XICOR X25330V14-2.5

X25330
32K
4K x 8 Bit
5MHz SPI Serial E2PROM with Block LockTM Protection
FEATURES
DESCRIPTION
•
•
The X25330 is a CMOS 32K-bit serial E2PROM, internally organized as 4K x 8. The X25330 features a
Serial Peripheral Interface (SPI) and software protocol
allowing operation on a simple three-wire bus. The bus
signals are a clock input (SCK) plus separate data in
(SI) and data out (SO) lines. Access to the device is
controlled through a chip select (CS) input, allowing
any number of devices to share the same bus.
•
•
•
•
•
•
•
•
•
5MHz Clock Rate
Low Power CMOS
<1µA Standby Current
<5mA Active Current
2.5V To 5.5V Power Supply
SPI Modes (0,0 & 1,1)
4K X 8 Bits
32 Byte Page Mode
Block Lock™ Protection
Protect 1/4, 1/2 or all of E2PROM Array
Programmable Hardware Write Protection
In-Circuit Programmable ROM Mode
Built-in Inadvertent Write Protection
Power-Up/Down protection circuitry
Write Enable Latch
Write Protect Pin
Self-Timed Write Cycle
5ms Write Cycle Time (Typical)
High Reliability
Endurance: 100,000 cycles
Data Retention: 100 Years
ESD protection: 2000V on all pins
Packages
8-Lead SOIC
14-Lead TSSOP
The X25330 also features two additional inputs that
provide the end user with added flexibility. By
asserting the HOLD input, the X25330 will ignore transitions on its inputs, thus allowing the host to service
higher priority interrupts. The WP input can be used as
a hardwire input to the X25330 disabling all write
attempts to the status register, thus providing a mechanism for limiting end user capability of altering 0, 1/4,
1/2 or all of the memory.
The X25330 utilizes Xicor’s proprietary Direct WriteTM
cell, providing a minimum endurance of 100,000
cycles and a minimum data retention of 100 years.
FUNCTIONAL DIAGRAM
STATUS
REGISTER
WRITE
PROTECT
LOGIC
X DECODE
LOGIC
4K BYTE
ARRAY
32
32 X 256
SO
SI
SCK
CS
HOLD
COMMAND
DECODE
AND
CONTROL
LOGIC
32
32 X 256
64
64 X 256
WP
WRITE
CONTROL
AND
TIMING
LOGIC
32
8
Y DECODE
DATA REGISTER
Direct Write and Block Lock Protection is a trademark of Xicor, Inc.
Xicor, Inc. 1994 - 1997 Patents Pending
7048–1.0 6/18/97 T0/C0/D0 SH
1
7037 FRM F01
Characteristics subject to change without notice
X25330
PIN DESCRIPTIONS
X25330 status register. If the internal write cycle has
already been initiated, WP going LOW will have no
affect on a write.
Serial Output (SO)
SO is a push/pull serial data output pin. During a read
cycle, data is shifted out on this pin. Data is clocked
out by the falling edge of the serial clock.
The WP pin function is blocked when the WPEN bit in
the status register is “0”. This allows the user to install
the X25330 in a system with WP pin grounded and still
be able to write to the status register. The WP pin functions will be enabled when the WPEN bit is set “1”.
Serial Input (SI)
SI is the serial data input pin. All opcodes, byte
addresses, and data to be written to the memory are
input on this pin. Data is latched by the rising edge of
the serial clock.
Hold (HOLD)
HOLD is used in conjunction with the CS pin to pause
the device. Once the part is selected and a serial
sequence is underway, HOLD may be used to pause
Serial Clock (SCK)
The Serial Clock controls the serial bus timing for data
input and output. Opcodes, addresses, or data present
on the SI pin are latched on the rising edge of the
clock input, while data on the SO pin change after the
falling edge of the clock input.
PIN CONFIGURATION
NOT TO SCALE
Chip Select (CS)
When CS is HIGH, the X25330 is deselected and the
SO output pin is at high impedance and unless an
internal write operation is underway, the X25330 will be
in the standby power mode. CS LOW enables the
X25330, placing it in the active power mode. It should
be noted that after power-up, a HIGH to LOW transition
on CS is required prior to the start of any operation.
