RW1990 Ibutton
RW1990 Ibutton adopts single-wire protocol communication, and completes data reading and writing through instant touch. It not only has the ease of operation of non-contact IC cards, but also has the cheapness of contact IC cards. It is one of the most cost-effective IC cards at present.
The RW1990 Ibutton 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.
