LTC1955 Dual Smart Card Interface with Serial Control Fea T Descrip T n Compatible with ISO7816-3 and EMV Electrical The LTC 1955 provides all necessary supervisory and Specifications power control functions for two smart cards, two S.A.M. n Power Management and Control for Two Smart Cards cards or a combination of S.A.M. and smart cards. It n Control/Status Serial Port May Be Daisychained for provides a charge pump for battery-powered applications Multicard Applications as well as all necessary level shifting circuitry. n Automatic Shutdown on Electrical Faults The card voltages can be independently set to 1.8V, 3V or n Buck/Boost Charge Pump Generates 5V, 3V or 1.8V 5V. Both card interfaces include a card detection channel Outputs (Smart Card Classes A, B and C) with automatic debounce circuitry. To reduce wiring costs, n Independent 5V/3V/1.8V Level Control for Both Cards the LTC1955 interfaces to a microcontroller via a simple n Automatic Level Translation 4-wire serial interface. Multiple devices may be connected n Supervisory Functions Prevent Smart Card Faults in daisychain fashion so that the number of wires to the n Low Operating Current: 250A Typical card socket board is independent of the number of sockets. n Ultralow Shutdown Current Status data is returned over the same interface. n >10kV ESD on Smart Card Pins n Extensive security features ensure proper deactivation Small 32-Lead 5mm 5mm QFN Package sequencing in the event of a supply fault or a smart card a T electrical fault. The smart card pins can withstand greater than 10kV ESD in-situ with no additional components. n Handheld Payment Terminals n Pay Telephones The LTC1955 is available in a low profile (0.75mm) 5mm n ATM Machines 5mm QFN package. n POS Terminals L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Computer Keyboards Protected by U.S. Patents, including 6356140, 6411531. n Multiple S.A.M. Sockets 240k 180k Typical a T 23 CARD UNDERV 1 2 DETECT DV PRES A CC 12,13 V BATT INPUT POWER 0.1F 4.7F LTC1955 Deactivation Sequence 3 9, 10 C8A GND 4 C4A 5 24 I/O A RST A FAULT 6 5V/DIV RST A 27 7 D CLK A IN 28 8 SMART CARD CLK A 4-WIRE D V OUT CCA 5V/DIV 26 COMMAND SCLK 1F INTERFACE 25 21 LD PRES B I/O A 5V/DIV V CCA 29 20 DATA I/O B 5V/DIV 30 19 4-WIRE 1955 TA01a R RST B IN 10s/DIV CARD 32 18 SYNC CLK B INTERFACE VENDOR CARD 31 17 ASYNC V CCB 22 NC/NO 1F + C C CPO 1955 TA01b 14 11 15 1F 4.7F 1955fd 1 For more information www.linear.com/LTC1955 ion pplica ions pplica ion uresLTC1955 a Te Maxi Mu M r a T p in c F T (Note 1) TOP VIEW V , DV , CPO, FAULT, BATT CC UNDERV to GND ....................................... 0.3V to 6.0V PRES A/PRES B, DATA, R , SYNC, ASYNC, IN LD, D , SCLK to GND .................0.3V to (DV + 0.3V) IN CC 32 31 30 29 28 27 26 25 I/O A ............................................ 0.3V to (V + 0.3V) DV 1 24 FAULT CCA CC PRES A 2 23 UNDERV I/O B ............................................ 0.3V to (V + 0.3V) CCB C8A NC/NO 3 22 I /IV .............................................................80mA VCCA CCB C4A 4 21 PRES B 33 V /V Short-Circuit Duration ..................... Indefinite CCA CCB SGND I/O A 5 20 I/O B Operating Temperature Range (Note 4).... 40C to 85C RST A 6 19 RST B Junction Temperature ........................................... 125C CLK A 7 18 CLK B Storage Temperature Range ................... 65C to 125C V 8 17 V CCA CCB 9 10 11 12 13 14 15 16 UH PACKAGE 32-LEAD (5mm 5mm) PLASTIC QFN T = 125C, = 34C/W JMAX JA EXPOSED PAD (PIN 33) IS SGND, MUST BE SOLDERED TO PCB Der in F Ma T LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC1955EUH PBF LTC1955EUH TRPBF 1955 40C to 85C 32-Lead (5mm 5mm) Plastic QFN LTC1955IUH PBF LTC1955IUH TRPBF 1955 40C to 85C 32-Lead (5mm 5mm) Plastic QFN LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC1955EUH LTC1955EUH TR 1955 32-Lead (5mm 5mm) Plastic QFN 40C to 85C LTC1955IUH LTC1955IUH TR 1955 32-Lead (5mm 5mm) Plastic QFN 40C to 85C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: