tda8004t-c1 NXP Semiconductors, tda8004t-c1 Datasheet - Page 7

• Manufacturer Part Number: tda8004t-c1
• Description: Ic Card Interface
• Manufacturer: NXP Semiconductors

Philips Semiconductors
TDA8004T_4
Product data sheet
8.4 I/O circuitry
In the other cases, it is guaranteed between 45 % and 55 % of the period.
The crystal oscillator runs as soon as the IC is powered up. If the crystal oscillator is used,
or if the clock pulse on XTAL1 is permanent, then the clock pulse will be applied to the
card according to the timing diagram of the activation sequence (see
If the signal applied to XTAL1 is controlled by the system controller, then the clock pulse
will be applied to the card when the system controller will send it (after completion of the
activation sequence).
Table 4.
The three data lines I/O, AUX1 and AUX2 are identical.
The Idle state is realized by both lines (I/O and I/OUC) being pulled HIGH via a 10 k
resistor (I/O to V
I/O is referenced to V
The first side on which a falling edge occurs becomes the master. An anti-latch circuit
disables the detection of falling edges on the other line, which becomes a slave.
After a time delay t
turned on, thus transmitting the logic 0 present on the master side.
When the master side returns to logic 1, the P transistor on the slave side is turned on
during the time delay t
This active pull-up feature ensures fast LOW-to-HIGH transitions; it is able to deliver more
than 1 mA up to an output voltage of 0.9V
pull-up pulse, the output voltage only depends on the internal pull-up resistor and on the
load current (see
The maximum frequency on these lines is 1 MHz.
CLKDIV1
0
0
1
1
Clock circuitry definition
CC
Figure
d(edge)
and I/OUC to V
CC
Rev. 04 — 20 February 2006
d(edge)
and I/OUC to V
4).
(approximately 200 ns), the N transistor on the slave side is
and then both sides return to their Idle states.
CLKDIV2
0
1
1
0
DD
).
DD
CC
, thus allowing operation with V
on a 80 pF load. At the end of the active
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
CLK
1
1
1
f
XTAL
8
4
2
f
f
f
XTAL
XTAL
XTAL
TDA8004T
Figure
IC card interface
CC
5).
V
DD
.
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