Detailed Description

The DS8113 is an analog front-end for communicating

with 1.8V, 3V, and 5V smart cards. It is a dual input-

voltage device, requiring one supply to match that of a

host microcontroller and a separate +5V supply for

generating correct smart card supply voltages. The

DS8113 translates all communication lines to the cor-

rect voltage level and provides power for smart card

operation. It is a low-power device, consuming very lit-

tle current in active-mode operation (during a smart

card communication session), and is suitable for use in

battery-powered devices such as laptops and PDAs,

consuming only 10nA in stop mode. See Figure 1 for a

functional diagram.

Power Supply

The DS8113 is a dual-supply device. The supply pins

should be in the range of 2.7V to 6.0V, and is the sup-

ply for signals that interface with the host controller. It

should, therefore, be the same supply as used by the

host controller. All smart card contacts remain inactive

during power-on or power-off. The internal circuits are

and for the duration of the internal power-on reset

An internal regulator generates the 1.8V, 3V, or 5V card

separately by VDDA and PGND. VDDA should be con-

nected to a minimum 5.0V supply in order to provide

the correct supply voltage for 5V smart cards.

Voltage Supervisor

device inactive during power-on or power-off of the

The DS8113 card interface remains inactive no matter

card deactivation sequence if its card interface is

active.

Smart Card Interface

8

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TEMPERATURE

MONITOR

CARD VOLTAGE

GENERATOR

CLOCK

GENERATION

CONTROL

SEQUENCER

POWER-SUPPLY

SUPERVISOR

I/O TRANSCEIVER

VDD

GND

VDDA

PGND

CP1

CP2

VUP

VCC

XTAL1

XTAL2

CLKDIV1

CLKDIV2

1_8V

5V/3V

CMDVCC

RSTIN

CGND

RST

CLK

I/O

AUX1

AUX2

PRES

PRES

OFF

I/OIN

AUX1IN

AUX2IN

DS8113

Figure 1. Functional Diagram

VDD

ALARM

(INTERNAL SIGNAL)

POWER ON

POWER OFF

SUPPLY DROPOUT

Figure 2. Voltage Supervisor Behavior