EMMICRO EM4056B6WW11E

EM MICROELECTRONIC - MARIN SA
EM4056
2KBIT Read/Write with ANTICOLLISION
Contactless Identification Device
•
Description
The EM4056 is a CMOS integrated circuit intended for
use in contactless Read/Write transponders.
The user’s configurable 2 kbits EEPROM memory
contained in the chip is organised in 125 words of 16 bits,
each word can be irreversibly protected against reading
or/and writing attempts.
The user can define a password and protect part or all of
the memory.
Serial and identification numbers are laser programmed
during IC manufacturing. A reserved application
numbering may be made available and customer specific
on request.
The EM4056 transmits its data towards the reader by
amplitude modulation of the magnetic field and receives
the commands from the reader in a similar way.
Simple set of commands allow the dialogue between the
EM4056 and the reader. Read and write commands
access directly to an address of memory.
The EM4056 has a built-in anticollision protocol which
allows an unlimited number of transponders in the reader
field to dialogue simultaneously.
The transmission antenna is the only external element
required, all the other elements are integrated on chip.
Features
•
•
•
2 kBits EEPROM organized in 125 words of 16 bits
3 words of 16 Bits Laser ROM for application number
and serial number
Programmable (OTP) Read and/or Write Protection
on every word
•
•
•
•
•
•
•
•
•
•
•
•
•
Programmable PIN coverage of the memory (0, 25,
50, 75 or 100 %)
Power check for EEPROM Write operation
Reader Talk First communication protocol
Data transmission performed by Amplitude
Modulation (ASK) and Biphase (CDP) coding
Data rate 2 KBauds (Bit Period = 64 periods of carrier
frequency)
100 to 150kHz carrier frequency
Long range Read/Write operations
Block check of data transmission (CRC)
Anticollision protocol based on unique ID
number(unlimited number of tags)
PIN Code identification linked with counter of false
attempts
On chip arithmetic operation (addition, comparison of
secret and non secret data, etc.)
340pF ± 3% on chip Resonant Capacitor
No external supply buffer capacitance
On chip Rectifier and Voltage Limiter
Applications
•
•
•
•
•
Ticketing
Hands free Access control
Prothesis identification
Prepayment devices
Manufacturing automation with portable database
•
Industrial logistics
Typical Operating Configuration
C2
EM4056
L
C1
Typical value for inductance L is 4.78mH at fO = 125 KHz
Fig. 1
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EM4056
Block Diagram
CLK
Analog
Circuit
Antenna
(Coil)
Logic Circuit
Serial Output
EEPROM
Power Supply
Addressing
Memory
Safety
(incl. PIN Code)
Laser ROM
125kHz EM coupling
3x16 bit
Modulator
Adder
Write/Read
Protection (OTP)
Anticollision
125 x 16 bit
EEPROM
Demodulator
Serial Input
Fig. 2
System Principle
125kHz EM coupling
Reader
EM4056
Command Mode
Reader
Oscillator
Reader Coil
Reader
Coil
Modulator
RS232
Serial
Interface
Decoder
Demodulator
Transponder Coil
Answer Mode
Transponder Coil
Reader Coil
Fig. 3
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EM4056
Absolute Maximum Ratings
Parameter
Voltage
on
Power
Supply pads
Voltage on other pads
Symbol
VDD
Max. AC peak current
induced on COIL1 and
COIL2
Storage temperature
ICOIL
Operating temperature
Electrostatic discharge
max. to MIL-STS-883C
method 3015
VPAD
Handling Procedures
Min.
-0.3
Max.
6.0
This device has built-in protection against high static
voltages or electric fields; however, anti-static precautions
must be taken as for any other CMOS component. Unless
otherwise specified, proper operation can only occur when
all terminal voltages are kept within the voltage range.
Unused inputs must always be tied to a defined logic
voltage level.
Units
V
VSS - 0.3 VDD+ 0.3
V
- 30
+ 30
mAp
TSTORE
-55
TOP
VESD
-40
+125
oC
+85
oC
1000
V
Operating Conditions
Parameter
Stresses above these listed maximum ratings may cause
permanent damages to the device. Exposure beyond
specified operating conditions may affect device reliability
or cause malfunction.