SOIC
0.197"
Max
CS
1
SO
2
WP
3
V SS
4
Write Protect (WP)
V CC
7
HOLD
6
SCK
5
SI
0.244"
When WP is LOW and the nonvolatile bit WPEN is “1”,
nonvolatile writes to the X25330 status register are
disabled, but the part otherwise functions normally.
When WP is held HIGH, all functions, including
nonvolatile writes operate normally. WP going LOW
while CS is still LOW will interrupt a write to the
TSSOP
PIN NAMES
0.200"
Max
Symbol
CS
X25330
8
Description
Serial Output
SI
Serial Input
SCK
Serial Clock Input
WP
Write Protect Input
VSS
Ground
VCC
Supply Voltage
HOLD
Hold Input
NC
No Connect
1
14
SO
2
13
VCC
HOLD
SO
3
12
HOLD
NC
4 X25330 11
5
10
6
9
NC
7
SI
NC
WP
Chip Select Input
SO
CS
VSS
8
NC
SCK
0.252"
7037 FRM F02
7037 FRM T01
* Pin 2 and Pin 3 are internally connected. Only one CS needs to
be connected externally.
2
X25330
Status Register
The RDSR instruction provides access to the status
register. The status register may be read at any time,
even during a write cycle. The status register is
formatted as follows:
the serial communication with the controller without
resetting the serial sequence. To pause, HOLD must
be brought LOW while SCK is LOW. To resume
communication, HOLD is brought HIGH, again while
SCK is LOW. If the pause feature is not used, HOLD
should be held HIGH at all times.
PRINCIPLES OF OPERATION
7
6
5
4
3
2
1
WPEN
X
X
X
BL1
BL0
WEL
0
WIP
7037 FRM T02
The X25330 is a 4K x 8 E2PROM designed to interface
directly with the synchronous serial peripheral interface (SPI) of many popular microcontroller families.
WPEN, BL0 and BL1 are set by the WRSR instruction.
WEL and WIP are read-only and automatically set by
other operations.
The X25330 contains an 8-bit instruction register. It is
accessed via the SI input, with data being clocked in on
the rising SCK. CS must be LOW and the HOLD and
WP inputs must be HIGH during the entire operation.
The Write-In-Process (WIP) bit indicates whether the
X25330 is busy with a write operation. When set to a
“1”, a write is in progress, when set to a “0”, no write is
in progress. During a write, all other bits are set to “1”.
Table 1 contains a list of the instructions and their
opcodes. All instructions, addresses and data are
transferred MSB first.
The Write Enable Latch (WEL) bit indicates the status
of the “write enable” latch. When set to a “1”, the latch
is set, when set to a “0”, the latch is reset.
Data input is sampled on the first rising edge of SCK
after CS goes LOW. SCK is static, allowing the user to
stop the clock and then resume operations. If the clock
line is shared with other peripheral devices on the SPI
bus, the user can assert the HOLD input to place the
X25330 into a “PAUSE” condition. After releasing
HOLD, the X25330 will resume operation from the
point when HOLD was first asserted.
The Block Lock (BL0 and BL1) bits are nonvolatile and
allow the user to select one of four levels of protection.
The X25330 is divided into four 8K bit segments. One,
two, or all four of the segments may be protected. That
is, the user may read the segments but will be unable
to alter (write) data within the selected segments. The
partitioning is controlled as illustrated below.
Status Register Bits
Write Enable Latch
The X25330 contains a “write enable” latch. This latch
must be SET before a write operation will be
completed internally. The WREN instruction will set the
latch and the WRDI instruction will reset the latch. This
latch is automatically reset upon a power-up condition
and after the completion of a byte, page, or status
register write cycle.
Array Addresses
Protected
BL1
BL0
0
0
None
0
1
$0C00–$0FFF
1
0
$0800–$0FFF
1
1
$0000–$0FFF
7037 FRM T03
Table 1. Instruction Set
Instruction Name
Instruction Format*
Operation
WREN
0000 0110
Set the Write Enable Latch (Enable Write Operations)
WRDI
0000 0100
Reset the Write Enable Latch (Disable Write Operations)
RDSR
0000 0101
Read Status Register
WRSR
0000 0001
Write Status Register
READ
0000 0011
Read Data from Memory Array beginning at selected address
WRITE
0000 0010
Write Data to Memory Array beginning at Selected Address (1 to 32
Bytes)
7037 FRM T04
*Instructions are shown MSB in leftmost position. Instructions are transferred MSB first.
