tda8020hl-c2 NXP Semiconductors, tda8020hl-c2 Datasheet - Page 7

• Manufacturer Part Number: tda8020hl-c2
• Description: Dual Smart Card Interface
• Manufacturer: NXP Semiconductors

Philips Semiconductors
FUNCTIONAL DESCRIPTION
Throughout this specification, it is assumed that the reader
is familiar with ISO 7816 terminology.
Supply
The TDA8020HL operates with a supply voltage from
2.7 to 6.5 V. An integrated voltage supervisor ensures that
no spike appears on cards contacts during power-on or off.
The supervisor also initializes the device, and forces an
automatic emergency deactivation of the contacts in the
event of a supply drop-out.
As long as the supply voltage is below the threshold
voltage V
the supply voltage reaches V
charged with a small current source of approximately 2 A.
When the voltage on C
supervisor is no longer active. As long as the supervisor is
active (pin IRQ is LOW), bit SUPL in the status register is
set. When pin IRQ goes HIGH the voltage supervisor
becomes inactive (see Fig.3).
2003 Nov 06
handbook, full pagewidth
Dual IC card interface
th1
, the capacitor C
V th1
V CDEL
V DD
IRQ
V hys1
V th2
V th1
DEL
reaches V
DEL
th1
remains uncharged. When
BUS NOT RESPONDING
and V
th2
hys1
, then the
, then C
t w
Fig.3 Voltage supervisor.
DEL
is
BUS OK
7
status read
after event
Separate supply pins are used for the DC-to-DC converter,
allowing specific decoupling for counteracting the noise
the switching transistors may induce on the supply.
A specific reference supply voltage, V
interface signals CLKIN1, CLKIN2, I/O1uC, I/O2uC,
SAD0, SAD1, SCL, SDA and IRQ, which can be lower
than V
a low voltage supplied device.
Pins SCL, SDA and IRQ are open-drain outputs, and may
be externally pulled up to a voltage higher than V
DD
RESPONDING
(minimum 1.5 V), thus allowing direct control with
BUS NOT
t w
BUS OK
RESPONDING
BUS NOT
TDA8020HL
Product specification
DDI
FCE835
, is used for the
DD
.