Symbol Min
Max
Units
(Note 1)
Vpp
-10
+10
mAp
fCOIL
100
150
kHz
TOP
-40
+85
°C
Max. AC Voltage on COIL
VCOIL
Max. AC coil current
ICOIL
Carrier frequency
Operating temperature
Note 1: Defined by forcing 10mA on Coil1-Coil2
Electrical Characteristics
Unless otherwise specified : VDD = 4.0 V, VSS = 0 V, TOP = 25°C, VCOIL = 4.5 Vpp, fCOIL = 125 KHz Sine wave
Parameter
Supply voltage (not regulated)
Supply voltage (regulated)
Symbol
Conditions
Min
Typ
Max
(Note1)
VPOS-REG
Unit
V
V
VDD
VPOS-REG = max (note 1)
3.4
Min. EEPROM Read voltage
VRD
Read mode
2.5
Min. EEPROM Write voltage
VWR
Write mode
EEPROM Read current
IRD
Read mode
19
25
IWR
Write mode
60
80
µA
IPWCHK
VDD = 4.0 V
70
95
µA
2.75
3.10
V
EEPROM Write current
Power check EEPROM write
current
EEPROM pwr check threshold
voltage
EEPROM data endurance
EEPROM retention
Voltage drop
modulator
VSS
on
NCY
Erase all / Write all
TOP = 55oC after 105 cycles
VON
ICOIL = 100 µA
ICOIL = 5 mA
CCOIL
POR voltage (high)
VPRH
MONOFLOP delay
TMONO
Min. voltage of clock extractor 1
(note 4)
Min. voltage of clock extractor 2
(note 5)
2.52
TRET
Resonance capacitor
4.3
V
2.5
VPWCHK
(note 3)
VCOIL-
(note 2)
V
105
10
330
VDD rising
µA
cycle
year
0.50
2.50
V
V
340
350
pF
2.0
2.6
V
50
85
VCLK1min
Vcoil1-coil2 (min for extraction)
4.5
µs
Vpp
VCLK2min
Vcoil1-coil2 (min for extraction)
1.0
Vpp
25
Note 1: Max. supply voltage (not regulated) is defined by forcing a DC current 10 mAp in pins COIL1-COIL2
Note 2: The circuit is not functional under low level POR voltage
Note 3: Based on 1000 hours measurement at 150oC
Copyright © 2005, EM Microelectronic-Marin SA
Note 4: Uplink
Note 5: downlink
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EM4056
Timing Characteristics
Parameter
Symbol
Conditions
Modulation duration
Typ
ON OFF ON
Tb0
Bit 0
26
8
Tb1
Tab
Bit 1
Start bit
36
16
8
8
Emission Bit Period
8
Units
RF periods
Tbit
64
RF periods
Tbitarb
32
RF periods
Select processing time
Tsp
190
RF periods
Read processing time
126
RF periods
Write processing time
Trp
Twp
3134
RF periods
Arb1 processing time
Ta1p
62
RF periods
Arb2 processing time
Ta2p
10
RF periods
Arbitration format duration
Tarb
Tro
115
ms
24.5
Select format duration
Ts
19.1
Prot format duration
Tp
32.2
Read format duration
Tr
20.3
Write format duration
Tw
36.6
Comp format duration
Tc
16.6
Login format duration
EEPROM Write duration
Tl
Reception Bit Period
Reception Bit Period Arbitration
Read Rom format duration
Tee
35.1
20.0
VDD = 3V
Functional Description
General
The EM4056 has a read enable bit (RdEn) realised with a flip-flop cell. If the RdEn bit is set to « 0 », the transponder is
always allowed to answer otherwise it answers only on special commands.
At power on, the default value of the RdEn bit is 0. Therefore, after switching the field on, the RdEn bit of all known tags may
be set by the reader in order to separate them in two groups.
The block check sequence uses a 8 bits CRC which is the same polynom for all CRC blocks.
In addition, the CRC block from the EM4056 to the reader is sent in the format of the BitVal frame (see arbitration mode) to
increase the error detection rate in the reader.