3
X25330
at the next address can be read sequentially by
continuing to provide clock pulses. The address is
automatically incremented to the next higher address
after each byte of data is shifted out. When the highest
address is reached ($0FFF) the address counter rolls
over to address $0000 allowing the read cycle to be
continued indefinitely. The read operation is terminated by taking CS HIGH. Refer to the read E2PROM
array operation sequence illustrated in Figure 1.
The Write-Protect-Enable (WPEN) bit is available for
the X25330 as a nonvolatile enable bit for the WP pin.
WPEN WP WEL
Protected Unprotected Status
Blocks
Blocks
Register
0
X
0
Protected
Protected
Protected
0
X
1
Protected
Writable
Writable
1
LOW
0
Protected
Protected
Protected
1
LOW
1
Protected
Writable
Protected
X
HIGH
0
Protected
Protected
Protected
X
HIGH
1
Protected
Writable
Writable
To read the status register the CS line is first pulled
LOW to select the device followed by the 8-bit RDSR
instruction. After the RDSR opcode is sent, the contents
of the status register are shifted out on the SO line.
Figure 2 illustrates the read status register sequence.
7037 FRM T05
Programmable Hardware Write Protection
The Write Protect (WP) pin and the nonvolatile Write
Protect Enable (WPEN) bit in the Status Register
control the Programmable Hardware Write Protect
feature. Hardware Write Protection is enabled when
WP pin is LOW, and the WPEN bit is “1”. Hardware
Write Protection is disabled when either the WP pin is
HIGH or the WPEN bit is “0”. When the chip is hardware write protected, nonvolatile writes are disabled to
the Status Register, including the Block Lock bits and
the WPEN bit itself, as well as the block-protected
sections in the memory array. Only the sections of the
memory array that are not block-protected can be
written.
Write Sequence
Prior to any attempt to write data into the X25330, the
“Write Enable” latch must first be set by issuing the
WREN instruction (See Figure 3). CS is first taken
LOW, then the WREN instruction is clocked into the
X25330. After all eight bits of the instruction are transmitted, CS must then be taken HIGH. If the user
continues the write operation without taking CS HIGH
after issuing the WREN instruction, the write operation
will be ignored.
To write data to the E2PROM memory array, the user
issues the WRITE instruction, followed by the address
and then the data to be written. This is minimally a
thirty-two clock operation. CS must go LOW and remain
LOW for the duration of the operation. The host may
continue to write up to 32 bytes of data to the X25330.
The only restriction is the 32 bytes must reside on the
same page. If the address counter reaches the end of
the page and the clock continues, the counter will “roll
over” to the first address of the page and overwrite any
data that may have been written.
In Circuit Programmable ROM Mode
Note that since the WPEN bit is write protected, it
cannot be changed back to a LOW state; so write
protection is enabled as long as the WP pin is held
LOW. Thus an In Circuit Programmable ROM function
can be emplemented by hardwiring the WP pin to Vss,
writing to and Block Locking the desired portion of the
array to be ROM, and then programming the WPEN bit
HIGH. The table above defines the program protect
status for each combination of WPEN and WP.
For the write operation (byte or page write) to be
completed, CS can only be brought HIGH after bit 0 of
data byte N is clocked in. If it is brought HIGH at any
other time the write operation will not be completed.
Refer to Figures 4 and 5 below for a detailed illustration of the write sequences and time frames in which
CS going HIGH are valid.
Clock and Data Timing
Data input on the SI line is latched on the rising edge
of SCK. Data is output on the SO line by the falling
edge of SCK.
Read Sequence
When reading from the E2PROM memory array, CS is
first pulled LOW to select the device. The 8-bit READ
instruction is transmitted to the X25330, followed by
the 16-bit address of which the last 12 are used. After
the READ opcode and address are sent, the data
stored in the memory at the selected address is
shifted out on the SO line. The data stored in memory
To write to the status register, the WRSR instruction is
followed by the data to be written. Data bits 0, 1, 4, 5
and 6 must be “0”. Figure 6 illustrates this sequence.
