1990A-F5 iButtons. Designed for access control systems each key has a unique family code that is recorded while the key is being produced and the code cannot be overwritten.
While manufacturing such devices in the factory, the number is directly assigned directly to the production line. Each TM1990A-F5 is assigned a unique identification code consisting of numbers and letters. The approximate number of combinations - 4 billion. Therefore the chance to guess the key from the entrance is practically zero. The key contains a number. It can not be charged or magnetized. But it can be stored in the memory controller, which controls the door to the entrance or office.
When you touch the ibutton reader with a TM1990A-F5 key, it reads this code and passes it to the controller, which checks with the internal memory for its presence in the database. If the identifier with the code is found, the access rights are checked (in some systems there may be time constraints) and give the actuators (locks, latches, latches or relays) the command to open/close.
The main advantages of TM1990A-F5: Electronic keys provide 100% uniqueness. The use of such tablets can significantly reduce the cost of programming a large number of keys for staff. TM1990A-F5 is for use as a workpiece for copying is not intended. (To copy the DS1990A and TM1990A keys, use our RW1990 copy iButtons).
Key Features