
2003 Jul 04
31
Philips Semiconductors
Product specification
USB smart card reader (OTP or ROM)
TDA8030; TDA8031
8.3
ISO7816 SECURITY
8.3.1
I
NTRODUCTION
Thecorrectsequenceduringactivationanddeactivationof
thecardsisensuredthroughaspecificsequencer,clocked
by a division ratio of the internal oscillator.
Activation(STARTbitHIGHinthePowerControlRegister)
is only possible if the card is present (PRES active HIGH)
and if the supply voltage is correct (supervisor not active).
The presence of the card is signalled to the microcontroller
by the Hardware Status Register (HSR).
Bit PRL in the HSR is set if the card is present. Bit PRL in
the HSR is set if bit PRL has toggled.
During a session, the sequencer performs an automatic
emergency deactivation on the card in the event of card
take off, a short-circuit, a supply drop-out or overheating.
When the HSR register is updated and the INT0 line goes
LOW, the microcontroller will also be updated.
8.3.2
P
ROTECTIONS AND LIMITATIONS
TheTDA8030;TDA8031featuresthefollowingprotections
and limitations:
1.
I
CC
limited to 100 mA, deactivated when this limit is
reached
2.
Current to and from RST is limited to 20 mA,
deactivated when this limit is reached
3.
Deactivation when the temperature of the die exceeds
150
°
C
4.
Current to and from the I/O is limited to 10 mA
5.
Current to and from pin CLK is limited to 70 mA (not in
current reduction modes, when clock is stopped)
6.
ESD protection on all cards contacts + PRES at
6 kV (min.), thus no need of extra components for
protection against ESD flash caused by a charged
card being introduced in the slot
7.
Short-circuit between any cards contacts can last any
duration without any damage.
8.3.3
A
CTIVATION SEQUENCE
When the card is inactive, V
CC
, CLK, RST, I/O, C4 and C8
are LOW, with low-impedance with referenced to CGND.
The DC-to-DC converter is stopped.
When everything is in normal conditions (no error flag set),
the microcontroller will initiate an activation sequence of
the card.
After leaving the UART reset mode and then configuring
the necessary parameters for the UART, the START bit in
thePCR(t
0
)willbeactivated.Thefollowingsequencethen
occurs:
1.
The DC-to-DC converter is started (t
1
)
2.
V
CC
starts rising from 0 to 5 V or 3 or 1.8 V with a
controlled rise time of 0.17 V/
μ
s typically (t
2
)
3.
I/O, C4 and C8 rise to V
CC
(t
3
); integrated 10 k
pull-up resistors connected to V
CC
4.
Clock pulses are sent to the card and RST is enabled
(t
4
).
Afteranumberofclockpulsesthatcanbecountedwiththe
Time-Out Counter, the bit RSTIN may be set by software
and RST will rise to V
CC
.
The sequencer is clocked by
1
64
f
int
which leads to a time
interval of t = 25
μ
s typical.
Thus t
1
= 0 to
3
64
t, t
2
= t
1
+
5
2
t, t
3
= t
1
+
9
2
t
and t
4
= t
1
+ 5t.