While the write is in progress following a status
register or E2PROM write sequence, the status
register may be read to check the WIP bit. During this
time the WIP bit will be HIGH.
4
X25330
Operational Notes
The X25330 powers-up in the following state:
• The device is in the low power standby state.
• A HIGH to LOW transition on CS is required to enter
an active state and receive an instruction.
• SO pin is high impedance.
• The “write enable” latch is reset.
Hold Operation
The HOLD input should be HIGH (at VIH) under normal
operation. If a data transfer is to be interrupted HOLD
can be pulled LOW to suspend the transfer until it can
be resumed. The only restriction is the SCK input must
be LOW when HOLD is first pulled LOW and SCK
must also be LOW when HOLD is released.
The HOLD input may be tied HIGH either directly to
VCC or tied to VCC through a resistor.
Data Protection
The following circuitry has been included to prevent inadvertent writes:
• The “write enable” latch is reset upon power-up.
• A WREN instruction must be issued to set the “write
enable” latch.
• CS must come HIGH at the proper clock count in order to start a write cycle.
Figure 1. Read E2PROM Array Operation Sequence
CS
0
1
2
3
4
5
6
7
8
9
10
20 21 22 23 24 25 26 27 28 29 30
SCK
INSTRUCTION
16 BIT ADDRESS
SI
15 14 13
3
2
1
0
DATA OUT
HIGH IMPEDANCE
7
SO
6
5
4
3
2
MSB
CS
1
2
3
4
5
6
7
8
9
10 11 12 13 14
SCK
INSTRUCTION
SI
DATA OUT
HIGH IMPEDANCE
7
SO
MSB
5
6
5
4
3
0
7037 FRM F03
Figure 2. Read Status Register Operation Sequence
0
1
2
1
0
7037 FRM F04
X25330
Figure 3. Write Enable Latch Sequence
CS
0
1
2
3
4
5
6
7
SCK
SI
HIGH IMPEDANCE
SO
7037 FRM F05
Figure 4. Byte Write Operation Sequence
CS
0
1
2
3
4
5
6
7
8
9
10
20 21 22 23 24 25 26 27 28 29 30 31
SCK
INSTRUCTION
16 BIT ADDRESS
15 14 13
SI
3
2
DATA BYTE
1
0
7
6
5
4
3
2
1
0
HIGH IMPEDANCE
SO
7037 FRM F06
6
X25330
Figure 5. Page Write Operation Sequence
CS
0
1
2
3
4
5
6
7
8
9
10
20 21 22 23 24 25 26 27 28 29 30 31
SCK
INSTRUCTION
16 BIT ADDRESS
SI
15 14 13
3
DATA BYTE 1
2
1
7
0
6
5
4
3
2
1
0
CS
32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
SCK
DATA BYTE 2
SI
7
6
5
4
3
DATA BYTE 3
2
1
0
7
6
5
4
3
DATA BYTE N
2
1
0
6
5
4
3
2
1
0
7037 FRM F07
Figure 6. Write Status Register Operation Sequence
CS
0
1
2
3
4
5
6
7
8
9
10
11 12 13 14 15
SCK
INSTRUCTION
DATA BYTE
SI
SO
7
6
5
4
3
2
1
0
HIGH IMPEDANCE
7037 FRM F08
7
X25330
ABSOLUTE MAXIMUM RATINGS*
Temperature under Bias....................–65°C to +135°C
Storage Temperature ........................–65°C to +150°C
Voltage on any Pin with Respect
to VSS .........................................................–1V to +7V
D.C. Output Current ............................................. 5mA
(Soldering, 10 seconds) ..............................300°C
*COMMENT
Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device.
This is a stress rating only and the functional operation
of the device at these or any other conditions above
those indicated in the operational sections of this
specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may
affect device reliability.
RECOMMENDED OPERATING CONDITIONS
Temperature
Min.
Max.
