Features
•
Smart Card Interface
– Compliance with ISO 7816, EMV2000, GIE-CB, GSM and WHQL Standards
Card Clock Stop High or Low for Card Power-down Modes
Support Synchronous Cards with C4 and C8 Contacts
Card Detection and Automatic de-activation Sequence
Programmable Activation Sequence
– Direct Connection to the Smart Card
Logic Level Shifters
Short Circuit Current Limitation (see electrical characteristics)
8kV+ ESD Protection (MIL/STD 883 Class 3)
– Programmable Voltage
5V ±5% at 65 mA (Class A)
3V ±0.2V at 65 mA (Class B)
1.8V ±0.14V at 40 mA
– Low Ripple Noise: < 200 mV
Versatile Host Interface
– ICAM (Conditional Access) Compatible
– Two Wire Interface (TWI) Link
Programmable Address Allow up to 8 Devices
– Programmable Interrupt Output
– Automatic Level Shifter (1.6V to V
CC
)
Reset Output Includes
– Power-On Reset (POR)
– Power-Fail Detector (PFD)
High-efficiency Step-up Converter: 80 to 98% Efficiency
Extended Voltage Operation: 3V to 5.5V
Low Power Consumption
– 180 mA Maximum In-rush Current
– 30
μA
Typical Power-down Current (without Smart Card)
4 to 48 MHz Clock Input, 7 MHz Min for Step-up Converter (for AT83C24)
18 to 48MHz Clock input (for AT83C24NDS)
Industrial Temperature Range: -40 to +85°C
Packages: SO28 and QFN28
•
Smart Card
Reader
Interface with
Power
Management
AT83C24B
AT83C24NDS
•
•
•
•
•
•
•
•
Description
The AT83C24 is a smart card reader interface IC for smart card reader/writer applica-
tions such as EFT/POS terminals and set top boxes. It enables the management of
any type of smart card from any kind of host. Up to 8 AT83C24 can be connected in
parallel using the programmable TWI address.
Its high efficiency DC/DC converter, low quiescent current in standby mode makes it
particularly suited to low power and portable applications. The reduced bill of material
allows reducing significantly the system cost. A sophisticated protection system guar-
antees timely and controlled shutdown upon error conditions.
The AT83C24NDS is a dedicated version approved by NDS for use with NDS Video-
Guard conditional access software in set-top boxes. All AT83C24 datasheet is
applicable to AT83C24NDS. The main differences between AT83C24 and
AT83C24NDS are listed below:
1/ CLASS A card supplied with CVCC = 4.75 to 5.25V for AT83C24NDS,
CLASS A card supplied with CVCC = 4.6 to 5.25V for AT83C24
2/ 18MHz minimum on input clock for AT83C24NDS
3/ Up to 10µF for capacitor connected on CVCC pin for AT83C24,
3.3µF mandatory for AT83C24NDS
4234F–SCR–10/05
Acronyms
TWI: Two-wire Interface
POR: Power On Reset
PFD: Power Fail Detect
ART: Automatic Reset Transition
ATR: Answer To Reset
MSB: Most Significant Bit
LSB: Least Significant bit
SCIB: Smart Card Interface Bus
Block Diagram
VCC
VSS
LI
CVSS
DVCC
EVCC
RESET
Voltage
supervisor
POR/PFD
CVCC
DC/DC
Converter
CVCCIN
PRES/ INT
A2/CK, A1/RST, A0/3V, CMDVCC
SCL
SDA
TWI
Controller
Main
Control
& Logic Unit
Timer
16 Bits
Clocks Controller
CLK
Analog
Drivers
CPRES
CRST
CIO, CC4, CC8
CCLK
I/O, C4, C8
2
AT83C24
4234F–SCR–10/05
AT83C24
Pin Description
Pinouts (Top View)
28-pin SOIC Pinout
QFN28 pinout
PRES/INT
CLK
2
3
4
5
6
7
8
9
10
11
12
13
14
RESET
CMDVCC
VSS
27
26
25
24
23
22
21
20
19
18
17
16
15
PRES/INT
C4
I/O
EVCC
A2/CK
A1/RST
A0 /3V
SCL
SDA
CMDVCC
VSS
28 27 26 25 24 23 22
1
21
20
2
3
4
5
6
7
8
QFN 28
TOP VIEW
19
18
17
16
C8
C8
DVCC
1
28
DVCC
CLK
RESET
I/O
EVCC
A2 /CK
A1 /RST
A0 /3V
SCL
VCC
CVSS
LI
CVCC
CVCCin
CRST
CCLK
V
CC
LI
CVSS
NC
CIO
CC8
CPRES
CVCC
CVCCin
SDA
15
NC
9 10 11 12 13 14
CRST
CCLK
CPRES
NC
CC4
C4
CC8
NC
CC4
Note:
1. NC = Not Connected
2. SOIC and QFN packages are available for
AT83C24 and for AT83C24NDS
Signals
Table 1.
Ports Description
Pad Name
Pad Internal
Power Supply
ESD
Limits
Pad
Type
Description
Microcontroller Interface Function:
TWI bus slave address selection input.
A2/CK-
A1/RST-
A0/3V
EVCC
3 kV
I
A2/CK and A1/RST pins are respectively connected to CCLK and CRST signals in
“transparent mode” (see page 17 ).
