DESCRIPTION
●The ST8024 is a complete low cost analog interface for asynchronous 3V and 5V smart cards. It can be placed between the card and the microcontroller with few external components to perform all supply protection and control functions. ST8024 is a direct replacement of ST8004.
●■ IC CARD INTERFACE
●■ 3 OR 5 V SUPPLY FOR THE IC (VDDAND GND)
●■THREE SPECIFICALLY PROTECTED HALF-DUPLEX BI-DIRECTIONAL BUFFERED I/O LINES TO CARD CONTACTS C4, C7 AND C8
●■ DC/DC CONVERTER FOR VCC GENERATION SEPARATELY POWERED FROM A 5 V ± 20% SUPPLY (VDDPAND PGND)
●■ 3 OR 5 V ±5% REGULATED CARD SUPPLY VOLTAGE (VCC) WITH APPROPRIATE DECOUPLING HAS THE FOLLOWING
●CAPABILITIES:
● – ICC< 80 mA at VDDP= 4 to 6.5 V
● – HANDLES CURRENT SPIKES OF 40 nAs UP TO 20MHz
● – CONTROLS RISE AND FALL TIMES
● – FILTERED OVERLOAD DETECTION AT APPROXIMATELY 120 mA
●■ THERMAL AND SHORT-CIRCUIT PROTECTION ON ALL CARD CONTACTS
●■ AUTOMATIC ACTIVATION AND DEACTIVATION SEQUENCES; INITIATED BY SOFTWARE OR BY HARDWARE IN THE EVENT OF A SHORT-CIRCUIT, CARD TAKE-OFF, OVERHEATING, VDDOR VDDP DROP-OUT
●■ ENHANCED ESD PROTECTION ON CARD SIDE (>6 kV)
●■ 26 MHz INTEGRATED CRYSTAL OSCILLATOR
●■ CLOCK GENERATION FOR CARDS UP TO 20 MHz (DIVIDED BY 1, 2, 4 OR 8 THROUGH CLKDIV1 AND CLKDIV2 SIGNALS) WITH SYNCHRONOUS FREQUENCY CHANGES
●■ NON-INVERTED CONTROL OF RST VIA PIN RSTIN
●■ ISO 7816, GSM11.11 AND EMV (PAYMENT SYSTEMS) COMPATIBILITY
●■ SUPPLY SUPERVISOR FOR SPIKE-KILLING DURING POWER-ON AND POWER-OFF AND POWER-ON RESET (THRESHOLD
●FIXED INTERNALLY OR EXTERNALLY BY A RESISTOR BRIDGE)
●■ BUILT-IN DEBOUNCE ON CARD PRESENCE CONTACTS
●■ ONE MULTIPLEXED STATUS SIGNAL OFF
