HITAG 1 based RFID CARD transponders are highly integrated and do not need any additional components beside the external coil.
Data between Key (RWD) and transponder is transmitted bidirectionally, in Half Duplex Mode. The HITAG 1 transponder IC offers also an encrypted data transmission.
The AntiCollision (AC) Mode, which is used mainly in long range operation, allows to handle several transponders that are at the same time in the communication field of the antenna, thus achieving highest operating reliability and permitting to handle several transponders quickly and simultaneously.
The HITAG 1 transponder IC provides two protocol modes, Standard and Advanced Mode. The Advanced Protocol Mode operates compared to the Standard Protocol Mode with an increased number of Startbits and a 8-bit Cyclic Redundancy Check (CRC) sent by the transponder IC at read operations.
HITAG 1 transponder IC offer a memory of 2 kbit.

Features and benefits
Identification transponder for use in contactless applications
Operating frequency 125 kHz
Data transmission and energy supply via RF link, no internal battery
Non-volatile memory of 2 kbit
Organized in 64 pages, 4 bytes each
10 years non-volatile data retention
100000 erase/write cycles
Selective read/write protection of memory content
Mutual authentication function

Applications
Logistics
Asset tracking
Gas cylinder ID
Industrial automation

The air rfid inlay frequency (RF) CPU CPU card is often referred to as the active card, is on such basis as the CPU card increased the RF transceiver circuit. CPU card possesses his own operating system, COS is truly real smart CARDS.