TI1 LMP8645HVMKX/NOPB Precision high voltage current sense amplifier Datasheet

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LMP8645, LMP8645HV
SNOSB29G – NOVEMBER 2009 – REVISED SEPTEMBER 2015
LMP8645, LMP8645HV Precision High Voltage Current Sense Amplifier
1 Features
3 Description
•
•
The LMP8645 and the LMP8645HV devices are
precision current sense amplifiers that detect small
differential voltages across a sense resistor in the
presence of high-input common-mode voltages.
1
•
•
•
•
•
•
•
•
•
•
Typical Values, TA = 25°C
High Common-Mode Voltage Range
– LMP8645 –2 V to 42 V
– LMP8645HV –2 V to 76 V
Supply Voltage Range 2.7 V to 12 V
Gain Configurable With a Single Resistor
Maximum Variable Gain Accuracy (With External
Resistor) 2%
Transconductance 200 μA/V
Low Offset Voltage 1 mV
Input Bias 12 μA
PSRR 90 dB
CMRR 95 dB
Temperature Range −40°C to 125°C
6-Pin SOT Package
Operating from a supply range of 2.7 V to 12 V, the
LMP8645 accepts input signals with a common-mode
voltage range of –2 V to 42 V, while the LMP8645HV
accepts input signals with a common-mode voltage
range of –2 V to 76 V. The LMP8645 and
LMP8645HV have adjustable gain for applications
where supply current and high common-mode voltage
are the determining factors. The gain is configured
with a single resistor, providing a high level of
flexibility, as well as accuracy as low as 2%
(maximum) including the gain setting resistor. The
output is buffered to provide low output impedance.
This high-side current sense amplifier is ideal for
sensing and monitoring currents in DC or batterypowered systems, has excellent AC and DC
specifications over temperature, and keeps errors in
the current sense loop to a minimum. The LMP8645
is an ideal choice for industrial, automotive, and
consumer applications, and is available in SOT-6
package.
2 Applications
•
•
•
•
•
•
High-Side Current Sense
Vehicle Current Measurement
Motor Controls
Battery Monitoring
Remote Sensing
Power Management
Device Information(1)
PART NUMBER
PACKAGE
LMP8645
SOT (6)
LMP8645HV
BODY SIZE (NOM)
1.60 mm × 2.90 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application
RS
IS
+
+IN
-IN
RIN
+
L
o
a
d
LMP8645
RIN
+
V
+
VA
ADC
VOUT
+
-
V
RG
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LMP8645, LMP8645HV
SNOSB29G – NOVEMBER 2009 – REVISED SEPTEMBER 2015
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
3
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
3
4
4
4
5
6
7
8
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
2.7-V Electrical Characteristics .................................
5-V Electrical Characteristics ....................................
12-V Electrical Characteristics ..................................
Typical Characteristics ..............................................
Detailed Description ............................................ 11
7.1 Overview ................................................................. 11
7.2 Functional Block Diagram ....................................... 12
7.3 Feature Description................................................. 12
7.4 Device Functional Modes........................................ 13
8
Application and Implementation ........................ 18
8.1 Application Information............................................ 18
8.2 Typical Applications ............................................... 18
9 Power Supply Recommendations...................... 21
10 Layout................................................................... 21
10.1 Layout Guidelines ................................................. 21
10.2 Layout Example .................................................... 21
11 Device and Documentation Support ................. 22
11.1
11.2
11.3
11.4
11.5
11.6
11.7
Device Support......................................................
Documentation Support ........................................
Related Links ........................................................
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
22
22
22
22
22
22
22
12 Mechanical, Packaging, and Orderable
Information ........................................................... 23
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision F (March 2013) to Revision G
•
Page
Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation
section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and
Mechanical, Packaging, and Orderable Information section. ................................................................................................. 1
Changes from Revision E (March 2013) to Revision F
•
2
Page
Changed layout of National Data Sheet to TI format ........................................................................................................... 19
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Copyright © 2009–2015, Texas Instruments Incorporated
Product Folder Links: LMP8645 LMP8645HV
LMP8645, LMP8645HV
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SNOSB29G – NOVEMBER 2009 – REVISED SEPTEMBER 2015
5 Pin Configuration and Functions
DD Package
6-Pin SOT
Top View
VOUT
V
-
+IN
1
LMP8645
LMP8645HV
2
3
+
6
V
5
RG
4
-IN
Pin Functions
PIN
NAME
NO.
