Intersil ISL33002IRT2Z I2c bus buffer with rise time accelerators and hot swap capability Datasheet

I2C Bus Buffer with Rise Time Accelerators and
Hot Swap Capability
ISL33001, ISL33002, ISL33003
Features
The ISL33001, ISL33002, ISL33003 are 2-Channel Bus Buffers
that provide the buffering necessary to extend the bus
capacitance beyond the 400pF maximum specified by the I2C
specification. In addition, the ISL33001, ISL33002, ISL33003
feature rise time accelerator circuitry to reduce power
consumption from passive bus pull-up resistors and improve
data-rate performance. All devices also include hot swap circuitry
to prevent corruption of the data and clock lines when I2C devices
are plugged into a live backplane, and the ISL33002 and
ISL33003 add level translation for mixed supply voltage
applications. The ISL33001, ISL33002, ISL33003 operate at
supply voltages from +2.3V to +5.5V at a temperature range of
-40°C to +85°C.
• 2 Channel I2C compatible bi-directional buffer
Summary of Features
PART
NUMBER
LEVEL
TRANSLATION
• +2.3VDC to +5.5VDC supply range
• >400kHz operation
• Bus capacitance buffering
• Rise time accelerators
• Hot swapping capability
• ±6kV Class 3 HBM ESD protection on all pins
• ±12kV HBM ESD protection on SDA/SCL pins
• Enable pin (ISL33001 and ISL33003)
• Logic level translation (ISL33002 and ISL33003)
• READY logic pin (ISL33001)
ENABLE READY
PIN
PIN
ACCELERATOR
DISABLE
• Accelerator disable pin (ISL33002)
ISL33001
No
Yes
Yes
No
• Pb-free (RoHS Compliant) 8 Ld SOIC (ISL33001 only),
8 Ld TDFN (3mmx3mm) and 8 Ld MSOP packages
ISL33002
Yes
No
No
Yes
• Low quiescent current . . . . . . . . . . . . . . . . . . . . . . . 2.1mA typ
ISL33003
Yes
Yes
No
No
• Low shutdown current . . . . . . . . . . . . . . . . . . . . . . . . 0.5µA typ
Applications
Related Literature
• AN1543, “ISL33001MSOPEVAL1Z, ISL33002MSOPEVAL1Z,
ISL33003MSOPEVAL1Z Evaluation Board User’s Manual”
• AN1637, “Level Shifting Between 1.8V and 3.3V Using I2C
Buffers”
VCC1
+3.3V
+5.0V
• I2C bus extender and capacitance buffering
• Server racks for telecom, datacom, and computer servers
• Desktop computers
• Hot-swap board insertion and bus isolation
100kHz I2C BUS WITH 2.7kΩ PULL-UP RESISTOR
AND 400pF BUS CAPACITANCE
VCC2
WITHOUT BUFFER
µC
SCL
SDA
ISL33003
SCL
I2C
DEVICE
A
EN
I2C
DEVICE
B
VOLTAGE (1V/DIV)
SDA
BACK
PLANE
WITH BUFFER
GND
TIME (2µs/DIV)
FIGURE 1. TYPICAL OPERATING CIRCUIT
July 11, 2014
FN7560.6
1
FIGURE 2. BUS ACCELERATOR PERFORMANCE
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC. 2010-2014. All Rights Reserved
Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
ISL33001, ISL33002, ISL33003
Ordering Information
PART NUMBER
(Notes 1, 2, 3)
PART
MARKING
TEMP. RANGE
(°C)
PACKAGE
(Pb-free)
PKG.
DWG. #
ISL33001IRTZ
3001
-40 to +85
8 Ld TDFN (0.65mm Pitch)
L8.3x3A
ISL33001IRT2Z
01R2
-40 to +85
8 Ld TDFN (0.5mm Pitch)
L8.3x3H
ISL33001IBZ
33001 IBZ
-40 to +85
8 Ld SOIC
M8.15
ISL33001IUZ
33001
-40 to +85
8 Ld MSOP
M8.118
ISL33002IRTZ
3002
-40 to +85
8 Ld TDFN (0.65mm Pitch)
L8.3x3A
ISL33002IRT2Z
02R2
-40 to +85
8 Ld TDFN (0.5mm Pitch)
L8.3x3H
ISL33002IUZ
33002
-40 to +85
8 Ld MSOP
M8.118
ISL33003IRTZ
3003
-40 to +85
8 Ld TDFN (0.65mm Pitch)
L8.3x3A
ISL33003IRT2Z
03R2
-40 to +85
8 Ld TDFN (0.5mm Pitch)
L8.3x3H
ISL33003IUZ
33003
-40 to +85
8 Ld MSOP
M8.118
ISL33001MSOPEVAL1Z
ISL33001 Evaluation Board
ISL33002MSOPEVAL1Z
ISL33002 Evaluation Board
ISL33003MSOPEVAL1Z
ISL33003 Evaluation Board
NOTES:
1. Add “-T*” suffix for tape and reel. Please refer to TB347 for details on reel specifications.
2. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte
tin plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil
Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
3. For Moisture Sensitivity Level (MSL), please see device information page for ISL33001, ISL33002, ISL33003. For more information on MSL please
see techbrief TB363.