1
Bit
0
Read Prot
Address Bit
17
0000000
Write Prot
Memory organisation
Bit 0 is defined as the first bit output
LASER ROM (3 * 18)
0000010
EEPROM (123 * 18)
1111110
1111111
Configuration Word
PIN Word
Config Word definition + Laser Rom area definition
Fig.4
The Read Protected and the Write Protected bit are OTP bit. Once written to one,
it is definitively locked. No possibility to erase them to zero.
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EM4056
ROM organisation
Address
Datas
0000000
0000001
0000010
bit17
B15
B31
L7
bit2
B0
B16
C0
L0 C7
Wp
bit1
1
1
1
Rp
bit0
0
0
0
B31-B0 unique code number.
L7-L0
8-bit customer ID, standard version = 65hex, 101dec.
C7 – C0
CRC calculated on bits B31 to B0 and L7 to L0.
(CRC block diagram see figure 4).
Note : EM4056 with different customer ID will also have a different unique code number.
Commands structure
Command
ReadRom
SelToggle
SelTag
DeselTag
Prot
Read
Write
Add
Comp
Start Arbitration
Continue if “0”
Continue if “1”
Abort Arbitration
MSB
Code
0010
LSB
0100
0101
0110
1000
1010
1100
1101
1110
0001
00
11
01 or 10
CRC Block Diagram
7
6 5
4
3 2 1
0
MSB
Data Input
LSB
X7
X5
X4
X1
X0=1
Exclusive OR
X
Shift Register
CRC Generating polynomial = X7+X5+X4+X+1
Fig. 5
In uplink the CRC is calculated on all bits of the command (startbit excluded), MSB first.
In dowlink the CRC is calculated on all bits of the answer, first bit sent by the chip first.
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EM4056
ReadRom
A ReadRomEn command enables only transponders in the field with RdEn bit set to « 0 » to answer.
With this command, the address of a single new tag entered in the field can be detected because all known transponders
are not allowed to answer if they are deactivated by the RdEn bit (RdEn=1). If more than one transponder answer a CRC
error will be detected and it becomes necessary to perform an arbitration to find all new transponder addresses.
The command is faster than a full arbitration cycle for new tags.
The ReadRomEn command frame consists of three blocks and has a constant length of 13 bits.
The Start bit allows the transponder to synchronise to the new command frame. After the Start bit, the frame contains four
bits for the Command. A CRC block of 8 bits is calculated over the Command and appended to the end.
The transponder frame has a length of 40 bits and starts with the 32 bits ROM block. A CRC block of 8 bits is calculated
over the transponder address (ROM) and appended to the end.
1 bit
Reader
Start
4 bits
MSB
ReadRom
8 bits
X8
CRC
Transponder
tsp
32 bits
MSB
ROM
8 bits
X8
CRC
Fig. 6
SelToggle
A SelToggle command addresses a transponder and toggles the RdEn bit (0→1 or 1→0). The transponder returns a frame
with the changed value of RdEn bit followed by a CRC.
The SelToggle command frame consists of four blocks and has a constant length of 45 bits.
The Start bit allows the transponder to synchronise to the new command frame. After the Start bit the frame contains four
bits for the Command. Next to the Command, a sequence of 32 bits follows with the transponder address. A CRC block of 8
bits is calculated over the Command and the transponder address and appended to the end.
The transponder frame has a length of 10 bits and starts with the RdEn bit and the "not RdEn" bit. A CRC block of 8 bits is
calculated over the RdEn and the "not RdEn" and appended to the end.
1 bit
Reader
Start
4 bits
MSB
SelToggle
32 bits
MSB
ROM
8 bits
X8
CRC
2 bits
Transponder
tsp
RdEn nRdEn
8 bits
X8
CRC
Fig. 7
SelTag
The SelTag command address a transponder with its 32 bit address (ROM) and set the flag Select to 1. After this command,
the selected transponder can answer to commands : Read, Write, Prot, Add, Comp and Login.