I/O
DESCRIPTION
VOUT
1
O
Single-ended output
V-
2
P
Negative supply voltage
+IN
3
I
Positive input
-IN
4
I
Negative input
RG
5
I/O
+
6
P
V
External gain resistor
Positive supply voltage
6 Specifications
6.1 Absolute Maximum Ratings (1) (2) (3)
MAX
UNIT
Supply Voltage (VS = V+ - V−)
MIN
13.2
V
Differential voltage +IN- (-IN)
6
V
80
V
Voltage at pins +IN, -IN
LMP8645HV
–6
LMP8645
–6
Voltage at RG pin
V-
Voltage at OUT pin
Junction temperature
(4)
Storage temperature, Tstg
(1)
(2)
(3)
(4)
–65
60
V
13.2
V
V+
V
150
°C
150
°C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
For soldering specifications, refer to SNOA549
The maximum power dissipation must be derated at elevated temperatures and is dictated by TJ(MAX), RθJA, and the ambient
temperature, TA. The maximum allowable power dissipation PDMAX = (TJ(MAX) - TA)/ RθJA or the number given in Absolute Maximum
Ratings, whichever is lower.
Copyright © 2009–2015, Texas Instruments Incorporated
Product Folder Links: LMP8645 LMP8645HV
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6.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
(3)
Electrostatic
discharge
Human body model (HBM), per
ANSI/ESDA/JEDEC JS-001 (1) (2)
All pins except 3 and 4
±2000
Pins 3 and 4
±5000
Charged-device model (CDM), per JEDEC specification JESD22-C101 (3)
±1250
Machine Model
±200
UNIT
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
Human Body Model, applicable std. MIL-STD-883, Method 3015.7. Machine Model, applicable std. JESD22-A115-A (ESD MM std. of
JEDEC) Field-Induced Charge-Device Model, applicable std. JESD22-C101-C (ESD FICDM std. of JEDEC).
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
MIN
MAX
Supply voltage (VS = V+ – V−)
2.7
12
V
Temperature range (1)
–40
125
°C
(1)
UNIT
The maximum power dissipation must be derated at elevated temperatures and is dictated by TJ(MAX), RθJA, and the ambient
temperature, TA. The maximum allowable power dissipation PDMAX = (TJ(MAX) - TA)/ RθJA or the number given in Absolute Maximum
Ratings, whichever is lower.
6.4 Thermal Information
LMV8645,
LMV8645HV
THERMAL METRIC (1)
DDC (SOT)
UNIT
6 PINS
RθJA
(1)
(2)
4
Junction-to-ambient thermal resistance (2)
96
°C/W
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report, SPRA953.
The maximum power dissipation must be derated at elevated temperatures and is dictated by TJ(MAX), RθJA, and the ambient
temperature, TA. The maximum allowable power dissipation PDMAX = (TJ(MAX) - TA)/ RθJA or the number given in Absolute Maximum
Ratings, whichever is lower.
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Product Folder Links: LMP8645 LMP8645HV
LMP8645, LMP8645HV
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SNOSB29G – NOVEMBER 2009 – REVISED SEPTEMBER 2015
6.5 2.7-V Electrical Characteristics
Unless otherwise specified, all limits specified for at TA = 25°C, VS = V+ – V–, V+ = 2.7 V, V− = 0 V, −2 V < VCM < 76 V, RG =
25 kΩ, RL = 10 MΩ. (1)
PARAMETER
VOS
TEST CONDITIONS
Input Offset Voltage
TCVOS
VCM = 2.1 V
Input Offset Voltage Drift (4)
(5)
Input Bias Current (6)
IB
eni
Input Voltage Noise
VSENSE(M
(5)
AX)
Gain AV
Gm
Gm drift (5)
−40°C to 125°C, VCM = 2.1 V
1
At the temperature extremes
+
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
140 ppm /°C
95
–2 V <VCM < 2 V
60
dB
dB
RG = 10 kΩ, CG = 4 pF VSENSE = 400 mV,
CL = 30 pF , RL = 1 MΩ
990
RG = 25 kΩ, CG = 4 pF, VSENSE = 200 mV,
CL = 30 pF, RL = 1 MΩ
260
Rg = 50 kΩ, CG = 4 pF, VSENSE = 100 mV,
CL = 30 pF, RL = 1 MΩ
135
VCM = 5 V, CG = 4 pF, VSENSE from 25 mV
to 175 mV, CL = 30 pF, RL = 1 MΩ
0.5
VCM = 2.1 V
Max Output Capacitance
Load (5)
2%
3.4%
LMP8645HV 2.1 V < VCM < 76 V
LMP8645 2.1 V < VCM< 42 V
Minimum Output Voltage
CLOAD
–2%
90
VCM = 2.1 V, Rg = 500 kΩ
V/V
µA/V
–3.4%
VCM = 2.1 V, 2.7 V < V < 12 V
Maximum Output Voltage
Output current (5)
100
200
VCM = –2 V
IOUT
μA
mV
Supply Current
VOUT
20
600
VCM = 2.1 V
IS
μV/°C
VCM = 12 V, RG = 5 kΩ
VCM = 2.1 V
Slew Rate (8) (5)
SR
7
nV/√Hz
Accuracy
Common-Mode Rejection
Ratio
mV
120
VCM = 2.1 V
−3-dB Bandwidth (5)
1.7
UNIT
f > 10 kHz, RG = 5 kΩ
VCM = 12 V
CMRR
BW
–1.7
12
Transconductance
PSRR
MAX (2)
1
VCM = 2.1 V
Adjustable Gain Setting (7)
Power Supply Rejection
Ratio
TYP (3)
–1
VCM = 2.1 V
(5)
Max Input Sense Voltage
At the temperature extremes
MIN (2)
kHz
V/µs
380
525
2000
2500
At the temperature extremes
710
At the temperature extremes
uA
2700
1.2
V
20
Sourcing, VOUT = 600 mV, Rg = 150 kΩ
5
Sinking, VOUT = 600 mV, Rg = 150 kΩ
5
30
mV
mA
pF
Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device such that TJ = TA. No specification of parametric performance is indicated in the electrical tables under
conditions of internal self-heating where TJ > TA.