Pin Configurations
ISL33001
(8 LD SOIC, MSOP)
TOP VIEW
ISL33001
(8 LD TDFN)
TOP VIEW
8
VCC1
7
SDA_OUT
SCL_IN 3
6
SDA_IN
GND 4
5
READY
EN 1
SCL_OUT 2
PAD
EN
1
8
VCC1
SCL_OUT
2
7
SDA_OUT
SCL_IN
3
6
SDA_IN
GND
4
5
READY
ISL33002
(8 LD MSOP)
TOP VIEW
ISL33002
(8 LD TDFN)
TOP VIEW
VCC2 1
8
VCC1
7
SDA_OUT
SCL_IN 3
6
SDA_IN
GND 4
5
ACC
SCL_OUT 2
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PAD
2
VCC2
1
8
VCC1
SCL_OUT
2
7
SDA_OUT
SCL_IN
3
6
SDA_IN
GND
4
5
ACC
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Pin Configurations
(Continued)
ISL33003
(8 LD MSOP)
TOP VIEW
ISL33003
(8 LD TDFN)
TOP VIEW
VCC2 1
8
VCC1
7
SDA_OUT
SCL_IN 3
6
SDA_IN
GND 4
5
EN
SCL_OUT 2
VCC2
1
8
VCC1
SCL_OUT
2
7
SDA_OUT
SCL_IN
3
6
SDA_IN
GND
4
5
EN
PAD
Pin Descriptions
PIN
PIN NAME NUMBER
FUNCTION
NOTES
VCC1
8
VCC1 power supply, +2.3V to +5.5V. Decouple VCC1 to ground with a high frequency
0.01µF to 0.1µF capacitor.
VCC2
1
VCC2 power supply, +2.3V to +5.5V. Decouple VCC2 to ground with a high frequency ISL33002 (8 LD TDFN, 8 LD MSOP)
0.01µF to 0.1µF capacitor. In level shifting applications, SDA_OUT and SCL_OUT logic ISL33003 (8 LD TDFN, 8 LD MSOP)
thresholds are referenced to VCC2 supply levels. Connect pull-up resistors on these
pins to VCC2.
GND
4
Device Ground Pin
EN
1
Buffer Enable Pin. Logic “0” disables the device. Logic “1” enables the device. Logic ISL33001 (8 LD TDFN, 8 LD SOIC, MSOP)
threshold referenced to VCC1.
ISL33003 (8 LD TDFN, 8 LD MSOP)
5
READY
5
ISL33001 only
Buffer active ‘Ready’ open drain logic output. When buffer is active, READY is high
impedance. When buffer is inactive, READY is low impedance to ground. Connect to
10kΩ pull-up resistor to VCC1.
ACC
5
Rise Time Accelerator Enable Pin. Logic “0” disables the accelerator. Logic “1”
enables the accelerator. Logic threshold referenced to VCC1.
SDA_IN
6
Data I/O Pins
SDA_OUT
7
SCL_IN
3
SCL_OUT
2
PAD
ISL33002 only
Clock I/O Pins
Thermal pad should be connected to ground or floated.
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Thermal Pad; TDFN only
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Absolute Maximum Ratings
Thermal Information
(All voltages referenced to GND)
VCC1, VCC2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to +7V
SDA_IN, SCL_IN, SDA_OUT, SCL_OUT, READY. . . . . . . . . . . . . -0.3V to +7V
EN, ACC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to +(VCC1 + 0.3)V
Maximum Sink Current (SDA and SCL Pins) . . . . . . . . . . . . . . . . . . . . 20mA
Maximum Sink Current (READY pin) . . . . . . . . . . . . . . . . . . . . . . . . . . . 7mA
Latch-Up Tested per JESD78, Level 2, Class A . . . . . . . . . . . . . . . . . . 85°C
ESD Ratings. . . . . . . . . . . . . . . . . . . . . . See “ESD PROTECTION” on page 5
Operating Conditions
Temperature Range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40°C to +85°C
VCC1 and VCC2 Supply Voltage Range . . . . . . . . . . . . . . . . . +2.3V to +5.5V
Thermal Resistance
JA (°C/W) JC (°C/W)
47
4
8 Ld TDFN Package (Notes 5, 6) . . . . . . . . . .
(0.50mm Pitch)
8 Ld TDFN Package (Notes 5, 6) . . . . . . . . . .
48
6
(0.65mm Pitch)
8 Ld MSOP Package (Notes 4, 7) . . . . . . . . .
151
50
8 Ld SOIC Package (Notes 4, 7) . . . . . . . . . .
120
56
Maximum Storage Temperature Range . . . . . . . . . . . . . -65°C to +150°C
Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . +150°C
Pb-Free Reflow Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . see TB493
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product
reliability and result in failures not covered by warranty.
NOTES:
4. JA is measured with the component mounted on a high effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
5. JA is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See Tech
Brief TB379.
6. For JC, the “case temp” location is the center of the exposed metal pad on the package underside.
7. For JC, the “case temp” location is taken at the package top center.
Electrical Specifications
VEN = VCC1, VCC1 = +2.3V to +5.5V, VCC2 = +2.3V to +5.5V, unless otherwise noted (Note 8). Boldface limits apply
over the operating temperature range, -40°C to +85°C.
