ncn6000 ON Semiconductor, ncn6000 Datasheet - Page 32

• Manufacturer Part Number: ncn6000
• Description: Compact Smart Card Interface Ic
• Manufacturer: ON Semiconductor

Printed Circuit Board Layout
with high frequency clock, the printed circuit board must be
carefully designed to avoid the risk of uncontrolled
operation of the interface.
Figure 34 highlighting the ground technique.
Application Note
to support the NCN6000 applications is depicted in
Figure 35. This schematic diagram highlights the interface
between the microcontroller and the Smart Card, leaving
aside the peripherals used to control the MPU.
Conclusion
capacitor has been split into two 6.8 mF/10 V/X7R, one
being located as close as possible across pins 13 and 17 of
the NCN6000, the second one being located close by the
smart card physical connector. On the other hand, care has
Since the NCN6000 carries high speed currents together
A typical single−sided PCB layout is provided in
A partial schematic diagram of the demo board designed
From a practical stand point, the CRD_VCC output
Figure 34. Typical Single Sided Printed Circuit Board Layout
MPU
C4
CLK
RST
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2335 mis (60 mm)
NCN6000
GROUND
32
parts being located on the Component side. Connector J3
makes reference to the microcontroller used by the final
application. Of course, the connector is not necessary and
standard copper tracks might be used to connect the MPU to
the NCN6000 interface chip.
been observed to minimize the cross coupling between the
clock signals (both Input and CRD_CLK) and the other
signals presents on the board.
program the NCN6000, together with the code handling the
T0 operation. Provisions are made to provide a
communication link with an external computer by using the
RS232 standard port.
a common data bus as depicted in Figure 36. In this example,
two interfaces are connected to a single MPU, the CS pins
being controlled by two different signals.
SMARTCARD ISO CONTACTS
The card socket uses a low cost ISO only version, all the
The microcontroller holds the software necessary to
Due to the Chip Select signal, several NCN6000 can share
C8
I/O
V
GND
PP