All limits are specified by testing, design, or statistical analysis.
Typical values represent the most likely parametric norm at the time of characterization. Actual typical values may vary over time and
will also depend on the application and configuration. The typical values are not tested and are not ensured on shipped production
material.
Offset voltage temperature drift is determined by dividing the change in VOS at the temperature extremes by the total temperature
change.
This parameter is specified by design and/or characterization and is not tested in production.
Positive Bias Current corresponds to current flowing into the device.
This parameter is specified by design and/or characterization and is not tested in production.
The number specified is the average of rising and falling slew rates and measured at 90% to 10%.
Copyright © 2009–2015, Texas Instruments Incorporated
Product Folder Links: LMP8645 LMP8645HV
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6.6 5-V Electrical Characteristics
Unless otherwise specified, all limits specified for at TA = 25°C, VS = V+ – V–, V+ = 5 V, V− = 0 V, −2 V < VCM < 76 V, Rg = 25
kΩ, RL = 10 MΩ. (1)
PARAMETER
MIN (2)
TEST CONDITIONS
TYP (3)
MAX (2)
–1
1
–1.7
1.7
UNIT
VOS
Input Offset Voltage
VCM = 2.1 V
TCVOS
Input Offset Voltage
Drift (4) (5)
VCM = 2.1 V
IB
Input Bias Current (6)
VCM = 2.1 V
12.5
f > 10 kHz, RG = 5 kΩ
120
nV/√Hz
VCM = 12 V, RG = 5 kΩ
600
mV
eni
Input Voltage Noise
VSENSE(M
(5)
Max Input Sense Voltage
(5)
AX)
Gain AV
Gm
Adjustable Gain Setting (5)
VCM = 12 V
Transconductance
VCM = 2.1 V
Accuracy
VCM = 2.1 V
Gm drift (5)
−40°C to 125°C, VCM = 2.1 V
PSRR
Power Supply Rejection
Ratio
CMRR
Common-Mode Rejection
Ratio
−3-dB Bandwidth (5)
BW
Slew Rate (7) (5)
SR
At the temperature extremes
1
-2 V < VCM < 2 V
60
(1)
(2)
(3)
(4)
(5)
(6)
(7)
6
dB
850
RG= 25 kΩ, CG = 4 pF, VSENSE = 300 mV,
CL = 30 pF, RL = 1 MΩ
260
RG= 50 kΩ, CG = 4 pF, VSENSE = 300 mV,
CL = 30 pF, RL = 1 MΩ
140
VCM = 5 V, CG = 4 pF, VSENSE from 100 mV
to 500 mV, CL = 30 pF, RL= 1 MΩ
0.5
VCM = 2.1 V
Max Output Capacitance
Load (5)
dB
RG= 10 kΩ, CG = 4 pF, VSENSE = 400 mV,
CL = 30 pF, RL = 1 MΩ
Minimum Output Voltage
V/V
µA/V
2%
95
VCM = 5 V, Rg = 500 kΩ
CLOAD
100
3.4%
LMP8645HV 2.1 V < VCM < 76 V
LMP8645 2.1 V < VCM < 42 V
Maximum Output Voltage
Output current (5)
μA
–2%
90
VCM = −2 V
IOUT
22
–3.4%
VCM = 2.1 V, 2.7 V < V < 12 V
Supply Current
VOUT
μV/°C
140 ppm /°C
+
VCM = 2.1 V
IS
7
200
At the temperature extremes
mV
kHz
V/µs
450
610
2100
2800
At the temperature extremes
780
At the temperature extremes
uA
3030
3.3
V
22
Sourcing, VOUT = 1.65 V, Rg = 150 kΩ
5
Sinking, VOUT = 1.65 V, Rg = 150 kΩ
5
30
mV
mA
pF
Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device such that TJ = TA. No specification of parametric performance is indicated in the electrical tables under
conditions of internal self-heating where TJ > TA.