Commercial
0°C
+70°C
Industrial
–40°C
+85°C
Supply Voltage
Limits
X25330
5V ±10%
X25330-2.5
2.5V to 5.5V
7037 FRM T06
7037 FRM T07
D.C. OPERATING CHARACTERISTICS (Over the recommended operating conditions unless otherwise specified.)
Symbol
Limits
Min.
Max.
Parameter
Units
Test Conditions
ICC
VCC Supply Current (Active)
5
mA
SCK = VCC x 0.1/VCC x 0.9 @ 5MHz,
ISB
VCC Supply Current (Standby)
1
µA
ILI
Input Leakage Current
10
µA
CS = VCC, VIN = VSS or VCC – 0.3V
VIN = VSS to VCC
VOUT = VSS to VCC
ILO
Output Leakage Current
10
µA
VIL(1)
Input LOW Voltage
–1
VCC x 0.3
V
VIH(1)
Input HIGH Voltage
VCC x 0.7
VCC + 0.5
V
VOL1
Output LOW Voltage
0.4
V
IOL = 3mA, VCC = 5V
VOH1
Output HIGH Voltage
V
IOH = –1.6mA, VCC = 5V
VOL2
Output LOW Voltage
V
IOL = 1.5mA, VCC = 3V
VOH2
Output HIGH Voltage
V
IOH = –0.4mA, VCC = 3V
VCC–0.8
0.4
VCC–0.3
7037 FRM T08
POWER-UP TIMING
Symbol
Max.
Units
TPUR(3)
Power-up to Read Operation
Parameter
Min.
1
ms
TPUW(3)
Power-up to Write Operation
1
ms
7037 FRM T09
CAPACITANCE TA = +25°C, f = 1MHz, VCC = 5V
Symbol
Max.
Units
Test Conditions
CI/O(3)
Output Capacitance (SO)
Parameter
8
pF
VI/O = 0V
CIN(3)
Input Capacitance (SCK, SI, CS, WP, HOLD)
6
pF
VIN = 0V
7037 FRM T10
Notes: (1) VIL min. and VIH max. are for reference only and are not tested.
(2) This parameter is periodically sampled and not 100% tested.
(3) tPUR and tPUW are the delays required from the time VCC is stable until the specified operation can be initiated. These
parameters are periodically sampled and not 100% tested.
8
X25330
EQUIVALENT A.C. LOAD CIRCUIT
5V
A.C. CONDITIONS OF TEST
Input Pulse Levels
3V
VCC x 0.1 to VCC x 0.9
Input Rise and Fall Times
1.44KΩ
1.64KΩ
OUTPUT
1.95KΩ
OUTPUT
4.63KΩ
100pF
10ns
Input and OutputTiming Levels
VCC X 0.5
7037 FRM T11
100pF
7037 FRM F09
A.C. OPERATING CHARACTERISTICS
Data Input Timing
Symbol
Parameter
Min.
Max.
Units
0
5
MHz
fSCK
Clock Frequency
tCYC
Cycle Time
200
ns
tLEAD
CS Lead Time
100
ns
tLAG
CS Lag Time
100
ns
tWH
Clock HIGH Time
80
ns
tWL
Clock LOW Time
80
ns
tSU
Data Setup Time
20
ns
tH
Data Hold Time
20
ns
tRI(4)
tFI(4)
Data In Rise Time
2
µs
Data In Fall Time
2
µs
tHD
HOLD Setup Time
tCD
HOLD Hold Time
40
ns
tCS
CS Deselect Time
100
ns
tWC(5)
Write Cycle Time
40
ns
10
ms
7037 FRM T12
Data Output Timing
Symbol
Parameter
Min.
Max.
Units
0
5
MHz
fSCK
Clock Frequency
tDIS
Output Disable Time
100
ns
tV
Output Valid from Clock LOW
80
ns
tHO
Output Hold Time
tRO(4)
tFO(4)
tLZ(4)
tHZ(4)
Output Rise Time
50
ns
Output Fall Time
50
ns
0
ns
HOLD HIGH to Output in Low Z
50
ns
HOLD LOW to Output in High Z
50
ns
7037 FRM T13
Notes: (4) This parameter is periodically sampled and not 100% tested.
(5) tWC is the time from the rising edge of CS after a valid write sequence has been sent to the end of the self-timed internal nonvolatile
write cycle.
