Philips Semiconductors
Product Profile PCF7936AS
July 1998
Security Transponder, HITAG 2
Features
• Programmable Security Transponder
• 64/32 bit mutual authentication
• 32 bit unique device dentification number
• 48 bit Secret Key
• Fast authentication, 39 ms
• 128 bit non-volatile user memory (EEPROM)
• EEPROM access in plain or cipher mode
• EEPROM read/write protection capabilities
• Read Only modes for downward compatibility
• Excellent device sensitivity in read and write
mode, 35 µT
• 20 year EEPROM data retention
• Leadless stick shaped plastic package
General Description
The PCF7936, HITAG 2 is a programmable Security
Transponder employing mutual authentication ideally
suited for contactless authentication and memory
access between a basestation and the transponder.
The transponder meets the security and performance
requirements of modern vehicle immobiliser
applications. Excellent device sensitivity (large
distance) and short authentication time ensure easy
application and outstanding system performance.
The transponder provides 256 bit of non-volatile
memory (EEPROM) from which 128 bit are reserved
for user data storage. User data and configuration data
may be exchanged in cipher mode for advanced pre-
personalisation techniques. Memory access flags
support read and/or write protection of data.
The device performs a fast mutual authentication
algorithm, employing a Random Number, Secret Key
and Passwords. In addition the HITAG 2 features a
factory programmed 32 bit unique identification number
to enable unambiguously device identification.
The HITAG 2 features two Read Only modes for
downward compatibility with common Read Only
systems.
The transponder power supply and system clock is
derived from the magnetic component of the RF field
generated by the basestation. Due to low power
consumption the HITAG 2 provides excellent sensitivity
in read and write mode.
The transponder is assembled in a small leadless stick
shaped plastic package.
Block Diagram Stick Package Outline
PCF7936AS
Clock Recovery
Demodulator
Modulator
Rectifier
Voltage Limiter
Power-On Reset
Data Acquisition
EEPROM
Access Control
Calculation Unit
EEPROM
Transponder IC
Control Logic Contactless Interface
L C
( without Scale )
Cross Section A-A
A
A
2,9-3,05
4,9-5,1 1,9-2,1
4,4 - 4,6
11,9-12,1
5,9-6,1
All Dimensions [mm]
