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

4,9-5,1

1,9-2,1

11,9-12,1

All Dimensions [mm]