9
X25330
Serial Output Timing
CS
tCYC
tWH
tLAG
SCK
tV
SO
SI
tWL
t HO
MSB OUT
tDIS
MSB–1 OUT
LSB OUT
ADDR
LSB IN
7037 FRM F10
Serial Input Timing
t CS
CS
tLEAD
tLAG
SCK
tSU
SI
tH
tRI
MSB IN
tFI
LSB IN
HIGH IMPEDANCE
SO
7037 FRM F11
10
X25330
Hold Timing
CS
tHD
tCD
tCD
tHD
SCK
tHZ
tLZ
SO
SI
HOLD
7037 FRM F12
11
X25330
PACKAGING INFORMATION
8-LEAD PLASTIC SMALL OUTLINE GULL WING PACKAGE TYPE S
0.150 (3.80)
0.158 (4.00)
0.228 (5.80)
0.244 (6.20)
PIN 1 INDEX
PIN 1
0.014 (0.35)
0.019 (0.49)
0.188 (4.78)
0.197 (5.00)
(4X) 7°
0.053 (1.35)
0.069 (1.75)
0.004 (0.19)
0.010 (0.25)
0.050 (1.27)
0.010 (0.25)
0.020 (0.50) X 45°
0.050" TYPICAL
0.050"
TYPICAL
0° – 8°
0.0075 (0.19)
0.010 (0.25)
0.250"
0.016 (0.410)
0.037 (0.937)
0.030"
TYPICAL
8 PLACES
FOOTPRINT
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
3926 FRM F22.1
12
X25330
PACKAGING INFORMATION
14-LEAD PLASTIC, TSSOP, PACKAGE TYPE V
.025 (.65) BSC
.169 (4.3)
.252 (6.4) BSC
.177 (4.5)
.193 (4.9)
.200 (5.1)
.047 (1.20)
.0075 (.19)
.0118 (.30)
.002 (.05)
.006 (.15)
.010 (.25)
Gage Plane
0° – 8°
Seating Plane
.019 (.50)
.029 (.75)
Detail A (20X)
.031 (.80)
.041 (1.05)
See Detail “A”
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
13
X25330
ORDERING INFORMATION
X25330
P
T
-V
V CC Limits
Blank = 5V ±10%
2.5 = 2.5 to 5.5V
Device
Temperature Range
Blank = Commercial = 0°C to +70°C
I = Industrial = –40°C to +85°C
Package
S8 = 8-Lead SOIC
V14 = 14-Lead TSSOP
PART MARK CONVENTION
X25330
Blank = 8-Lead SOIC
V = 14-Lead TSSOP
X
X
Blank = 5V ±10%, 0°C to +70°C
I = 5V ±10%, –40°C to +85°C
AE = 2.5V to 5.5V, 0°C to 70°C
AF = 2.5V to 5.5V, –40°C to +85°C
LIMITED WARRANTY
Devices sold by Xicor, Inc. are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. Xicor, Inc.
makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the
described devices from patent infringement. Xicor, Inc. makes no warranty of merchantability or fitness for any purpose. Xicor, Inc. reserves the
right to discontinue production and change specifications and prices at any time and without notice.
Xicor, Inc. assumes no responsibility for the use of any circuitry other than circuitry embodied in a Xicor, Inc. product. No other circuits, patents,
licenses are implied.
U.S. PATENTS
Xicor products are covered by one or more of the following U.S. Patents: 4,263,664; 4,274,012; 4,300,212; 4,314,265; 4,326,134; 4,393,481;
4,404,475; 4,450,402; 4,486,769; 4,488,060; 4,520,461; 4,533,846; 4,599,706; 4,617,652; 4,668,932; 4,752,912; 4,829, 482; 4,874, 967;
4,883, 976. Foreign patents and additional patents pending.
LIFE RELATED POLICY
In situations where semiconductor component failure may endanger life, system designers using this product should design the system with
appropriate error detection and correction, redundancy and back-up features to prevent such an occurence.
Xicor's products are not authorized for use in critical components in life support devices or systems.
1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain
life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably
expected to result in a significant injury to the user.
2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the
failure of the life support device or system, or to affect its safety or effectiveness.
14