All limits are specified by testing, design, or statistical analysis.
Typical values represent the most likely parametric norm at the time of characterization. Actual typical values may vary over time and
will also depend on the application and configuration. The typical values are not tested and are not ensured on shipped production
material.
Offset voltage temperature drift is determined by dividing the change in VOS at the temperature extremes by the total temperature
change.
This parameter is specified by design and/or characterization and is not tested in production.
Positive Bias Current corresponds to current flowing into the device.
The number specified is the average of rising and falling slew rates and measured at 90% to 10%.
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Copyright © 2009–2015, Texas Instruments Incorporated
Product Folder Links: LMP8645 LMP8645HV
LMP8645, LMP8645HV
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SNOSB29G – NOVEMBER 2009 – REVISED SEPTEMBER 2015
6.7 12-V Electrical Characteristics
Unless otherwise specified, all limits specified for at TA = 25°C, VS = V+ – V-, V+ = 12 V, V− = 0 V, −2 V < VCM < 76 V, Rg= 25
kΩ, RL = 10 MΩ. (1)
PARAMETER
TEST CONDITIONS
VOS
Input Offset Voltage
VCM = 2.1 V
TCVOS
Input Offset Voltage
Drift (4) (5)
VCM = 2.1 V
IB
Input Bias Current (6)
VCM = 2.1 V
eni
Input Voltage Noise
VSENSE(M
(5)
Max Input Sense Voltage
(5)
AX)
Gain AV
Gm
−40°C to 125°C, VCM = 2.1 V
1
At the temperature extremes
+
60
(1)
(2)
(3)
(4)
(5)
(6)
(7)
dB
dB
RG = 10 kΩ, CG = 4 pF, VSENSE = 400 mV,
CL = 30 pF, RL = 1 MΩ
860
RG = 25 kΩ, CG = 4 pF, VSENSE = 400 mV,
CL = 30 pF, RL = 1 MΩ
260
RG = 50 kΩ, CG = 4 pF, VSENSE = 400 mV,
CL = 30 pF, RL = 1 MΩ
140
VCM = 5 V, CG = 4 pF, VSENSE from 100 mV
to 500 mV, CL = 30 pF, RL = 1 MΩ
0.6
VCM = 2.1 V
V/V
µA/V
140 ppm /°C
–2 V < VCM < 2 V
Minimum Output Voltage
Max Output Capacitance
Load (5)
100
2%
95
VCM = 12 V, RG= 500 kΩ
CLOAD
μA
3.4%
LMP8645HV 2.1 V < VCM < 76 V
LMP8645 2.1 V < VCM< 42 V
Maximum Output Voltage
Output current (5)
23
–2%
90
VCM = −2 V
IOUT
μV/°C
–3.4%
VCM = 2.1 V, 2.7 V <V < 12 V
Supply Current
VOUT
7
200
VCM = 2.1 V
IS
mV
mV
Gm drift (5)
(5)
1.7
600
VCM = 2.1 V
Slew Rate (7)
SR
–1.7
UNIT
VCM = 12 V, RG = 5 kΩ
Accuracy
−3-dB Bandwidth (5)
1
nV/√Hz
VCM = 2.1 V
Common-Mode Rejection
Ratio
–1
120
VCM = 12 V
CMRR
MAX (2)
f > 10 kHz, RG = 5 kΩ
Transconductance
PSRR
TYP (3)
13
Adjustable Gain Setting (5)
Power Supply Rejection
Ratio
BW
At the temperature extremes
MIN (2)
kHz
V/µs
555
765
2200
2900
At the temperature extremes
920
At the temperature extremes
uA
3110
10.2
V
24
Sourcing, VOUT = 5.25 V, Rg = 150 kΩ
5
Sinking, VOUT = 5.25 V, Rg = 150 kΩ
5
30
mV
mA
pF
Electrical Table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device such that TJ = TA. No specification of parametric performance is indicated in the electrical tables under
conditions of internal self-heating where TJ > TA.
All limits are specified by testing, design, or statistical analysis.