1 bit
Reader
Start
4 bits
MSB
SelTag
32 bits
MSB
ROM
8 bits
X8
CRC
2 bits
Transponder
tsp
Sel nSel
8 bits
X8
CRC
Fig. 8
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EM4056
DeselTag
The DeselTag command address a transponder with its 32 bit address (ROM) and reset the flag Select to 0.
1 bit
Reader
Start
4 bits
MSB
DeselTag
32 bits
MSB
ROM
8 bits
X8
CRC
2 bits
8 bits
X8
Transponder
tsp
Sel nSel
CRC
Fig. 9
Prot
Prot command for writing the 2 (OTP) protection bit (read and write) at the specified address.
1 bit
Reader
Start
4 bits
MSB
Prot
8 bits
MSB
Address
2 bits
MSB
Wp/Rp
8 bits
X8
CRC
2 bits
Transponder
twp
WOk nWOk
8 bits
X8
CRC
Fig. 10
Wp=1, the specified address is protected against writing.
Rp=1, the specified address is protected against reading.
WOk=1, the protection bit has been successfully written to one.
Read
Read command to get a 16-bit word located at the specified address. If the address is read protected, the circuit transmits a
65535 value.
1 bit
Reader
Start
4 bits
MSB
Read
8 bits
MSB
Address
8 bits
X8
CRC
16 bits
3 bits
8 bits
MSB
X8
trp
Datas
Prot
CRC
Prot = (Wp / Rp / Suc)
Transponder
Fig. 11
Datas
12345 dec
65535 dec
65535 dec
65535 dec
Rp
0
0
1
0
Suc
0
0
x
1
Definition
Data = 12345
Data = 65535
Read protected
Read protected by PIN
Wp=1, the specified address is protected against writing.
Rp=1, the specified address is protected against reading.
Suc=1, the specified address is protected by the PIN against reading.
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EM4056
Write
Write command for 16 bits of data at the specified address.
1 bit
Reader
Start
4 bits
MSB
Write
8 bits
MSB
Address
16 bits
MSB
Datas
8 bits
X8
CRC
2 bits
Transponder
8 bits
X8
CRC
twp WOk nWOk
Fig. 12
WOk=1, the write operation has been successfully executed.
When a word is written at the address (Adr 126), where the configuration is located this command is restricted to write the
uppermost data (Dat_15 à Dat_4), the lower address (Dat_3 to Dat_0) being reserved for safeguarding the PIN counter.
The data at the address of the configuration are:
15
Z_Suc[2:0]
0
M_Suc
No_Ant
Sec
Conf[2:0]
NU NU NU Alm
Pin[2:0]
Fig. 13
where :
•
M_suc : selects a internal mode for which no reading nor writing can extract or engrave valid data into the area of the
memory presently protected by the PIN code.
M_suc=1, area of memory is protected by PIN.
•
Z_suc[2 :0] : determines the address area which is protected by the PIN code. (0% [000], 25%[100], 50%[101], 75
%[110] or 100%[111]).
Z_suc[2:0]
000
100
101
110
111
•
•
•
•
•
Area protected
00 %
25 %
50 %
75 %
100 %
Addresses protected
None, incl. PIN
Word 127 – Word 96
Word 95 – Word 64
Word 63 – Word 32
Word 31 – Word 0
No_Ant : selects the bit "Egal_ROM" and disables the anticollision mode.
No_Ant=1, no anticollision, the tag is always selected (Sel=1).
Sec=1, enables the counter of false attempts for the password (PIN).
Sec=0, counter is disabled.
Conf[2 :0] : represents the maximum number of attempts for finding a valid PIN before definitive lock of the card for
writing.
Pin[2 :0] : represents the number of remaining attempts for finding the correct PIN.
Alm : alarm bit indicates a permanent lock of the card against write attempts. This bit is activated as soon as the number
of PIN erroneous introduction is surpassed.
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EM4056
Add
Add command to add one 16-bit data word to another 16-bit data word pointed by the specified address, this command
writes the sum at the specified address. It is possible to add a value to an already protected memory location that has been
protected against reading, but not to a memory location that has been protected against writing attempts.
