Introduction to Smart Cards
A
smart card is a plastic card (dimension 85.6mm x 53.98mm x 0.76mm) that
contains an embedded computer chip (either a memory
or microprocessor
type) that stores and transacts data. This data is usually associated with
either value, information, or both and is stored and processed within the
card's chip. The card data is transacted via a reader that is part of a
computing system.
Figure
1. Smart Cards
Smart
cards are defined according to how the card data is read/written and the type
of chip implanted within the card and its capabilities. Figure 2 shows
classification smart cards according to chip cards implanted.
Figure 2.
Classifications smart cards
The ISO
Standard (7816-2) defined eight contacts but only 6 are actually used to
communicate with the outside World. Figure 3 shows contact card pin
configurations.
Figure 3. The Contact Card Pins Configuration.
Each pin is assigned to
·
C1: supply power input (VCC).
There are 3 three classes of operating conditions, based on the nominal
supply voltage provided to the card.
§ 5
V for class A.
§ 3
V for class B. (our card
is of type B)
§ 1,8
V for class C.
·
C2: reset signal input (RST).
·
C3: clock signal input (CLK).
This
contact is used to provide the card with clock signal. The actual value of the
frequency of the clock signal is denoted f. The minimum value shall be 1
MHz.
· C5: ground (GND, reference voltage).
·
C6: standard or proprietary use (VPP).
This
contact is available for either standard or proprietary use, as input and/or
output.
·
C7: input/output for serial data
(I/O).
This
contact is used as input (reception mode) or output (transmission mode). The
information exchange uses two states of the electrical circuit as follows:
A.
State H if the card and the interface
device are in reception mode or if the transmitter imposes this state.
B.
State L if the transmitter imposes
this state.
Systems
that are enhanced with smart cards are in use today throughout several key
applications, including health care, banking, entertainment, and transportation.
All applications can benefit from the added features and security that smart
cards provide.