NCN8024

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4

PIN FUNCTION AND DESCRIPTION

Pin #

Description

Type

Name

11

CRD_I/O

Input/

Output

This pin handles the connection to the serial I/O (C7) of the card connector. A bi−directional level

translator adapts the serial I/O signal between the card and the micro controller. An 11 kW (typical)

12

CRD_AUX2

Input/

Output

This pin handles the connection to the chip card’s serial auxiliary AUX2 I/O pin (C8). A bi−directional

level translator adapts the serial I/O signal between the card and the micro controller. An 11 kW

13

CRD_AUX1

Input/

Output

This pin handles the connection to the chip card’s serial auxiliary AUX1 I/O pin (C4). A bi−directional

level translator adapts the serial I/O signal between the card and the micro controller. An 11 kW

14

CRD_GND

GND

Card Ground

15

CRD_CLK

Output

This pin is connected to the CLOCK card connector’s pin (Chip card’s pin C3). The Clock signal

comes from the CLKIN input through clock dividers and level shifter.

16

CRD_RST

Output

This pin is connected to the chip card’s RESET pin (C2) through the card connector. A level

translator adapts the external Reset (RSTIN) signal to the smart card.

17

CRD_VCC

Power

This pin is connected to the smart card power supply pin. An internal DC/DC converter is

programmable using the pin 5V/3V to supply either 5 V or 3 V output voltage. An external distributed

and CRD_GND. This set of capacitor (if distributed) must be low ESR (< 100 mW).

18

PORADJ

Input

Power−on reset threshold adjustment input pin for changing the reset threshold with an external

resistor power divider. Recommended to be connected to ground when unused.

19

CMDVCC

Input

Command VCC pin. Activation sequence Enable/Disable pin (active Low). The activation sequence is

enabled by toggling CMDVCC High to Low and when a card is present.

20

RSTIN

Input

the smart card Reset pin through the internal level shifter which translates the level according to the

21

VDD

Power

This pin is connected to the system controller power supply. It configures the level shifter input

stage to accept the signals coming from the controller. A 0.1 mF capacitor shall be used to bypass

22

GND

GND

Ground

23

INT

Output

The interrupt request is activated LOW on this pin. This is enabled when a card is present and the

card presence is detected by CRD_PRES or CRD_PRES pins. Similarly an interrupt is generated

24

CLKIN

Input

Clock Input for External Clock

25

NC

Unconnected

26

I/Ouc

Input/

Output

This pin is connected to an external micro−controller. A bi−directional level translator adapts the

serial I/O signal between the smart card and the external controller. A built−in constant 11 kW

(typical) resistor provides a high impedance state.

27

AUX1uc

Input/

Output

This pin is connected to an external micro−controller. A bi−directional level translator adapts the

serial C4 signal between the smart card and the external controller. A built−in constant 11 kW

(typical) resistor provides a high impedance state.

28

AUX2uc

Input/

Output

This pin is connected to an external micro−controller. A bi−directional level translator adapts the

serial C8 signal between the smart card and the external controller. A built−in constant 11 kW

(typical) resistor provides a high impedance state.