tda8034at NXP Semiconductors, tda8034at Datasheet - Page 8

• Manufacturer Part Number: tda8034at
• Description: Smart Card Interface
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDA8034T_TDA8034AT_1
Product data sheet
8.5 Shutdown mode
8.6 Activation sequence
After a power-on reset, if pin CMDVCCN is HIGH, the circuit enters the Shutdown mode,
ensuring only the minimum number of circuits are active while the TDA8034T/TDA8034AT
waits for the microcontroller to start a session.
The following device activation sequence is applied when using an external clock; see
Figure
Calculation of the time delays is as follows:
Remark: The value of period T is 64 times the period interval of the internal oscillator at
high frequency (
1. Pin CMDVCCN is pulled LOW (t0).
2. The internal oscillator is triggered (t0).
3. The internal oscillator changes to high frequency (t1).
4. V
5. Pin I/O is driven HIGH (t3).
6. The clock on pin CLK is applied to the C3 contact (t4).
7. Pin RST is enabled (t5).
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all card contacts are inactive. The impedance between the contacts and GND is
approximately 200 .
pin I/OUC is high-impedance using the 11 k pull-up resistor connected to V
the voltage generators are stopped
the voltage supervisor is active
the internal oscillator runs at its lowest frequency (f
t1 = t0 + 384
t2 = t1
t3 = t1 + 17T / 2
t4 = driven by host controller; > t3 and < t5
t5 = t1 + 23T / 2
CC
6:
rises from either 0 V to 3 V or 0 V to 5 V on a controlled slope (t2).
1
fosc(int)high
1
fosc(int)low
Rev. 01 — 5 February 2010
); t3 is called t
TDA8034T; TDA8034AT
d(start)
and t5 is called t
osc(int)low
)
d(end)
Smart card interface
.
© NXP B.V. 2010. All rights reserved.
DD(INTF)
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