TDA8035HN Datasheet, PDF (13/32 Pages) NXP Semiconductors – Smart card interface externally by a resistor bridge

NXP Semiconductors
TDA8035HN
Smart card interface
8.7 Activation sequence
The following sequence then occurs with crystal oscillator (see Figure 8):
T = 64 × Toscint(freq high)
1. CMDVCCN is pulled Low (t0)
2. Crystal oscillator start up time (t0).
3. The internal oscillator changes to its high frequency & DC/DC starts (t1 = t0 + 768 ×
Tosc_Low)
4. V_CC rises from 0 to selected Vcc value ( 5 V, 3 V, 1.8 V ) with a controlled slope
(t₂ = t₁ + 3T/2)
5. I/O, AUX1 and AUX2 are enabled (t₃ = t₁ + 10T) (They were pulled LOW until this
moment)
6. CLK is applied to the C3 contact (t₄ = t₃ + x) with 200 ns < x < 10 x 1/fXtal
7. RST is enabled (t₅ = t₁ + 13T).
Oscint
low frequency
CMDVCCN
Xtal1
VUP
VCC
IO
CLK
RST
≈ 3 ms
t0
t1
t2
Fig 8. Activation sequence at t3
high frequency
t3 t4
T/2
t5
001aan752
TDA8035HN
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 1.0 — 19 April 2011
© NXP B.V. 2011. All rights reserved.
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