TDA8006 datasheet(26/40 Pages) PHILIPS

26 / 40 page

2000 Feb 21

Philips Semiconductors

Product speciﬁcation

Multiprotocol IC Card coupler

TDA8006

handbook, full pagewidth

MGR238

OFF

CMDVCC

RST

I/O

VCC

CLK

Fig.14 Emergency deactivation sequence after VCC short circuited to ground.

Auxiliary contacts C4 and C8

The auxiliary contacts C4 and C8 are controlled by ports

P34 and P35 through two identical pseudo-bidirectional

I/O lines.

In the Idle state, port P34 is pulled HIGH to VDD by an

integrated 20 k

Ω resistor and C4 is pulled HIGH to VCC by

an integrated 10 k

Ω resistor. This allows operation with a

VCC value of 3 V and a VDD value of 5 V. The first side on

which a falling edge occurs becomes the master.

An anti-latch circuit disables the detection of a falling edge

on the other side, which becomes the slave.

After a delay of approximately 200 ns (td), the N transistor

on the slave side is turned on which transmits the ‘0’

present on the master side. When the master side goes

back to logic 1, the P transistor on the slave side is turned

on during td, and then both sides return to their idle states.

The maximum frequency on the I/O lines is 1 MHz.

TDA8006 Datasheet(PDF) 26 Page - NXP Semiconductors