RFID key­fobs are access con­trol tokens that con­tain RFID chips. RFID key­fobs are used for con­tact­less iden­ti­fi­ca­tion or to enable access to build­ings and secure areas. They con­tain unique ID codes in RFID tags that can be read by RFID read­ers to iden­ti­fy the key­fob hold­er and grant or deny access. RFID key­fobs are a pop­u­lar method for access con­trol in offices, gyms, apart­ments, park­ing garages, etc. They are reusable and pro­gram­ma­ble, you can repro­gram the RFID tags with new access codes or access priv­i­leges as need­ed.

Para­me­ters of Contact/Contactless chip

Chip mod­el	Brand	Type	Fre­quen­cy	Mem­o­ry	Read-Write time	Data con­ser­va­tion	Pro­to­cal
Mifare S50	NXP	Con­tact­less	13.56Mhz	1Kbyte	100000	10 years	ISO 14443A
Mifare S70	NXP	Con­tact­less	13.56Mhz	4Kbyte	100000	10 years	ISO 14443A
Mifare des­fire 2k	NXP	Con­tact­less	13.56Mhz	2Kbyte	500000	10 years	ISO 14443A
Mifare des­fire 4k	NXP	Con­tact­less	13.56Mhz	4Kbyte	500000	10 years	ISO 14443A
Mifare des­fire 8k	NXP	Con­tact­less	13.56Mhz	8Kbyte	500000	10 years	ISO 14443A
Mifare ultra­light	NXP	Con­tact­less	13.56Mhz	64byte	100000	5 years	ISO 14443A
Mifare PLUSS2K/X2K	NXP	Con­tact­less	13.56Mhz	2byte	200000	10 years	ISO 14443A
M1 PLUSS2K/4K	NXP	Con­tact­less	13.56Mhz	4byte	200000	10 years	ISO 14443A
I‑CODE SLI	NXP	Con­tact­less	13.56Mhz	1024bits	100000	40 years	ISO15693
HITAG1	NXP	Con­tact­less	125KHZ	2048bits	100000	10 years	ISO11784/785
HITAG2	NXP	Con­tact­less	125KHZ	256bits	100000	10 years	ISO11784/785
HITAG3	NXP	Con­tact­less	125KHZ	256/2048bits	100000	10 years	ISO11784/785
FM11RF08	FUDAN	Con­tact­less	13.56Mhz	1Kbyte	100000	10 years	ISO14443A
FM11RF32	FUDAN	Con­tact­less	13.56Mhz	4Kbyte	100000	10 years	ISO14443A
FM1208 series	FUDAN	Con­tact­less	13.56Mhz	8Kbyte	100000	10 years	ISO14443A
FM1204	FUDAN	Con­tact­less	13.56Mhz	4Kbyte	100000	10 years	ISO14443A
Legic256	Legic	Con­tact­less	13.56Mhz	256byte	100000	10 years
Ti2048	TI	Con­tact­less	13.56Mhz	256byte	100000	10 years	ISO15693
ID4001/4100	RUIXIN	Con­tact­less	125KHZ	–	100000	10 years	–
EM4200/4305	EM	Con­tact­less	125KHZ	–	100000	10 years	–
T5577	ATMEL	Con­tact­less	125KHZ	330bits	100000	10 years	ISO1178/785
U‑CODE HSL	HSL	Con­tact­less	915KHZ	2048bits	100000	10 years	ISO18000-6B
Alien9662(H3)	ATMEL	Con­tact­less	915KHZ	96bit EPC/512Bit user­mem­o­ry	100000	10 years	ISO18000-6C
Fm1216 series	FUDAN	Con­tact­less	13.56Mhz	16Kbyte	100000	10 years	ISO14443A
SLE4442/5542	SIEMENS	Con­tact	–	256byte	100000	10 years	ISO7816
SLE4428/5528	SIEMENS	Con­tact	–	1byte	100000	10 years	ISO7816
45DB041	ATMEL	Con­tact	–	528Kbyte	100000	10 years	ISO7816
AT88SC102	ATMEL	Con­tact	–	1024bits	100000	10 years	ISO7816
AT88SC1604	ATMEL	Con­tact	–	5704bits	100000	10 years	ISO7816
AT88SC153	ATMEL	Con­tact	–	2048bits	100000	10 years	ISO7816
24 series		Con­tact	–	1k-64k­bits	100000	10 years	ISO7816