LTC4556EUF Linear Technology, LTC4556EUF Datasheet
LTC4556EUF
Specifications of LTC4556EUF
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LTC4556EUF Summary of contents
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... The smart card pins can withstand greater than 10kV ESD in-situ with no additional components. The LTC4556 is available in a small, low profile (0.75mm), 4mm 4mm QFN package. , LTC and LT are registered trademarks of Linear Technology Corporation. *U.S. Patent No. 6,356,140 **U.S. Patent No. 6,411,531 180k ...
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... 3.3V BATT CPO = 3.075V 60mA, (Note 3) BATT CPO CC = 0mA, 10% to 90% ORDER PART NUMBER LTC4556EUF UF PART MARKING 4556 = 3.3V unless otherwise noted. MIN TYP MAX 2.7 5.5 250 400 0.5 1.75 1.7 5 0.2 1.5 8 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL Smart Card Supply V Output Voltage 5V Mode, 0 < Mode, 0 < I 1.8V Mode, 0 < Turn On-Time Undervoltage Detection ...
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LTC4556 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER CONDITIONS FAULT Low Level Output Voltage (V ) Sink Current = – 200 A OL Leakage Current V Serial Port Timing t D Valid to SCLK Setup DS IN ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS V Overcurrent Shutdown CC Threshold vs Temperature 140 V = 3.3V BATT 130 V = 1.8V, CPO = 4V CC 120 V = 5V, CPO = 5.5V CC 110 V = 3V, CPO ...
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LTC4556 CTIO S DV (Pin 1): Power. Reference voltage for the control CC logic. DATA (Pin 2): Input/Output. Microcontroller side data I/O pin. The DATA pin provides the bidirectional communica- tion path to the smart ...
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CTIO S UNDERV (Pin 20): Input. The UNDERV pin provides security by supplying a precision undervoltage threshold for external supply monitoring. An external resistive volt- age divider programs the desired undervoltage threshold. Once UNDERV falls ...
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LTC4556 U OPERATIO Serial Port The microcontroller compatible serial port provides all of the command and control inputs for the LTC4556 as well as the status of the smart card. Data on the D loaded on the rising edge of ...
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U OPERATIO Table 1. Serial Port Commands STATUS OUTPUT BIT COMMAND INPUT Options (See Table Card Select/Deselect 0 D3 Card Communications Card Electrical Fault D4 Options (See Table 4) Card ATR ...
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LTC4556 U OPERATIO Clock Channel As described in the section Serial Port, the LTC4556 supports both synchronous and asynchronous smart cards. When bits D5-D7 are set to 0s, the clock channel is in synchronous mode. In synchronous mode, the CLK ...
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U OPERATIO The built-in deactivation sequence can be executed via the serial port simply by setting the control bits D0 and The deactivation sequence is outlined below. 1. The RST pin is immediately brought low. 2. The ...
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LTC4556 U OPERATIO ATR faults are cleared by bringing the RST pin low via R An ATR fault will not automatically deactivate the smart card the application programmer’s responsibility to check the status register for ATR faults and ...
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U U APPLICATIO S I FOR ATIO 10kV ESD Protection All smart card pins (CLK, RST, I/O, C4, C8 and V withstand over 10kV of human body model ESD in-situ. In order to ensure proper ESD protection, careful board layout ...
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LTC4556 U U APPLICATIO S I FOR ATIO Interfacing to a Microcontroller The serial port of the LTC4556 can be connected directly to a 68HC11 style microcontroller’s serial port. The micro- controller should be configured as the master device and ...
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U U APPLICATIO S I FOR ATIO Asynchronous Card Detection Since the shift register is transparent when LD is held low the same as D7. Recall from Table 1 that D7 OUT indicates the status of the card ...
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LTC4556 U U APPLICATIO S I FOR ATIO A voltage source is still needed on both DV this configuration. Recall that DV CC ence level for all the control and smart card communica- tion pins. The voltage on V can ...
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U U APPLICATIO S I FOR ATIO INPUT POWER FAULT 4-WIRE COMMAND INTERFACE 4-WIRE CARD INTERFACE Figure 7. An LTC4556 and Two LTC1955s Daisy Chained Together – BATT 8 ...
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LTC4556 U U APPLICATIO S I FOR ATIO LTC4556 Fiugre 9. Additional Components for Improved Compliance Testing MAIN SUPPLY V = 1.23V (1 + R1/R2) TRIP R1 20 UNDERV LTC4556 R2 Figure 8. Setting the Undervoltage Trip ...
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... SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. U ...
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... PD4 44 (SS) PD5 24 (2MHz PB0 1 (IC3) PA0 28 PC0 46 PA7 29 PC1 V MODA EXTAL XTAL 10M 8.000MHz 27pF 27pF www.linear.com + 180k 262k 0.1 F 4.7 F Li-ION UNDERV V CC BATT 6 FAULT LTC4556EUF I RST CLK OUT 23 13 SCLK 0 PRES 5 ASYNC DATA 4 SYNC – CPO GND 9 11 ...