A0/3V is used for hardware activation to select CVCC voltage (3V or 5V).
The slave address of the device is based on the value present on A2, A1, A0 on the
rising edge of RESET pin (see Table 2). In fact, the address is taken internally at the 11th
CLK rising edge.
Microcontroller Interface Function:
Depending on IT_SEL value (see CONFIG4 register),
PRES/INT
EVCC
3 kV
O
open-
drain
PRES/INT outputs card presence status or interruptions (page 9)
An internal Pull-up (typ 330kΩ,see Table 18)to EVCC can be activated in the pad if
necessary using INT_PULLUP bit (CONFIG4 register).
Remark: during power up and before registers configuration, the PRES/INT signal must
be ignored.
Microcontroller Interface Function:
•
•
I/O
RESET
VCC
3 kV
open-
drain
•
•
Power-on reset
A low level on this pin keeps the AT83C24 under reset even if applied on power-on.
It also resets the AT83C24 if applied when the AT83C24 is running (see Power
monitoring §).
Asserting RESET when the chip is in Shut-down mode returns the chip to normal
operation.
AT83C24 is driving the Reset pin Low on power-on-reset or if power fail on V
CC
or
DVCC (see POWERMON bit in CONFIG4 register), this can be used to reset or
interrupt other devices. After reset, AT83C24 needs to be reconfigured before
starting a new card session.
CIO
3
4234F–SCR–10/05
Table 1.
Ports Description (Continued)
Pad Name
Pad Internal
Power Supply
ESD
Limits
3 kV
Pad
Type
I/O
open-
drain
I/O
open-
drain
Description
Microcontroller Interface Function
TWI serial data
SDA
VCC
SCL
VCC
3 kV
Microcontroller Interface Function
TWI serial clock
Microcontroller Interface Function
I/O
EVCC
3 kV
Copy of CIO pin and high level reference for EVCC.
I/O
An external pull up to EVCC is needed on IO pin.
I/O is the reference level for EVCC if EVCC is connected to a capacitor.
This feature is unused if EVCC is connected to VCC.
C4
EVCC
3 kV
I/O
Microcontroller Interface Function
(pull-up) Copy of Card CC4.
3 kV
I/O
Microcontroller Interface Function
C8
EVCC
(pull-up) Copy of Card CC8.
3 kV
I
I/O
Microcontroller Interface Function
Master Clock
Smart card interface function
CLK
EVCC
CIO
CVCC
8 kV+
(pull-up) Card I/O
I/O
Smart card interface function
CC4
CVCC
8 kV+
(pull-up) Card C4
I/O
Smart card interface function
CC8
CVCC
8 kV+
(pull-up) Card C8
Smart card interface function
CPRES
VCC
8 kV+
I
Card presence
(pull-up) An internal Pull-up to VCC can be activated in the pad if necessary using PULLUP bit
(CONFIG1 register).
O
Smart card interface function
Card clock
Smart card interface function
Card reset
Microcontroller Interface Function:
Activation/Shutdown of the smart card Interface.
Supply Voltage
V
CC
is used to power the internal voltage regulators and I/O buffers.
DC/DC Input
LI
must be
tied to VCC pin through an external coil (typically 4.7
μH)
and provides the
current for the charge pump of the DC/DC converter.
It may be directly connected to VCC if the step-up converter is not used (see STEPREG
bit in CONFIG4 register and see minimum VCC values in Table 20 (class A) and
Table 21 (class B)).
CCLK
CVCC
8 kV+
CRST
CVCC
8 kV+
O
I
(pull-up)
CMDVCC
EVCC
3 kV+
VCC
3 kV+
PWR
LI
3 kV+
PWR
4
AT83C24
4234F–SCR–10/05
AT83C24
Table 1.
Ports Description (Continued)
Pad Name
Pad Internal
Power Supply
ESD
Limits
Pad
Type
Description
Card Supply Voltage
CVCC
8 kV+
PWR
CVCC is the programmable voltage output for the Card interface.
It must be connected to external decoupling capacitors (see page 34 and page 36).
CVCCin
8 kV+
PWR
Card Supply Voltage
This pin must be connected to CVCC.
Digital Supply Voltage
DVCC
3 kV+
PWR
Is internally generated and used to supply the digital core.
This pin has to be connected to an external capacitor of 100 nF and should not be
connected to other devices.
Extra Supply Voltage (Microcontroller power supply)
EVCC is used to supply the internal level shifters of host interface pins.
EVCC
3 kV+
PWR
EVCC voltage can be supplied from the external EVCC pin connected to the host power
supply.
If EVCC cannot be connected to the host power supply, it must be tied to an external
capacitor. EVCC voltage can be generated internally by an automatic follow up of the
logic high level on the I/O pin. In this configuration, connect a 100 nF + 100kOhms in
parallel between EVCC pin and VSS pin.
CVSS
VSS
8 kV+
GND
GND
DC/DC Ground
CVSS is used to sink high shunt currents from the external coil.
Ground
Note:
ESD Test conditions: 3 positive and 3 negative pulses on each pin versus GND. Pulses generated
according to Mil/STD 883 Class3. Recommended capacitors soldered on CVCC and VCC pins.
5
4234F–SCR–10/05
