TDA8034T Datasheet, PDF (9/29 Pages) NXP Semiconductors – Smart card interface

NXP Semiconductors
TDA8034T; TDA8034AT
Smart card interface
CMDVCCN
XTAL
V_CC
I/O
CLK
RSTIN
> 200 ns
RST
I/OUC
OSCINT
low frequency
t0 t1 = t2
t4
t_d(start)
OSCINT = internal oscillator.
Fig 6. Activation sequence at t3
high frequency
t_d(end) = t_act
ATR
001aai966
8.7 Deactivation sequence
When a session ends, the microcontroller sets pin CMDVCCN HIGH. The
TDA8034T/TDA8034AT then executes an automatic deactivation sequence by counting
the sequencer back to the inactive state (see Figure 7) as follows:
1. Pin RST is pulled LOW (t11).
2. The clock is stopped, pin CLK is LOW (t12).
3. Pin I/O is pulled LOW (t13).
4. V_CC falls to 0 V (t14). The deactivation sequence is completed when V_CC reaches its
inactive state.
5. V_CC < 0.4 V (t_deac)
6. All card contacts become low-impedance to GND. However, pin I/OUC remains pulled
up to V_DD using the 11 kΩ resistor.
7. The internal oscillator returns to its low frequency mode.
Calculation of the time delays is as follows:
• t11 = t10 + 3T / 64
• t12 = t11 + T / 2
• t13 = t11 + T
• t14 = t11 + 3T / 2
• t_deac = t11 + 3T / 2 + V_CC fall time
TDA8034T_TDA8034AT
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2.0. — 12 November 2010
© NXP B.V. 2010. All rights reserved.
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