PARAMETER
SYMBOL
CONDITIONS
TEMP
(°C)
MIN
(Note 9)
TYP
MAX
(Note 9)
UNITS
Full
2.3
-
5.5
V
POWER SUPPLIES
VCC1 Supply Range
VCC1
VCC2 Supply Range
VCC2
ISL33002 and ISL33003
Full
2.3
-
5.5
V
Supply Current from VCC1
ICC1
VCC1 = 5.5V; ISL33001 only (Note 11)
Full
-
2.1
4.0
mA
VCC1 = VCC2 = 5.5V; ISL33002 and ISL33003
(Note 11)
Full
-
2.0
3.0
mA
VCC2 = VCC1 = 5.5V; ISL33002 and ISL33003
(Note 11)
Full
-
0.22
0.6
mA
Supply Current from VCC2
ICC2
VCC1 Shut-down Supply
Current
ISHDN1
VCC2 Shut-down Supply
Current
ISHDN2
VCC1 = 5.5V, VEN = GND; ISL33001 only
Full
-
0.5
-
µA
VCC1 = VCC2 = 5.5V, VEN = GND; ISL33003 only
(Note 13)
Full
-
0.05
-
µA
VCC1 = VCC2 = 5.5V, VEN = GND, ISL33003 only
(Note 13)
Full
-
0.06
-
µA
SDA and SCL pins floating
Full
0.8
1
1.2
V
START-UP CIRCUITRY
Precharge Circuitry
Voltage
VPRE
Enable High Threshold
Voltage
VEN_H
+25
-
0.5*VCC
0.7*VCC
V
Enable Low Threshold
Voltage
VEN_L
+25
0.3*VCC
0.5*VCC
-
V
Enable from 0V to VCC1; ISL33001 and
ISL33003
Full
-1
0.1
1
µA
Enable Pin Input Current
IEN
Enable Delay, On-Off
tEN-HL
ISL33001 and ISL33003 (Note 10)
+25
-
10
-
ns
Enable Delay, Off-On
tEN-LH
ISL33001 and ISL33003 (Figure 3)
+25
-
86
-
µs
Bus Idle Time
tIDLE
(Figure 4, Note 12)
Full
50
83
150
µs
Ready Pin OFF State
Leakage Current
IOFF
ISL33001 only
+25
-1
0.1
1
µA
Ready Delay, On-Off
tREADY-HL
ISL33001 only (Note 10)
+25
-
10
-
ns
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FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Electrical Specifications
VEN = VCC1, VCC1 = +2.3V to +5.5V, VCC2 = +2.3V to +5.5V, unless otherwise noted (Note 8). Boldface limits apply
over the operating temperature range, -40°C to +85°C. (Continued)
PARAMETER
SYMBOL
CONDITIONS
TEMP
(°C)
MIN
(Note 9)
TYP
MAX
(Note 9)
UNITS
Ready Delay, Off-On
tREADY-LH
ISL33001 only (Note 10)
+25
-
10
-
ns
Ready Output Low Voltage
VOL_READY
VCC1 = +2.5V, IPULLUP = 3mA; ISL33001 only
Full
-
-
0.4
V
ITRAN_ACC
VCC1 = 2.7V, VCC2 = 2.7V ; (ACC = 0.7*VCC1 for
ISL33002 only) (Figure 8)
+25
-
5
-
mA
RISE-TIME ACCELERATORS
Transient Accelerator
Current
Accelerator Pin Enable
Threshold
VACC_EN
ISL33002 only
+25
-
0.5*VCC1
0.7*VCC1
V
Accelerator Pin Disable
Threshold
VACC_DIS
ISL33002 only
+25
0.3*VCC1
0.5*VCC1
-
V
IACC
ISL33002 only
+25
-1
0.1
1
µA
ISL33002 only (Note 10)
+25
-
10
-
ns
SDA, SCL I/O Pins
Human Body Model, SDA and SCL pins to ground
only (JESD22-A114)
+25
-
±12
-
kV
All Pins
Machine Model (JESD22-A115)
+25
-
±400
-
V
Class 3 HBM ESD (JESD22-A114)
+25
±6
-
kV
Accelerator Pin Input
Current
Accelerator Delay, On-Off
tPDOFF
ESD PROTECTION
INPUT-OUTPUT CONNECTIONS
Input Low Threshold
VIL
VCC1 = VCC2, 10kto VCC1 on SDA and SCL pins
+25
-
-
0.3*VCC1
V
Input-Output Offset
Voltage
VOS
VCC1 = 3.3V, 10kto VCC1 on SDA and SCL pins,
VINPUT = 0.2V; VCC2 = 3.3V, ISL33002 and
ISL33003 (Figure 5)
Full
0
50
150
mV
Output Low Voltage
VOL
VCC1 = 2.7V, VINPUT = 0V, ISINK = 3mA on
SDA/SCL pins; VCC2 = 2.7V, ISL33002 and
ISL33003 (Figure 6)
Full
-
-
0.4
V
Buffer SDA and SCL Pins
Input Capacitance
CIN
(Figure 25)
+25
-
10
-
pF
ILEAK
SDA and SCL pins = VCC1 = 5.5V;
VCC2 = 5.5V, ISL33002 and ISL33003
Full
-5
0.1
5
µA
SCL/SDA Propagation
Delay High-to-Low
tPHL
CLOAD = 100pF, 2.7kto VCC1 on SDA and SCL
pins, VCC1 = 3.3V; VCC2 = 3.3V, ISL33002 and
ISL33003 (Figure 7)
+25
0
27
100
ns
SCL/SDA Propagation
Delay Low-to-High
tPLH
CLOAD = 100pF, 2.7kto VCC1 on SDA and SCL
pins, VCC1 = 3.3V; VCC2 = 3.3V, ISL33002 and
ISL33003 (Figure 7)
+25
0
2
26
ns
Input Leakage Current
TIMING CHARACTERISTICS
NOTES:
8. The algebraic convention, whereby the most negative value is a minimum and the most positive a maximum, is used in this data sheet.
9. Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified. Temperature limits established by characterization
and are not production tested.
