ST8034HC datasheet(23/31 Pages) STMICROELECTRONICS

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ST8034HN, ST8034HC

Functional description

6.6

Deep shutdown mode

When the smartcard reader is inactive, the ST8034HN and ST8034HC enter a deep

shutdown mode if the CMDVCC pin is forced high and the VCC_SEL1 and VCC_SEL2 pins

are low. In deep shutdown mode, all circuits are disabled and the OFF pin follows the status

of the PRES pin. Changing the status of either CMDVCC, VCC_SEL1 or VCC_SEL2 exits

the deep shutdown mode, see Figure 9.

Figure 9. Shutdown and deep shutdown mode activation and deactivation

6.7

Activation sequence

The following device activation sequence is applied when using an external clock, also see

Figure 10:

CMDVCC is pulled low (t0).

The internal oscillator is triggered (t0).

The internal oscillator changes to high frequency (t1).

VCC rises from 0 V to 1.8 V or to 3 V or to 5 V on a controlled slope (t2).

I/O, AUX1, AUX2 are driven high (t3).

The clock on the CLK output is applied to the C3 contact (t4).

RST is enabled (t5).

ST8034HC Datenblatt(PDF) 23 Page - STMicroelectronics