Typical values represent the most likely parametric norm at the time of characterization. Actual typical values may vary over time and
will also depend on the application and configuration. The typical values are not tested and are not ensured on shipped production
material.
Offset voltage temperature drift is determined by dividing the change in VOS at the temperature extremes by the total temperature
change.
This parameter is specified by design and/or characterization and is not tested in production.
Positive Bias Current corresponds to current flowing into the device.
The number specified is the average of rising and falling slew rates and measured at 90% to 10%.
Copyright © 2009–2015, Texas Instruments Incorporated
Product Folder Links: LMP8645 LMP8645HV
Submit Documentation Feedback
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LMP8645, LMP8645HV
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6.8 Typical Characteristics
Unless otherwise specified: TA = 25°C, VS= V+– V–, VSENSE= +IN – (–IN), RL = 10 MΩ.
2300
2300
2100
VCM = -2V
2400
2200
2100
1900
1800
-40°C
800
25°C
125°C
1500
VS = 12V
1300
VS = 5V
1100
VCM = 2.1V
700
600
500
400
300
1700
IS (µA)
IS (µA)
2000
1900
2.7
5.3
8.0
10.6
VS = 2.7V
900
700
500
300
13.2
-2 -1 0
1
2
VS (V)
Figure 1. Supply Current vs. Supply Voltage
4 16 28 40 52 64 76
Figure 2. Supply Current vs. VCM
110
100
VS = 5V, Rg = 10 kΩ
VCM = 5V, Rg = 10 k:
90
CMRR (dB)
80
PSRR (dB)
3
VCM (V)
60
70
50
40
30
20
1
10
100
1k
10k
10
100k
1
10
FREQUENCY (Hz)
25
150
CMRR (dB)
GAIN (dB)
Rg = 10 k:
5
0
100
1M
VS = 12V
25°C
110
125°C
90
70
1k
10k
100k
1M
10M
50
-2
11
FREQUENCY (Hz)
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24
37
50
63
76
VCM (V)
Figure 6. CMRR vs. VCM
Figure 5. Gain vs. Frequency
8
100k
130
Rg = 50 k:
15
10
10k
-40°C
VS = 5V, VCM = 5V
Rg = 25 k:
1k
Figure 4. AC CMRR vs. Frequency
Figure 3. AC PSRR vs. Frequency
20
100
FREQUENCY (Hz)
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SNOSB29G – NOVEMBER 2009 – REVISED SEPTEMBER 2015
Typical Characteristics (continued)
Unless otherwise specified: TA = 25°C, VS= V+– V–, VSENSE= +IN – (–IN), RL = 10 MΩ.
40
4.0
VS = 5V, VCM = 12V
3.0
30
Rg = 25 k:
Rg = 50 k:
2.0
1.5
Rg = 10 k:
Rg=25 kΩ
25
VOUT (mV)
Rg=50 kΩ
20
15
1.0
10
0.5
5
VS = 5V, VCM = 12V
200
300
400
500
0
600
-5
0
5
10
VSENSE (mV)
VSENSE (mV)
Rg = 25 kÖ
VOUT (40 mV/div)
VS = 12V, VCM = 5V
VSENSE (100 mV/div)
VOUT (400 mV/div)
VS=12V, VCM=5V
Rg = 50 kÖ
VSENSE
Rg = 50 kÖ
Rg = 25 kÖ
Rg = 10 kÖ
Rg = 10 kÖ
TIME (4 és/div)
TIME (4 és/div)
Figure 9. Large Step Response
Figure 10. Small Step Response
VS = 12V, VCM = 5V
VS = 12V, VCM = 5V
Rg = 25 kÖ
VOUT (40 mV/div)
Rg = 50 kÖ
VSENSE (10 mV/DIV)
VOUT (40 mV/DIV)
VSENSE
VSENSE
20
Figure 8. Output Voltage vs. VSENSE (ZOOM Close to 0 V)
Figure 7. Output Voltage vs. VSENSE
VSENSE
15
VSENSE (10 mV/div)
100
Rg = 50 kÖ
Rg = 25 kÖ
VSENSE (10 mV/div)
VOUT (V)
2.5
0.0
0
Rg=10 kΩ
35
3.5
Rg = 10 kÖ
Rg = 10 kÖ
TIME (800 ns/DIV)
TIME (800 ns/div)
Figure 11. Settling Time (Rise)
Figure 12. Settling Time (Fall)
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Typical Characteristics (continued)
Unless otherwise specified: TA = 25°C, VS= V+– V–, VSENSE= +IN – (–IN), RL = 10 MΩ.