10. Typical value determined by design simulations. Parameter not tested.
11. Buffer is in the connected state.
12. ISL33002 and ISL33003 limits established by characterization. Not production tested.
13. If the VCC1 and VCC2 voltages diverge, then the shut down ICC increases on the higher voltage supply.
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FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Test Circuits and Waveforms
- VSDA_IN = VSDA_OUT = VSCL_OUT = VEN = VCC
- SDA_OUT and SCL pins connected to VCC
- Enable Delay Time Measured on ISL33001 only
- ISL33003 performance inferred from ISL33001
- If tDELAY1 < tEN-LH then tDELAY2 = tEN-LH + tIDLE + tREADY-LH
- If tDELAY1 > tEN-LH then tDELAY2 = tEN-LH + tREADY-LH
- EN Logic Input must be high for t > Enable Delay (tEN_LH)
prior to SCL_IN transition
- Bus Idle Time Measured on ISL33001 only
- ISL33002 and ISL33003 performance inferred from ISL33001
VEN
VCC
VCC
0.5*VCC
0V
VSDA_IN
VREADY
VCC
0.5*VCC
0.5*VCC
0.5VCC
VSCL_IN
0V
VCC
0V
0.5VCC
VREADY
0V
tDELAY1
tREADY-LH
tDELAY2
tIDLE
FIGURE 3. ENABLE DELAY TIME
FIGURE 4. BUS IDLE TIME
+3.3V
10kΩ
10kΩ
VCC1
SCL_OUT
10kΩ
SDA_OUT
0.2V
SCL_IN OR
SDA_IN
10kΩ
SDA_IN
SCL_IN
GND
VIN
0.2V
VO
SCL_OUT OR
SDA_OUT
VIN
0.2V
VOS = VO - 0.2V
FIGURE 5A. TEST CIRCUIT
FIGURE 5B. MEASUREMENT POINTS
FIGURE 5. INPUT TO OUTPUT OFFSET VOLTAGE
+2.7V
900Ω
900Ω
VCC1
SCL_OUT
900Ω
VCC1
SDA_OUT
900Ω
SCL_OUT
SDA_IN
SCL_IN
VOL
VCC1
GND
0V
0V
SDA_OUT
FIGURE 6A. TEST CIRCUIT
VOL
FIGURE 6B. MEASUREMENT POINTS
FIGURE 6. OUTPUT LOW VOLTAGE
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FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Test Circuits and Waveforms (Continued)
+3.3V
SCL_IN OR
SDA_IN
2.7kΩ
2.7kΩ
VCC1
SCL_OUT
2.7kΩ
SDA_OUT
2.7kΩ
SCL_OUT OR
SDA_OUT
SDA_IN
SCL_IN
GND
VIN
VIN
100pF
100pF
*tPLH
100pF
100pF
*tPHL
*Propagation delay measured between 50% of VCC1
FIGURE 7A. TEST CIRCUIT
FIGURE 7B. MEASUREMENT POINTS
FIGURE 7. PROPAGATION DELAY
ITRAN_ACC = CV/t
V/t is for only the accelerator
portion of the waveform
*V
VCC1
2.7kΩ
2.7kΩ
VCC1
SCL_OUT
SDA_OUT
SDA_IN
SCL_IN
GND
2nF
*V
VCC1
X
2.7kΩ
10kΩ
100kΩ
X
SCL_OUT
10kΩ
10kΩ
10kΩ
VCC1
SDA_OUT
SDA_IN
SCL_IN
GND
*V < V
X
CC1
(See Figure 22)
FIGURE 8. ACCELERATOR CURRENT TEST CIRCUIT
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FIGURE 9. ACCELERATOR PULSE WIDTH TEST CIRCUIT
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
SDA_IN
SDA_OUT
U1
M2
M1
U2
RISE TIME
ACCELERATOR
READY
ISL33001 ONLY
M5
LOGIC CONTROL
START-UP CIRCUITRY
VCC1
VCC2
ISL33002 AND ISL33003
EN
ISL33001 AND ISL33003
ACC
ISL33002 ONLY
PRECHARGE
CIRCUIT
SCL_IN
SCL_OUT
U3
M4
M3
U4
FIGURE 10. CIRCUIT BLOCK DIAGRAM
Application Information
The ISL33001, ISL33002, ISL33003 ICs are 2-Wire Bidirectional
Bus Buffers designed to drive heavy capacitive loads in
open-drain/open-collector systems. The ISL33001, ISL33002,
ISL33003 incorporate rise time accelerator circuitry that
improves the rise time for systems that use a passive pull-up
resistor for logic HIGH. These devices also feature hot swapping
circuitry for applications that require hot insertion of boards into
a host system (i.e., servers racks and I/O card modules). The
ISL33001 features a logic output flag (READY) that signals the
status of the buffer and an EN pin to enable or disable the buffer.
The ISL33002 features two separate supply pins for voltage level
shifting on the I/O pins and a logic input to disable the rise time
accelerator circuitry. The ISL33003 features an EN pin and the
level shifting functionality.
I2C and SMBUS Compatibility
The ISL33001, ISL33002, ISL33003 ICs are I2C and SMBUS
compatible devices, designed to work in open-drain/open-collector
bus environments. The ICs support both clock stretching and bus
arbitration on the SDA and SCL pins. They are designed to operate
from DC to more than 400kHz, supporting Fast Mode data rates of
the I2C specification.In addition, the buffer rise time accelerators
are designed to increase the capacitive drive capability of the bus.
With careful choosing of components, driving a bus with the I2C
specified maximum bus capacitance of 400pF at 400kHz data rate
is possible.
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Start-Up Sequencing and Hot Swap Circuitry
The ISL33001, ISL33002, ISL33003 buffers contain
undervoltage lock out (UVLO) circuitry that prevents operation of
the buffer until the IC receives the proper supply voltage. For
VCC1 and VCC2, this voltage is approximately 1.8V on the rising
edge of the supply voltage. Externally driven signals at the
SDA/SCL pins are ignored until the device supply voltage is
above 1.8V. This prevents communication errors on the bus until
the device is properly powered up. The UVLO circuitry is also
triggered on the falling edge when the supply voltage drops
below 1.7V.
Once the IC comes out of the UVLO state, the buffer remains
disconnected until it detects a valid connection state. A valid
connection state is either a BUS IDLE condition (see Figure 4) or a
STOP BIT condition (a rising edge on SDA_IN when SCL_IN is high)
along with the SCL_OUT and SDA_OUT pins being logic high.
Note: For the ISL33001 and ISL33003 with EN pins, after coming
out of UVLO, there will be an additional delay from the enable
circuitry if the EN pin voltage is not rising at the same time as the
supply pins (see Figure 3) before a valid connection state can be
established.
