DS8005 Maxim, DS8005 Datasheet - Page 7

• Manufacturer Part Number: DS8005
• Description: The DS8005 dual smart card interface is a low-cost, dual analog front-end for an IC card reader interface that needs to communicate with two smart cards in a mutually exclusive fashion
• Manufacturer: Maxim

9, 14
PIN
1, 2
10
11
3
4
5
6
7
8
CLKDIV1,
CLKDIV2
PRESA
NAME
CGND
5V/3V
CLKB
RSTB
1_8V
V
V
I/OA
CCB
DDA
_______________________________________________________________________________________
Clock Divider. Determines the divided-down input clock frequency (presented at XTAL1 or from a
crystal at XTAL1 and XTAL2) on the CLK_ output pin. Dividers of 1, 2, 4, and 8 are available.
5V/3V Selection Pin. Allows selection of 5V or 3V for communication with an IC card. Logic-high
selects 5V operation; logic-low selects 3V operation. The 1_8V pin overrides the setting on this pin if
active. See Table 3 for a complete description of choosing card voltages.
1.8V Operation Selection. This active-high input puts the device into 1.8V smart card communication
mode. The selected interface (when activated) powers a card with a 1.8V supply and all I/O lines
operate at 1.8V.
Smart Card Supply Voltage, Interface B. Decouple to CGND (card ground) with 2 x 100nF or 100 +
200nF capacitors (ESR < 100m ).
Smart Card Interface Supply. 5V power supply for powering the card interface.
Smart Card Reset, Interface B. Card reset output from contact C2.
Smart Card Clock, Interface B. Card clock, contact C3.
Smart Card Ground
Interface A Card Presence Indicator. Active-high card presence input for the first card interface.
When the presence indicator becomes active, a debounce timeout begins. After 8ms (typ), the OFF
signal becomes active if the first card interface is selected (SEL_AB low), else the OFF2 signal
becomes active.
Smart Card Data-Line Output, Interface A. Card data communication line, contact C7. This pin is
only active if the first card interface is selected (SEL_AB low) and the interface has gone through an
activation sequence.
CLKDIV1
CLKDIV2
PRESA
PRESB
5V/3V
CGND
CGND
TOP VIEW
CLKB
RSTB
1_8V
V
V
I/OA
I/OB
CCB
DDA
10
11
12
13
14
1
2
3
4
5
6
7
8
9
DS8005
SO
Smart Card Interface
FUNCTION
28
27
26
25
24
23
22
21 V
20 RSTIN
19 CMDVCC
18 V
17 V
16 RSTA
15 CLKA
SEL_AB
OFF2
I/OIN
XTAL2
XTAL1
OFF
GND
DD
DDA2
CCA
Pin Configuration
Pin Description
7