1 bit
Reader
Start
4 bits
MSB
Add
8 bits
MSB
Address
16 bits
MSB
Datas
8 bits
X8
CRC
2 bits
Transponder
twp WOk nWOk
8 bits
X8
CRC
Fig. 14
Comp
Compares a 16 bits data word with another word pointed by the specified address.
It is possible to perform a comparison with a value pointed by a read protected address.
But it is impossible to compare a value with another one in the opaque area without entering the PIN. In the case of PIN
violation, the result of the comparison is always false.
Ega=1, comparison successful.
1 bit
Reader
Start
4 bits
MSB
Comp
8 bits
MSB
Address
16 bits
MSB
Datas
8 bits
X8
CRC
2 bits
Transponder
trp
Ega nEga
8 bits
X8
CRC
Fig. 15
Login
Compares a 16 bit data word with the PIN word at the address 127.
When a PIN comparison is made (Adr 127) and the identity is established, a write operation occurs in the EEPROM, PIN =
CONF , the success bit is released (SUC = 0), the PIN counter is decremented (PIN = PIN - 1) and the corresponding new
value is written in the EEPROM.
After n erroneous attempts (PIN=0), the ALM bit is set (ALM = 1), and written in the EEPROM. Since that moment the entire
memory is irreversibly locked. The unprotected data words (Rp=0) remain accessible for reading the information they are
containing.
1 bit
Reader
Start
4 bits
16 bits
8 bits
MSB LSB MSB LSB X8
1
Login
Datas
CRC
4 bits
Transponder
twp Ega nEga WOk nWOk
8 bits
X8
1
CRC
Fig. 16
Ega=1, password ok. Wok=1, writing operation successful.
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EM4056
Arbitration commands
The arbitration mode is a sophisticated command avoiding collisions among transponders. The arbitration method is based
on the method of multiprocessor bus arbitration.
This feature allows the identification of a transponder out of a group, even if they entered the electromagnetic field at the
same time. At each arbitration, the reader detects one address of a new transponder.
The arbitration session starts with a special StartArbitration command. If the RdEn bit of the transponder is « 0 », then the
transponder belongs to the active group. The arbitration commands will only act on the transponders of the active group.
StartArbitration
After the Start bit, the reader sends a command field which indicates the beginning of an arbitration cycle. An 8 bits CRC
block calculated over the StartArbitration command completes this information.
The transponder returns the first BitVal frame corresponding to the LSB of its 32 bits addresses.
Start of arbitration
1 bit
Reader Start
4 bits
MSB
Start_Arbit
8 bits
MSB
CRC
Transponder
1 bit
2 bits
MSB
Start Continue
6 bits
Bit0 Bit0 X X Bit1 Bit1
ta1p
LSB ROM
ta2p
Fig. 17
BitVal Frame
The BitVal frame consists of 6 bits. If the Nth bit of its address is logic « 0 », the transponder sends two « 0 » at the position
Bit0. If the Nth bit of its address is logic « 1 », the transponder sends two « 0 » at the positions Bit1. The bit repetition
increases the transmission reliability.
The response value of the different transponders is coded with the time position of the answer. Therefore no answer
conflicts are generated.
Note: Reception Bit Period is 32 RFclocks for all the arbitration (BitVal frame and CRC).
BitVal frame
Bit0
Bit0
Å 32 Rf period Æ
X
BitVal = 0
0
0
X
BitVal = 1
X
X
X
X
X
X
Bit1
Bit1
X
X
0
0
Fig. 18
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EM4056
Continue command
After receiving the BitVal frame from the different transponders in the field the reader decides whether the tags with « 0 » or
« 1 » should continue the arbitration process and communicates this with the Continue frame. The transponders whose last
BitVal was not identical with the confirmation in the Continue frame stop the arbitration process and wait for a new
command.