Coming out of UVLO but prior to a valid connection state, the SDA
and SCL pins are pre-charged to 1V to allow hot insertion.
Because the bus at any time can be between 0V and VCC,
pre-charging the I/O pins to 1V reduces the maximum
differential voltage from the buffer I/O pin and the active bus.
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
The pre-charge circuitry reduces system disturbance when the IC
is hot plugged into a live back plane that may have the bus
communicating with other devices.
performance. The rise time accelerators are only active on the
low-to-high transitions and provide an active constant current
source to slew the voltage on the pin quickly (Figure 21).
Note: For The ISL33001 and ISL33003 with EN pins, the
pre-charge circuitry is active only after coming out of UVLO and
having the device enabled.
The rise time accelerators are triggered immediately after the
buffer release threshold (approximately 30% of VCC) on both
sides of the buffer is crossed. Once triggered, the accelerators
are active for a defined pulse width (Figure 22) with the current
source turning off as it approaches the supply voltage.
Connection Circuitry
Once a valid connection condition is met, the buffer is active and
the input stage of the SDA/SCL pins is controlled by external
drivers. The output of the buffer will follow the input of the buffer.
The directionality of the IN/OUT pins are not exclusive
(bi-directional operation) and functionally behave identical to
each other. Being a two channel buffer, the SDA and SCL pins
also behave identically. In addition, the SDA and SCL portions of
the buffer are independent from each other. The SDA pins can be
driven in one direction while the SCL pins can be driven opposite.
Refer to Figure 10 for the operation of the bi-directional buffer.
When the input stage of the buffer on one side is driven low by an
external device, the output of the buffer drives an open-drain
transistor to pull the ‘output’ pin low. The ‘output’ pin will
continue to be held low by the transistor until the external driver
on the ‘input’ releases the bus.
To prevent the buffer from entering a latched condition where
both internal transistors are actively pulling the I/O pins low, the
buffer is designed to be active in only one direction. The buffer
logic circuitry senses, which input stage is being externally driven
low and sets that buffer to be the active one. For example,
referring to Figure 10, if SDA_OUT is externally driven low, buffer
U2 will be active and buffer U1 is inactive. M1 is turned on to
drive SDA_IN low, effectively buffering the signal from SDA_OUT
to SDA_IN. The low signal at the input of U1 will not turn M2 on
because U1 remains inactive, preventing a latch condition.
Buffer Output Low and Offset Voltage
By design, when a logic input low voltage is forced on the input of
the buffer, the output of the buffer will have an input to output
offset voltage. The output voltage of the buffer is determined by
Equation 1:
V OUT = V IN + V OS +  V CC /R PULL-UP  r ON 
(EQ. 1)
Where VOS is the buffer internal offset voltage, RPull-Up is the
pull-up resistance on the SDA/SCL pin to VCC and rON is the
ON-resistance of the buffer’s internal NMOS pull-down device.
The last term of the equation is the additional voltage drop
developed by sink current and the internal resistance of the
transistor. The VOS of the buffer can be determined by
Figures 19, 20 and is typically 40mV. Reducing the pull-up
resistor values increases the sink current and increases the
output voltage of the buffer for a given input low voltage
(Figures 17, through 20).
Rise Time Accelerators
The ISL33001, ISL33002, ISL33003 buffer rise time
accelerators on the SDA/SCL pins improve the transient
performance of the system. Heavy load capacitance or weak
pull-up resistors on an Open-Drain bus cause the rise time to be
excessively long, which leads to data errors or reduced data rate
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9
Enable Pin (ISL33001 and ISL33003)
When driven high, the enable pin puts the buffer into its normal
operating state. After power-up, EN high will activate the bus
pre-charge circuitry and wait for a valid connection state to
enable the buffer and the accelerator circuitry.
Driving the EN pin low disables the accelerators, disables the
buffer so that signals on one side of the buffer will be isolated
from the other side, disables the pre-charge circuit and places
the device in a low power shutdown state.
READY Logic Pin (ISL33001 Only)
The READY pin is a digital output flag for signaling the status of
the buffer. The pin is the drain of an Open-Drain NMOS. Connect
a resistor from the READY pin to VCC1 to provide the high pull-up.
The recommended value is 10kΩ.
When the buffer is disabled by having the EN pin low or if the
start-up sequencing is not complete, the READY pin will be pulled
low by the NMOS. When the buffer has the EN pin high and a
valid connection state is made at the SDA/SCL pins, the READY
pin will be pulled high by the pull-up resistor. The READY pin is
capable of sinking 3mA when pulled low while maintaining a
voltage of less than 0.4V.
ACC Accelerator Pin (ISL33002 Only)
The ACC logic pin controls the rise time accelerator circuitry of
the buffer. When ACC is driven high, the accelerators are enabled
and will be triggered when crossing the buffer release threshold.
When ACC is driven low, the accelerators are disabled.
For lightly loaded buses, having the accelerators active may
cause ringing or noise on the rising edge transition. Disabling the
accelerators will have the buffers continue to perform level
shifting with the VCC1 and VCC2 supplies and provide
capacitance buffering.
Propagation Delays
On a low-to-high transition, the rising edge signal is determined
by the bus pull-up resistor, load capacitance, and the accelerator
current from the ISL33001, ISL33002, ISL33003 buffer. Prior to
the accelerators becoming active, the buffer is connected and
the output voltage will track the input of the buffer. When the
accelerators activate the buffer connection is released and the
signal on each side of the buffer rises independently. The
accelerator current on both sides of the buffer will be equal. If the
pull-up resistance on both sides of the buffer are also equal, then
differences in the rise time will be proportional to the difference
in capacitive loading on the two sides.
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Because the signals on each side of the buffer rise
independently, the propagation delay can be positive or negative.