VS = 12V
VOUT
TIME (4 és/DIV)
TIME (4 és/DIV)
Figure 13. Common-Mode Step Response (Rise)
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VCM (20V/DIV)
VOUT
VCM
VOUT (100 mV/DIV)
VCM
VCM (20V/DIV)
VOUT (50 mV/DIV)
VS = 12V
Figure 14. Common-Mode Step Response (Fall)
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7 Detailed Description
7.1 Overview
Operating from a 2.7-V to 12-V supply range, the LMP8645 accepts input signals with a common-mode voltage
range of –2 V to 42 V, while the LMP8645HV accepts input signals with a common-mode voltage range of –2 V
to 76 V. The LMP8645 and LMP8645HV have adjustable gain, set by a single resistor, for applications where
supply current and high common-mode voltage are the determining factors.
7.1.1 Theory of Operation
RIN = 1/Gm
VSENSE
IS
RS
+
+IN
-IN
RIN+
+
LMP8645
RIN-
L
o
a
d
-
+
V
•
IS
VOUT
+
-
RG
V
RGAIN
Figure 15. Current Monitor Example Circuit
As seen in Figure 15, the current flowing through the shunt resistor ( RS) develops a voltage drop equal to
VSENSE across RS. The resulting voltage at the –IN pin will now be less than +IN pin proportional to the VSENSE
voltage.
The sense amplifier senses this indifference and increases the gate drive to the MOSFET to increase IS′ current
flowing through the RIN+ string until the amplifer inputs are equal. In this way, the voltage drop across RIN+ now
matches the votlage drop across VSENSE.
The RIN resistors are trimmed to a nominal value of 5 kΩ each. The current IS′ flows through RIN+ , the MOSFET,
and RGAIN to ground. The IS′ current generates the voltage VG across RGAIN. The gain is created bythe ratio of
RGAIN and RIN.
A current proportional to IS is generated according to the following relation:
IS′ = VSENSE / RIN = RS × IS / RIN
where
•
RIN = 1 / Gm
(1)
This current flows entirely in the external gain resistor developing a voltage drop equal to:
VG = IS′ × RGAIN = (VSENSE / RIN) × RGAIN = ( (RS × IS) / RIN ) × RGAIN
(2)
This voltage is buffered and presented at the output with a very low output impedance allowing a very easy
interface to other devices (ADC, μC…).
VOUT = (RS × IS) × G
where
•
G = RGAIN / RIN
(3)
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7.2 Functional Block Diagram
+IN
-IN
RIN
+
RIN
LMP8645
LMP8645HV
-
+
V
-
VOUT
+
RG
V
-
7.3 Feature Description
7.3.1 Driving ADC
The input stage of an Analog-to-Digital converter can be modeled with a resistor and a capacitance versus
ground. So if the voltage source does not have a low impedance, an error in the measurement of the amplitude
will occur. In this condition a buffer is needed to drive the ADC. The LMP8645 has an internal output buffer able
to drive a capacitance load up to 30 pF or the input stage of an ADC. If required an external lowpass RC filter
can be added at the output of the LMP8645 to reduce the noise and the bandwidth of the current sense. Any
other filter solution that implies a capacitance connected to the RG pin is not suggested due to the high
impedance of that pin.
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Feature Description (continued)
RS
IS
+
+IN
-IN
L
o
a
d
RIN
+
RIN
LMP8645
-
+
V
+
VA
-
RF
ADC
+
RG
VOUT
V
RGAIN
-
CF
f-3dB = 1/(2SRFCF)
Figure 16. LMP8645 to ADC Interface
7.3.2 Applying Input Voltage With No Supply Voltage
The full specified input common-mode voltage range may be applied to the inputs while the LMP8645 power is
off (V+ = 0 V). When the LMP8640 is powered off, the RIN resistors are disconnected internally by MOSFETS
and the leakage currents are very low (sub µA).
The 6-V input differential limit still applies, so at no time should the two inputs be more than 6-V apart. There are
also Zener clamps on the inputs to ground, so do not exceed the input limits specified in the Absolute Maximum
Ratings (8) (9) (10).
7.4 Device Functional Modes
7.4.1 Selection of the Gain Resistor
For the LMP8645 and LMP8645HV, the gain is selected through an external gain set resistor connected to the
RG pin. Moreover, the gain resistor RGAIN determines the voltage of the output buffer, which is related to the
supply voltage and also to the common-mode voltage of the input signal.
7.4.2 Gain Range Limitations
The gain resistor must be chosen such that the theoretical maximum output voltage does not exceed the
LMP8645 maximum output voltage rating for a given common-mode voltage. These limits are due to the internal
amplifier bias point and the VCM headroom required to generate the required currents across the RIN and RGAIN
resistors.
