Ic card interface tda8002c – Philips TDA8002C User Manual

Page 14

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1999 Oct 12

14

Philips Semiconductors

Product specification

IC card interface

TDA8002C

D

EACTIVATION SEQUENCE

When a session is completed, the microcontroller sets the
CMDVCC line to HIGH state or MODE line to LOW state.
The circuit then executes an automatic deactivation
sequence by counting the sequencer down and thus end
in the Idle mode.

Figures 13 and 14 illustrate the deactivation sequence as
follows:

1. RST goes LOW (t

11

t

10

)

2. CLK is stopped (t

12

= t

11

+

1

2

T)

3. I/O, AUX1 and AUX2 fall to zero (t

13

= t

11

+ T)

4. V

CC

falls to zero (t

14

= t

11

+ 1

1

2

T); a special circuit

ensures that I/O remains below V

CC

during the falling

slope of V

CC

5. VUP falls (t

15

= t

11

+ 5T).

handbook, full pagewidth

FCE479

CMDVCC

VUP

OSC_INT/64

VCC

I/O

CLK

RSTIN

RST

LOW

tde

t10

t11

t12

t13

t14

t15

Fig.13 Deactivation sequence

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