DS1990A RW1990 TM1990A Ibutton Key door lock Key Tag TM Card

High Quality DS1990A 64-bit ROM Ibutton TM Smart Key Cards for Door Lock

DS 1990A-F4 Serial Number iButton is a rugged data carrier that acts as an electronic registration number for automatic identification. We provide Ibuttons, keyfobs, wristband for different use style.

The 1990A-F4 is smaller size compared with 1990A-F5, other function is the same. The button size is 10mm dia, height 4mm. The key total size is 38x15mm.

1990A
* Upgrade of DS1990 allows multiple Serial
* Number iButtons to reside on a common bus
* Unique 48bit serial number
* Low-cost electronic key for access control
* 8-bit CRC for checking data integrity
* Can be read in less than 5 ms
* Operating temperature range of -40C to +85C

The basic principles of TM cards: A TM card is similar to a button battery in shape and can be inlaid into a card, key button and other objects.

You can replace the data line, address line, control line and power line with a single line so that TM card achieves single line communication through a multi-function device. When the host is powered, TM card gives the response to the host through switching the impedances between 50Ω and 500,000Ω. The lengths of time the signal is pulled down(long or short) show the digital logics(long=1, short=0). Due to the range of witching impedances is 1-10,000, the resistances of the contact points will not affect the identification of the digital signals.

Due to whether the Memory in TM card is encrypted or not, TM card can be divided into encrypted TM card and non-encrypted TM card.

Most of TM cards are non-encrypted.

TM1990-F5 card is an encrypted card: which is divided into three separate encrypted sectors. Each encrypted sector has its own password and the three sectors can be respectively used for three separate purposes. DS1982 card is programmable.

TM card’s encrypted method is different from Contactless IC Encrypted cards: The former has 64-bit password without the function of error calculation, while the latter has shorter password and the function of error calculation. If you forget your password by chance, you can reuse your TM card after re-initializing it, but the information in your card will be automatically rewritten.

Product Specification

If you are interested in this TM card, we surely welcome your inquiry!