Arbitration in progress
1 bit
Reader
Start
2 bits
MSB
Continue
Transponder
1 bit
2 bits
MSB
Start Continue
ta1p
6 bits
Bit0 Bit0 X X Bit1 Bit1
nth BitVal
ta2p
ta1p
6 bits
Bit0 Bit0 X X Bit1 Bit1
n+1th BitVal
Fig. 19
When the Continue frame of the 32nd bit is processed, only one transponder is left. This new identified tag sets the RdEn bit
to 1 and belongs no longer to the active group. The arbitration cycle is completed by a transponder frame for selective
commands (RdEn,CRC). The CRC is calculated like a transponder frame for general commands. This means the CRC is
calculated over ROM and RdEn of the transponder in order to increase the reliability of the arbitration.
End of arbitration
1 bit
Reader
Transponder
Start
2 bits
MSB
Continue
1 bit
2 bits
MSB
Start Continue
ta1p
6 bits
Bit0 Bit0 X X Bit1 Bit1
32th BitVal
ta2p
ta1p
8 bits
MSB
CRC
Fig. 20
To identify the address of a transponder, it takes 115 ms (including overhead as mentioned before). That makes it possible
to detect about 8.7 new transponders per second, independent of the number of transponders in the electromagnetic field.
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EM4056
Example of Arbitration protocol *
Read ROM
No
CRC error ?
Yes
Reset flag
Read next bit
(from LSB to MSB)
Yes
No
0 and 1 ?
Set flag
Yes
Chosen bit: 0
0?
Chosen bit: 0
No
No
Chosen bit: 1
Yes
MSB ?
Chosen bit: 1
No
Flag set ?
Yes
All tags are identified
*patented by Biel School of Negineering, MicroLab I3S
Fig. 21
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EM4056
Pad Location
Pad Assignment
Pin
Name
1
C1
2
Description
coil connection
TEST_CLK test pad with pull down
3
VPOS
4
VDD
5
4
169
positive supply
7
TEST_OUT test pad output
3
1673
2
7
6
VSS
negative supply
7
TEST
test pad with pull down
8
C2
2607
1850
3175
EM4056
1955
5
6
unregulated positive supply
8
coil connection
1
409
151
666
525
Y
2159
X
C1, C2 pad size : 200 X 600
Other pads size : 100 X 100
All dimensions in µm
Fig. 22
Package Information
CID Package
PCB Package
FRONT VIEW
Y
K
J
TOP VIEW
B
D
Z
MARKING
AREA
A
SYMBOL
A
B
D
e
F
g
J
K
R
MIN
8.2
3.8
5.8
0.38
1.25
0.3
0.42
0.115
0.4
TYP
8.5
4.0
6.0
0.5
1.3
0.4
0.44
0.127
0.5
MAX
8.8
4.2
6.2
0.62
1.35
0.5
0.46
0.139
0.6
X
C2
Dimensions are in mm
R
SYMBOL
X
Y
Z
e
C2
C1
F
F
MIN
C1
TYP
8.0
4.0
MAX
1.0
Dimensions are in mm
g
Fig. 23
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Fig. 24
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EM4056
Ordering Information
Part Number
EM4056B6WW11E
EM4056B6WP11
EM4056B6CI2LC
EM4056B6CB2RC
Bit
coding
Bi-phase
Bi-phase
Bi-phase
Bi-phase
Cycle/
bit
64
64
64
64
Package / Die Form
Unsawn wafer, 11mils thickness
Die in waffle pack, 11mils thickness
CID package, 2 pins (length = 2.5mm)
PCB package, 2 pins
Delivery Form / Bumping
With gold bumps
No bumps
Bulk
Bulk
For other packages, please contact EM Microelectronic-Marin SA
Product Support
Check our Web Site under Products/RF Identification section.
Questions can be sent to [email protected] com
EM Microelectronic-Marin SA (EM) makes no warranty for the use of its products, other than those expressly contained in the Company's
standard warranty which is detailed in EM's General Terms of Sale located on the Company's web site. EM assumes no responsibility for
any errors which may appear in this document, reserves the right to change devices or specifications detailed herein at any time without
notice, and does not make any commitment to update the information contained herein. No licenses to patents or other intellectual
property of EM are granted in connection with the sale of EM products, expressly or by implications. EM's products are not authorized for
use as components in life support devices or systems.
© EM Microelectronic-Marin SA, 04/05, Rev. E
Copyright © 2005, EM Microelectronic-Marin SA
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