LTC1756 Datasheet, PDF (1/12 Pages) Linear Technology – Smart Card Interface

FEATURES
s _{Fully ISO 7816-3 and EMV Compliant}
s _{Buck-Boost Charge Pump Generates 3V or 5V}
s _{2.7V to 5.5V Input Voltage Range}
s _3V↔ _{5V Signal Level Translator}
s _{> 10kV ESD on All Smart Card Pins}
s _{Dynamic Pull-Ups Deliver Fast Signal Rise Times}
s _{Soft Start Limits Inrush Current at Turn On}
s _{Very Low Operating Current: 75µA}
s _{Shutdown Current: < 2.5µA}
s _{Short-Circuit and Overtemperature Protected}
s _{Available in 16-Pin SSOP Package}
U
APPLICATIONS
s _{Handheld Payment Terminals}
s _{Pay Telephones}
s _ATMs
s _{Key Chain Readers}
s _{Smart Card Readers}
Final Electrical Specifications
LTC1756
Smart Card Interface
February 2000
DESCRIPTION
The LTC^®1756 universal Smart Card interface is fully
compliant with ISO 7816-3 and EMV specifications. It
provides the smallest and simplest interface circuit be-
tween a host microcontroller and general purpose Smart
Cards.
An internal charge pump DC/DC converter delivers regu-
lated 3V or 5V to the Smart Card, while an on-chip level
shifter allows a connection to a low voltage controller. All
Smart Card contacts are rated for 10kV ESD, eliminating
the need for external ESD protection devices.
Input voltage may range from 2.7V to 5.5V, allowing direct
connection to a battery. Automatic DC/DC converter soft
start mitigates start-up problems that may result when the
input power is provided by another regulator.
Battery life is maximized by 75µA operating current and
2µA shutdown current. The 16-pin SSOP package mini-
mizes PCB area for compact portable systems.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATION
SMART CARD
PRESENT SWITCH
N.O.
C3
10µF
GND _VCC
I/O
SMART CARD
RST
CLK
3.3V
C2
10µF
1
PRES
16
5V/3V
2
PWR
15
CARD
3
GND
14
READY
4
V_IN
C ^{– 13}
5
LTC1756
V_CC
C⁺
12
6
I/O
11
DATA
7
RST
10
RIN
8
CLK
9
CIN
C1
0.68µF
µCONTROLLER
1756 TA01
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.
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