Philips TDA8002C - Manual (Page 14)

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