The following sections explain how to select the gain resistor for various ranges of the input common-mode
voltage.
7.4.2.1 Range 1: VCM is –2 V to 1.8 V
The maximum voltage at the RG pin is given by the following inequality:
VRG = Vsense × RGAIN × Gm ≤ min (1.3 V; Vout_max)
where
•
Vout_max is the maximum allowable output voltage according to the Electrical Tables
(4)
(8)
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(9) If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
(10) For soldering specifications, refer to SNOA549
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Device Functional Modes (continued)
All the gain resistors (RGAIN) values which respect the previous inequality are allowed. The graphical
representation of Figure 17 helps in the selection.
All the combinations (VSENSE , RGAIN) below the curve are allowed.
Rg (kÖ)
VS = 5V, VS = 12V
50
10
GAIN (V/V)
100
500
VS = 2.7V
1
5
0
100
200
300
400
500
Vsense (mV)
Figure 17. Allowed Gains for Range 1
As a consequence, once selected, the gain (RGAIN) and the VSENSE range is fixed, too.
For example if an application required a Gain of 10, RG will be 50 kΩ and VSENSE will be in the range 10 mV to
100 mV.
7.4.2.2 Range 2: VCM is 1.8 V to VS
In this range, the maximum voltage at the RG pin is related to the common-mode voltage and VSENSE. So all the
RGAIN resistor values which respect the following inequalities are allowed:
VRG ≤ min (Vout_max; (VCM – Vsense– 250 mV))
where
•
•
VRG = VSENSE * RGAIN * Gm
Vout_max is the maximum allowable output voltage according to the 2.7-V Electrical Characteristics, 5-V
Electrical Characteristics, and 12-V Electrical Characteristics.
(5)
The graphical representation in Figure 18 helps in the selection.
All the combinations (VSENSE, RGAIN) below the curves for given VCM and supply voltage are allowed.
100
500
Vs=12V @ VCM=6V
10
50
Gain (V/V)
Rg (k:)
Vs=5V @ VCM=2.5V
Vs=2.7V @ VCM=2V
5
0
100
200
300
400
1
500
Vsense (mV)
Figure 18. Allowed Gains for Range 2
Also in this range, once selected, the RGAIN (Gain) and the VSENSE range is fixed too.
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Device Functional Modes (continued)
7.4.2.3 Range 3: VCM is greater than VS
The maximum voltage at the RG pin is Vout_max, it means that:
VOUT = VSENSE × RGAIN / RIN ≤ Vout_max
where
•
Vout_max is the maximum allowable output voltage according to the Electrical Tables
(6)
So all the RGAIN resistors which respect the previous inequality are allowed. The graphical representation in
Figure 19 helps with the selection.
All the combinations (VSENSE, RGAIN) below the curves are allowed.
100
500
Rg (k:)
Vs=5V
10
50
Gain (V/V)
Vs=12V
Vs=2.7V
5
0
100
200
300
400
1
500
Vsense (mV)
Figure 19. Allowed Gains for Range 3
Also in this range once selected the RGAIN (Gain) the VSENSE range is fixed too.
From the ranges shown above, a good way to maximize the output voltage swing of the LMP8645 is to select the
maximum allowable RGAIN according to the previous equations. For a fixed supply voltage and VSENSE as the
common-mode voltage increases, the maximum allowable RGAIN increases too.
7.4.3 Selection of Sense Resistor
The accuracy of the current measurement highly depends on the value of the shunt resistor RS. Its value
depends on the application and it is a compromise between small-signal accuracy and maximum permissible
voltage (and power) loss in the sense resistor. High values of RS provide better accuracy at lower currents by
minimizing the effects of amplifier offset. Low values of RS minimize voltage and power loss in the supply section,
but at the expense of low current accuracy. For most applications, best performance is obtained with an RS value
that provides a full-scale shunt voltage range of 100 mV to 200 mV.
In applications where a small current is sensed, a larger value of RS is selected to minimize the error in the
proportional output voltage. Higher resistor value improves the signal-to-noise ratio (SNR) at the input of the
current sense amplifier and hence gives a more accurate output.
Similarly when high current is sensed, the power losses in RS can be significant so a smaller value of RS is
desired. In this condition it is also required to take in account also the power rating of RS resistor. The low input
offset and customizable gain of the LMP8645 allows the use of small sense resistors to reduce power dissipation
still providing a good input dynamic range. The input dynamic range is the ratio between the maximum signal
that can be measured and the minimum signal that can be detected, where usually the input offset and amplifier
noise are the principal limiting factors.
