AS3953A
14443 High Speed Passive Tag
Interface
General Description
The AS3953A NFC interface IC (NFiC) delivers low cost, ultra low
power NFC Forum functionality to multiple different
applications. The AS3953A is a analog front-end with integrated
14443A data framing and SPI interface. It is designed to create
a fast data link between an ISO 14443A reader device (PCD) and
a microcontroller. The AS3953A is
passively powered
meaning
that it can be supplied from the PCD magnetic field, eliminating
the need of a continual external supply. This makes the
AS3953A perfect for wireless communication to a low-power
battery powered device.
The AS3953A is used with an appropriate antenna coil
connected to the terminals LC1 and LC2, and behaves as a
normal passive ISO 144443A tag (PICC). After the anti-collision
protocol is passed, the PCD sends a
Wake-Up
command, which
wakes up the microcontroller by sending an interrupt. From this
point onwards, the AS3953A serves as a data link between the
microcontroller and the PCD. AS3953A can also operate as
NFCIP-1 target at 106 kbit/s.
The AS3953A includes an onboard EEPROM that can be
accessed either from the PCD or from the microcontroller via
the SPI interface. This built-in flexibility makes it ideal for two
types of applications:
•
Where personalization data is programmed by the PCD
(even in case the SPI side is not powered) and it is later
read by microcontroller through SPI interface.
•
Where log data is stored periodically by the
microcontroller and can then be read by the PCD even
when the microcontroller is not powered.
A regulated power supply voltage extracted from the PCD field
is also available on a pin and can be used as power supply for
external circuitry. For example, an external microcontroller and
a sensor could be powered from the PCD field combined with
pass through data rates up to 848kbit/s, which means the
AS3953A is ideal for contactless passive programming of MCU
systems. The AS3953A can also operate as a stand-alone ISO
14443A tag.
The AS3953A supports ISO 14443A up to Level-4, meaning a
contactless smart card or an NFC forum compatible tag (Tag
Type 4) can be built. Having a NFC Forum compatible tag
interface allows the AS3953A to be used in an application where
a standard NFC enabled phone is used as a PCD.
Ordering Information
and
Content Guide
appear at end of
datasheet.
ams Datasheet
[v1-04] 2015-Dec-28
Page 1
Document Feedback
AS3953A −
General Description
Key Benefits & Features
The benefits and features of AS3953A, 14443 High Speed
Passive Tag Interface are listed below:
Figure 1:
Added Value of Using AS3953A
Benefits
•
NFC Forum compliance for full
interoperability
•
ECMA-340 / ISO/IEC_18092 compliance
•
Internal user memory for standalone
application
•
Allows zero-power standby
•
Enables long battery life time, or
battery-less designs
•
Allows supply of external circuitry
•
Data rate transmission up to the
maximum allowed by ISO 14443A
compliance
•
Easy and fast antenna design and
impedance matching
•
Guarantees no reset during reader (PCD)
modulation
•
Design flexibility, easy integration.
•
Fits requirements for various embedded
applications and manage of external
microcontroller
•
Fits supply requirements for various
applications, including industrial
•
Flexibility for wide range of applications
•
Small outline, compatibility to common
inlay and card manufacturing lines,
surface-mount assembly
Features
•
ISO 14443A compliant to Level-4
•
NFCIP-1 target at 106 kbit/s
•
1k bit EEPROM (108 bytes of user memory)
•
Configurable wake-up interrupt (after tag is selected or
using proprietary command)
•
Powered from external magnetic field with the possibility to
draw up to 5mA
•
User configurable regulated voltage extracted from external
magnetic field
•
Bit rates from 106 kbit/s till 848 kbit/s
•
7 byte UID
•
Integrated resonant capacitor
•
Integrated buffer capacitor
•
4-wire Serial Peripheral Interface (SPI) with 32 byte FIFO
•
Wide SPI power supply range (1.65V to 3.6V)
•
Wide temperature range: -40ºC to 85ºC
•
Available as WLCSP 10-bumps, 10-pin MLPD (3x3mm) and
Gold bumped dies
Page 2
Document Feedback
ams Datasheet
[v1-04] 2015-Dec-28
AS3953A −
General Description
Applications
The device is ideal for applications like
•
Passive wake-up
•
Multipurpose HF interface to a controller
•
Low power or passive programming
•
Ultra low power data logger
•
RFID programmable configuration EEPROM
•
ISO 14443A smart card
•
NFC Forum Tag Type 4
•
Bluetooth and Wi-Fi pairing
Block Diagram
The functional blocks of this device are shown below:
Figure 2:
AS3953A Block Diagram
VP_REG
VP_INT
Power
Manager
VDD
LC1
AFE
LC2
POR
Logic
EEPROM
AS3953A
VP_SPI
IRQ
Level
Shifters
SPI
VSS
ams Datasheet
[v1-04] 2015-Dec-28
Page 3
Document Feedback
AS3953A −
Pin Assignment
Pin Assignment
Figure 3:
Pin Diagram (Top View)
GND
VP_SPI
VP_REG
LC1
LC2
VSS
1
2
3
4
5
10
IRQ
MISO
MOSI
SCLK
/SS
AS3953A
MLPD
(Top view)
9
8
7
6
/SS
A1
IRQ
MOSI
A2
MISO
A3
A4
SCLK
B1
VP_REG
B4
LC2
B2
LC1
B3
VSS
C1
VP_SPI
C4
AS3953 A
WL-CSP
(Top view)
10
9
8
7
6
MOSI
MISO
SCLK
IRQ
/SS
AS3953A
TEST
Gold bumped die
(Bottom view)
VP_REG
VP_SPI
0
LC1
LC2
1
2
3
4
Page 4
Document Feedback
VSS
5
ams Datasheet
[v1-04] 2015-Dec-28
AS3953A −
Pin Assignment
Figure 4:
Pin Description
Pin Number
MLPD
-
1
2
3
4
5
6
7
8
9
10
11
WL-CSP
-
C4
B4
B3
B2
C1
A1
B1
A2
A3
A4
-
Gold
Bumped
Die
0
1
2
3
4
5
6
7
8
9
10
-
Pin Name
Pin Type
Description
TEST
VP_SPI
VP_REG
LC1
Internal use
Supply pad
Analog output
Analog I/O
No connection
Positive supply of SPI interface
Regulator output
Connection to tag coil
Ground, die substrate potential
Serial Peripheral Interface enable
(active low)
LC2
VSS
/SS
SCLK
MOSI
MISO
IRQ
Exposed Pad
Digital output /
tristate
Digital output
Supply
Digital input
Supply pad
Serial Peripheral Interface clock
Serial Peripheral Interface data
input
Serial Peripheral Interface data
output
Interrupt request output (active
high)
Exposed pad to be connected to
ground (optional)
ams Datasheet
[v1-04] 2015-Dec-28
Page 5
Document Feedback