If the input side rises slowly relative to the output (i.e., heavy
capacitive loading on the input and light load on the output) then
the propagation delay tPLH is negative. If the output side rises
slowly relative to the input, tPLH is positive.
For high-to-low transitions, there is a finite propagation delay
through the buffer from the time an external low on the input
drives the NMOS output low. This propagation delay will always
be positive because the buffer connect threshold on the falling
edge is below the measurement points of the delay. In addition
to the propagation delay of the buffer, there will be additional
delay from the different capacitive loading of the buffer.
Figures 23 and 24 show how the propagation delay from high-tolow, tPHL, is affected by VCC and capacitive loading.
Pull-Up Resistor Selection
While the ISL33001, ISL33002, ISL33003 2-Channel buffers are
designed to improve the rise time of the bus in passive pull-up
systems, proper selection of the pull-up resistor is critical for
system operation when a buffer is used. For a bus that is
operating normally without active rise time circuitry, using the
ISL33001, ISL33002, ISL33003 buffer allows larger pull-up
resistor values to reduce sink currents when the bus is driving
low. However, choose a pull-up resistor value of no larger than
20kΩ regardless of the bus capacitance seen on the SDA/SCL
lines. The Bus Idle or Stop Bit condition requires valid logic high
voltages to give a valid connection state. Pull-up resistor values
20kΩ or smaller are recommended to overcome the typical
150kΩ impedance of the pre-charge circuitry, delivering valid
high levels.
The buffer’s propagation delay times for rising and falling edge
signals must be taken into consideration for the timing
requirements of the system. SETUP and HOLD times may need to
be adjusted to take into account excessively long propagation
delay times caused by heavy bus capacitances.
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10
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Typical Performance Curves
CIN = COUT = 10pF, VCC1 = VCC2 = VCC, TA = +25°C; Unless Otherwise Specified.
2.4
600
2.3
550
T = -40°C
2.2
2.0
T = +25°C
450
T = +85°C
1.9
ICC1 (nA)
ICC1 (mA)
500
T = +25°C
2.1
1.8
1.7
1.6
T = +85°C
400
350
300
250
1.5
200
1.4
150
1.3
1.2
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
100
6.0
2.0
2.5
3.0
3.5
4.0
VCC1 (V)
5.0
5.5
6.0
FIGURE 12. ICC1 DISABLED CURRENT vs VCC1 (ISL33001)
FIGURE 11. ICC1 ENABLED CURRENT vs VCC1 (ISL33001)
2.4
60
VCC2 = 5.5V
2.3
VCC2 = 5.5V
2.2
50
2.1
T = -40°C
T = +85°C
2.0
40
T = +25°C
1.9
ICC1 (nA)
ICC1 (mA)
4.5
VCC1 (V)
1.8
1.7
T = +25°C
30
1.6
T = +85°C
20
1.5
1.4
10
1.3
1.2
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
0
2.0
6.0
2.5
3.0
3.5
VCC1 (V)
4.0
4.5
5.0
5.5
6.0
VCC1 (V)
FIGURE 13. ICC1 ENABLED CURRENT vs VCC1 (ISL33002 AND
ISL33003)
FIGURE 14. ICC1 DISABLED CURRENT vs VCC1 (ISL33003)
60
0.24
T = +25°C
VCC1 = 5.5V
VCC1 = 5.5V
0.22
50
T = -40°C
40
T = +85°C
ICC2 (nA)
ICC2 (mA)
0.20
0.18
0.16
30
T = +25°C
T = +85°C
20
0.14
10
0.12
0.10
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VCC2 (V)
FIGURE 15. ICC2 ENABLED CURRENT vs VCC2 (ISL33002 AND
ISL33003)
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6.0
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
VCC2 (V)
FIGURE 16. ICC2 DISABLED CURRENT vs VCC2 (ISL33003)
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Typical Performance Curves (Continued)
CIN = COUT = 10pF, VCC1 = VCC2 = VCC, TA = +25°C; Unless Otherwise
120
120
VCC = 2.3V
100
100
80
80
T = -40°C
T = +25°C
60
VOL (mV)
VOL (mV)
T = +85°C
VCC = 2.7V
40
40
VCC = 4.5V
VIN = 0V
0
1
2
3
4
5
7
6
VCC = 3.3V
VIN = 0V
20
20
0
60
8
9
10
0
0
11
1
2
3
4
IOL (mA)
FIGURE 17. SDA/SCL OUTPUT LOW VOLTAGE vs SINK CURRENT vs VCC
90
VCC = 5.5V
80
80
70
70
60
60
50
VCC = 3.3V
VCC = 2.3V
40
VOS (mV)
VOS (mV)
8
9
10
11
100
90
20
20
0
1
2
3
4
5
6
IOL (mA)
7
8
9
10
0
11
VIN = 0.2V
0
1
2
3
4
5
6
7
8
9
10
11
IOL (mA)
FIGURE 20. INPUT TO OUTPUT OFFSET VOLTAGE vs SINK CURRENT
vs TEMPERATURE
800
11
ACCELERATOR PULSE WIDTH (ns)
12
T = -40°C
10
9
T = +85°C
7
6
5
T = +25°C
4
3
2.0
VCC = 3.3V
10
FIGURE 19. INPUT TO OUTPUT OFFSET VOLTAGE vs SINK CURRENT
vs VCC
8
T = +85°C
40
30
VIN = 0.2V
T = -40°C
T = +25°C
50
30
10
ACCELERATOR CURRENT (mA)
7
FIGURE 18. SDA/SCL OUTPUT LOW VOLTAGE vs SINK CURRENT vs
TEMPERATURE
100
0
5
6
IOL (mA)
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VCC (V)
FIGURE 21. ACCELERATOR PULL-UP CURRENT vs VCC
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6.0
700
See Figure 9
T = +25°C
600
T = -40°C
T = +85°C
500
400
300
200
2.0
2.5
3.0
3.5
4.0
4.5
VCC (V)
5.0
5.5
6.0
FIGURE 22. ACCELERATOR PULSE WIDTH vs VCC
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Typical Performance Curves (Continued)
50
40
T = +85°C
PROPAGATION DELAY (ns)
PROPAGATION DELAY (ns)
50
RPULL-UP = 2.7kΩ
CIN = 10pF
COUT = 100pF
T = +85°C
T = +25°C
30
20
T = -40°C
10
0
2.0
2.5
3.0
CIN = COUT = 10pF, VCC1 = VCC2 = VCC, TA = +25°C; Unless Otherwise
3.5
4.0
4.5
VCC (V)
5.0
5.5
40
30
T = +25°C
20
T = -40°C
VCC = 3.3V
RPULL-UP = 10kΩ
CIN = 50pF
10
0
0
6.0
FIGURE 23. PROPAGATION DELAY H-L vs VCC
100
200
300
400 500 600
COUT (pF)
700
800
900
FIGURE 24. PROPAGATION DELAY H-L vs COUT
Die Characteristics
12
11
SUBSTRATE AND TDFN THERMAL PAD POTENTIAL
(POWERED UP):
VCC = 2.3V
CAPACITANCE (pF)
VCC = 3.3V
GND
VCC = 5.5V
10
PROCESS:
0.25µm CMOS
9
8
7
6
-30
-10
10
30
50
70
90
TEMPERATURE (°C)
FIGURE 25. SDA/SCL PIN CAPACITANCE vs TEMPERATURE vs VCC
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in the quality certifications found at www.intersil.com/en/support/qualandreliability.html
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time
without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be
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FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Revision History
The revision history provided is for informational purposes only and is believed to be accurate, but not warranted. Please go to web to make sure you
have the latest revision.
