ncn6004a ON Semiconductor, ncn6004a Datasheet - Page 32

• Manufacturer Part Number: ncn6004a
• Description: Dual Sam/sim Interface Integrated Circuit
• Manufacturer: ON Semiconductor

MUX_MODE = Low " PARALLEL OPERATION
are routed straightforward to their appropriate outputs. The
two I/O lines can operate simultaneously, depending upon
the mP capabilities, regardless of the CARD_SEL signal
logic level.
be connected or not as defined by the EN_RPU signal.
MUX_MODE = High " MULTIPLEXED OPERATION
used to handle data for CARD_A and CARD_B. The signal
CARD_SEL
The bi−directional switch Q9 is OFF and the I/O signals
The pull up resistors, on the mP side of each I/O line, can
The bi−directional switch Q9 is ON and the I/O_A pin is
PWR_ON
EN_RPU
MUX_MODE
ANLG_VCC
I/O_B
PGM
CS
I/O_A
19
45
6
8
7
5
42
44
9
Figure 33. Dual Bi−directional I/O Line Level Shifter and Multiplex
Q9
Q11
Q10
R3
R1
CONTROL LOGIC
& Level Shifter
CONTROL LOGIC
& Level Shifter
Q6
http://onsemi.com
Q1
NCN6004A
BI−DIRECTIONNAL DATA TRANSFERT
BI−DIRECTIONNAL DATA TRANSFERT
32
is routed to the appropriate card by means of the
CARD_SEL logic signal. In this mode, the I/O_B pin 19
must be left open since the internal data signal will be
present on this pin.
resistor R1 is automatically disconnected to maintain the I/O
line impedance to 20 kW (typical), what ever be the
EN_RPU logic level. This feature makes sure the current
flowing trough the external card is limited to 500 mA during
a low level state.
Moreover, since R1 and R3 are in parallel, the pull up
CRD_VCC_B
ANLG_VCC
Q7
CRD_VCC_A
ANLG_VCC
Q3
Q8
Q4
GND
GND
Q5
Q10
Q11
Q2
R2
R4
29
24
32
37
CRD_VCC_A
CRD_I/O_A
CRD_VCC_B
CRD_I/O_B