Electrical Characteristics

Symbol

Parameter

Test Conditions

Min.

Typ.

Max.

Unit

Conditions

Operating Voltage

¾

2.0

3

4

V

Operating Current

2V

¾¾

15

¾mA

3V

¾¾

400

¾mA

Modulation Resistance

3.3V

¾¾

320

¾W

LC Input Limiter Voltage

¾¾

¾

6.5

¾

V

Output Data Baud Rate

3V

5

10

15

Kbps

Timing & Code Package

HT6740

Rev. 1.20

3

May 17, 2007

Functional Description

Operation Concept

The reader transmits a 13.56MHz carrier signal from its

antenna, the LC tank on the transponder side converts

the carrier energy to voltage form and supply to the tran-

sponder chip with an internal pump circuit. If the induced

energy is high enough, the pumped voltage reaches the

break-in voltage of the internal RC-oscillator, the tran-

sponder is actuated to transmit its internal data serially

by means of damping the LC tank.

The reader receives the transponder

¢s data by means of

detecting the energy variation on its own antenna, and

recognize the information with a microcontroller.

The HT6740 has a built-in internal Voltage Limiter to

prevent excess power supply and RF levels induced by

the LC tank from damaging the device or causing the

device to function abnormally.

A total of 23 bits of OTP memory space is provided, from

which 6 bits wide are customer programmable, which

can be programmed using the specified programmer

supplied by Holtek. The pre-programmed ICs are also

available upon customer

¢s request.

Anti-Collision Function

HT6740 build in anti-collision function. The probability

which reader could

²find² all (ex.5 tags): Under 10K

baud rate. During 103ms

®0.8293; During 308ms

®0.9950; During 408ms®0.9992 and during 510ms is

0.99995.

Option Function

Option 0: 0 continuous (Default)

1 anti-collision

H T 6 7 4 0

E n e r g y

D a t a

R F o s c

&

C o n t r o l l e r

T r a n s p o n d e r

R e a d e r

C u s t o m e r I D

P r o d u c t

C o d e

( 5 b i t s )

( 6 b i t s )

S y n c . D a t a

( 6 b i t s )

C h e c k

S u m

T o t a l E P R O M s p a c e ( 1 7 b i t s )