DATE
REVISION
CHANGE
July 11, 2014
FN7560.6
In “Features” on page 1, changed “Low quiescent Current” from “2.2mA” to “2.1mA”.
On page 4, added “Pb-Free Reflow Profile” entry to “Thermal Info” section.
In “Electrical Spec” table on page 4, changed “VCC” to “VCC1” in the “Supply Current from VCC2” row.
In “Electrical Spec” table on page 5, for parameter “Input Low Threshold”, moved the “TYP” column
entry to the “MAX” column.
On page 6, Figure 4, clarified the associated notes.
On page 7, Figure 8, changed “IACC” to ITRAN_ACC”, and noted that the V/t is for the accelerator
portion of the waveform.
December 19, 2013
FN7560.5
Added Note 13 at the end of the "Elec Spec" table on page 5 as follows:
“13. If the Vcc1 and Vcc2 voltages diverge, then the shut-down Icc increases on the higher voltage
supply."
Added reference "(Note 13)" after "ISL33003 only" in rows for Vcc1 and Vcc2 "Shut-down Supply
current" parameters (last 2 rows of "Power Supplies" section) on page 4.
October 12, 2012
FN7560.4
Changed “SDA_IN, SCL_IN...0.3V to +(VCC1 + 0.3)V, SDA_OUT, SCL_OUT...0.3V to +(VCC2 + 0.3)V,
ENABLE, READY, ACC...0.3V to +(VCC1 + 0.3)V” to “SDA_IN, SCL_IN, SDA_OUT, SCL_OUT, READY...0.3V
to +7V; ENABLE, ACC...0.3V to +(VCC1 + 0.3)V”, in the Absolute Maximum Ratings section at the top of
page 4.
Removed “Pb-free Reflow Profile” and link from “Thermal Information” section at the top of page 4.
Added “open drain” and “Connect to 10kΩ pull-up resistor to VCC1.”, in Pin Descriptions in the READY
section on page 3.
October 11, 2011
FN7560.3
Converted to new datasheet template.
Changed Title of datasheet from: “2-Wire Bus Buffer With Rise Time Accelerators and Hot Swap
Capability”
to: I2C Bus Buffer with Rise Time Accelerators and Hot Swap Capability
Pg 1, added to Related Literature: AN1637, “Level Shifting Between 1.8V and 3.3V Using I2C Buffers”
Replaced POD M8.118 Rev 3 with Rev 4 due to the following changes:
Corrected lead width dimension in side view 1 from "0.25 - 0.036" to "0.25 - 0.36"
Replaced POD M8.15 Rev 1 with Rev 3 due to the following changes:
Changed in Typical Recommended Land Pattern the following:
2.41(0.095) to 2.20(0.087)
0.76 (0.030) to 0.60(0.023)
0.200 to 5.20(0.205)
Figure 3 (was Fig1) - Added:
- If tDELAY1 < tEN-LH then tDELAY2 = tEN-LH + tIDLE + tREADY-LH
- If tDELAY1 > tEN-LH then tDELAY2 = tEN-LH + tREADY-LH
and replaced graph
September 13, 2010
FN7560.2
Added SOIC package information to datasheet for ISL33001.
April 30, 2010
FN7560.1
Changed typical value of “Supply Current from VCC1” on page 4 for ISL33001 only from 2.2mA to
2.1mA.
Changed typical value of “Input-Output Offset Voltage” on page 5 from 100mV to 50mV.
March 18, 2010
FN7560.0
Initial Release.
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14
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Package Outline Drawing
L8.3x3H
8 LEAD THIN DUAL FLAT NO-LEAD PLASTIC PACKAGE (TDFN)
Rev 0, 2/08
2.38
1.50 REF
3.00
A
PIN #1 INDEX AREA
6 X 0.50
6
PIN 1
INDEX AREA
6
B
1
8 X 0.40
4
2.20
3.00
(4X)
1.64
0.15
5
8
0.10 M C A B
TOP VIEW
8 X 0.25
BOTTOM VIEW
( 2.38 )
SEE DETAIL "X"
0 .80 MAX
0.10 C
C
BASE PLANE
SEATING PLANE
0.08 C
2 . 80
( 2 .20 )
SIDE VIEW
( 1.64 )
C
0.2 REF
8X 0.60
0 . 00 MIN.
0 . 05 MAX.
( 8X 0.25 )
DETAIL “X”
( 6X 0 . 5 )
NOTES:
TYPICAL RECOMMENDED LAND PATTERN
1. Dimensions are in millimeters.
Dimensions in ( ) for Reference Only.
2. Dimensioning and tolerancing conform to AMSE Y14.5m-1994.
3. Unless otherwise specified, tolerance : Decimal ± 0.05
4. Lead width dimension applies to the metallized terminal and is
measured between 0.15mm and 0.30mm from the terminal tip.
5. Tiebar shown (if present) is a non-functional feature.
6. The configuration of the pin #1 identifier is optional, but must be
located within the zone indicated. The pin #1 identifier may be
either a mold or mark feature.
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15
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Package Outline Drawing
L8.3x3A
8 LEAD THIN DUAL FLAT NO-LEAD PLASTIC PACKAGE
Rev 4, 2/10
( 2.30)
3.00
( 1.95)
A
B
3.00
( 8X 0.50)
6
PIN 1
INDEX AREA
(4X)
(1.50)
( 2.90 )
0.15
PIN 1
TOP VIEW
(6x 0.65)
( 8 X 0.30)
TYPICAL RECOMMENDED LAND PATTERN
SEE DETAIL "X"
2X 1.950
6X 0.65
PIN #1
INDEX AREA
0.10 C
0.75 ±0.05
C
0.08 C
1
SIDE VIEW
6
1.50 ±0.10
8
8X 0.30 ±0.05
8X 0.30 ± 0.10
2.30 ±0.10
C
4
0.10 M C A B
0 . 2 REF
5
0 . 02 NOM.
0 . 05 MAX.
DETAIL "X"
BOTTOM VIEW
NOTES:
1.
Dimensions are in millimeters.
Dimensions in ( ) for Reference Only.
2.
Dimensioning and tolerancing conform to ASME Y14.5m-1994.
3.
Unless otherwise specified, tolerance : Decimal ± 0.05
4.
Dimension applies to the metallized terminal and is measured
between 0.15mm and 0.20mm from the terminal tip.
5.
Tiebar shown (if present) is a non-functional feature.
6.
The configuration of the pin #1 identifier is optional, but must be
located within the zone indicated. The pin #1 identifier may be
either a mold or mark feature.
7.
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16
Compliant to JEDEC MO-229 WEEC-2 except for the foot length.
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Package Outline Drawing
M8.118
8 LEAD MINI SMALL OUTLINE PLASTIC PACKAGE
Rev 4, 7/11
5
3.0±0.05
A
DETAIL "X"
D
8
1.10 MAX
SIDE VIEW 2
0.09 - 0.20
4.9±0.15
3.0±0.05
5
0.95 REF
PIN# 1 ID
1
2
B
0.65 BSC
GAUGE
PLANE
TOP VIEW
0.55 ± 0.15
0.25
3°±3°
0.85±010
H
DETAIL "X"
C
SEATING PLANE
0.25 - 0.36
0.08 M C A-B D
0.10 ± 0.05
0.10 C
SIDE VIEW 1
(5.80)
NOTES:
(4.40)
(3.00)
1. Dimensions are in millimeters.
(0.65)
(0.40)
(1.40)
TYPICAL RECOMMENDED LAND PATTERN
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17
2. Dimensioning and tolerancing conform to JEDEC MO-187-AA
and AMSEY14.5m-1994.
3. Plastic or metal protrusions of 0.15mm max per side are not
included.
4. Plastic interlead protrusions of 0.15mm max per side are not
included.
5. Dimensions are measured at Datum Plane "H".
6. Dimensions in ( ) are for reference only.
FN7560.6
July 11, 2014
ISL33001, ISL33002, ISL33003
Package Outline Drawing
M8.15
8 LEAD NARROW BODY SMALL OUTLINE PLASTIC PACKAGE
Rev 4, 1/12
DETAIL "A"
1.27 (0.050)
0.40 (0.016)
INDEX
6.20 (0.244)
5.80 (0.228)
AREA
0.50 (0.20)
x 45°
0.25 (0.01)
4.00 (0.157)
3.80 (0.150)
1
2
8°
0°
3
0.25 (0.010)
0.19 (0.008)
SIDE VIEW “B”
TOP VIEW
2.20 (0.087)
SEATING PLANE
5.00 (0.197)
4.80 (0.189)
1.75 (0.069)
1.35 (0.053)
1
8
2
7
0.60 (0.023)
1.27 (0.050)
3
6
4
5
-C-
1.27 (0.050)
0.51(0.020)
0.33(0.013)
SIDE VIEW “A
0.25(0.010)
0.10(0.004)
5.20(0.205)
TYPICAL RECOMMENDED LAND PATTERN
NOTES:
1. Dimensioning and tolerancing per ANSI Y14.5M-1994.
2. Package length does not include mold flash, protrusions or gate burrs.
Mold flash, protrusion and gate burrs shall not exceed 0.15mm (0.006
inch) per side.
3. Package width does not include interlead flash or protrusions. Interlead
flash and protrusions shall not exceed 0.25mm (0.010 inch) per side.
4. The chamfer on the body is optional. If it is not present, a visual index
feature must be located within the crosshatched area.
5. Terminal numbers are shown for reference only.
6. The lead width as measured 0.36mm (0.014 inch) or greater above the
seating plane, shall not exceed a maximum value of 0.61mm (0.024 inch).
7. Controlling dimension: MILLIMETER. Converted inch dimensions are not
necessarily exact.
8. This outline conforms to JEDEC publication MS-012-AA ISSUE C.
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18
FN7560.6
July 11, 2014
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