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Device Functional Modes (continued)
Figure 20. Example of a Kelvin (4-Wire) Connection to a Two-Terminal Resistor
The amplifier inputs should be directly connected to the sense resistor pads using Kelvin or 4-wire connection
techniques. The paths of the input traces should be identical, including connectors and vias, so that these errors
will be equal and cancel.
7.4.3.1 Resistor Power Rating and Thermal Issues
The power dissipated by the sense resistor can be calculated from:
PD = IMAX2 * RS
where
•
•
•
PD is the power dissipated by the resistor in Watts
IMAX is the maximum load current in A
RS is the sense resistor value in Ω.
(7)
The resistor must be rated for more than the expected maximum power (PD), with margin for temperature
derating. Be sure to observe any power derating curves provided by the resistor manufacturer.
Running the resistor at higher temperatures will also affect the accuracy. As the resistor heats up, the resistance
generally goes up, which will cause a change in the measurement. The sense resistor should have as much
heat-sinking as possible to remove this heat through the use of heatsinks or large copper areas coupled to the
resistor pads. A reading drifting slightly after turnon can usually be traced back to sense resistor heating.
7.4.3.2 Using PCB Trace as a Sense Resistor
While it may be tempting to use the resistance of a known area of PCB trace or copper area as a sense resistor,
TI does not recommend this for precision measurements.
The tempco of copper is typically 3300 to 4000 ppm/°K (0.33% to 0.4% per °C), which can vary with PCB
processes.
A typical surface mount sense resistor temperature coefficient (tempco) is in the 50 ppm to 500 ppm per °C
range offering more measurement consistency and accuracy over the copper trace. Special low tempco resistors
are available in a range from 0.1 ppm to 50 ppm, but at a much higher cost.
7.4.4 Sense Line Inputs
The sense lines should be connected to a point on the resistor that is not shared with the main current path, as
shown in Figure 20. For lowest drift, the amplifier must be mounted away from any heat generating devices,
which may include the sense resistor. The traces should be one continuous trace of copper from the sense
resistor pad to the amplifier input pin pad, and ideally on the same copper layer with minimal vias or connectors.
This can be important around the sense resistor if it is generating any significant heat gradients. Vias in the
sense lines should be formed from continuous plated copper and routing through mating connectors or headers
should be avoided. It is better to extend the sense lines than to place the amplifier in a hostile environment.
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Device Functional Modes (continued)
To minimize noise pickup and thermal errors, the input traces should be treated like a high-speed differential
signal pair and routed tightly together with a direct path to the input pins on the same copper layer. They do not
need to be impedance matched, but should follow the same matching rules about vias, spacing and equal
lengths. The input traces should be run away from noise sources, such as digital lines, switching supplies, or
motor drive lines.
Remember that these input traces can contain high voltage (up to 76 V), and should have the appropriate trace
routing clearances to other components, traces and layers. Because the sense traces only carry the amplifier
bias current, the connecting input traces can be thin traces running close together. This can help with routing or
creating the required spacings.
NOTE
Due to the nature of the device topology, the positive input bias current will vary with
VSENSE with an extra current approximately equivalent to VSENSE / 5 kΩ on top of the
typical 12 uA bias current.
The negative input bias current is not in the feedback path and will not change over VSENSE. High or missmatched source impedances should be avoided as this imbalance will create an additional error term over input
voltage.
7.4.4.1 Effects of Series Resistance on Sense Lines
While the sense amplifier is depicted as a conventional operational amplifier, it really is based on a currentdifferencing topology. The input stage uses precision 5-kΩ resistors internally to convert the voltage on the input
pin onto a current, so any resistance added in series with the input pins will change this resistance, and thus the
resulting current, causing an error. TI recommends that the total path resistance be less than 10 Ω and equal to
both inputs.
If a resistance is added in series with an input, the gain of that input will not track that of the other input, causing
a constant gain error.
TI does not recommend using external resistance to alter the gain, as external resistors do not have the same
thermal matching and tracking as the internal thin film resistors. Any added resistance will severely degrade the
offset and CMRR specifications.
If resistors are purposely added for filtering, resistance should be added equally to both inputs and be less than
10 Ω, and the user should be aware that the gain will change slightly.
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The LMP8645 device measures the small voltage developed across a current-sensing resistor when current
passes through it in the presence of high common-mode voltage. The gain is set by a single resistor and
buffered to a single-ended output.
8.2 Typical Applications
8.2.1 Typical Current Monitor Application
RS
IS
+
+IN
-IN
RIN
+
LMP8645
RIN
ACTIVE
DEVICE
+
V
+
VA
ADC
VOUT
+
-
V
RG
Figure 21. LMP8645 in Current Monitor Application
8.2.1.1 Design Requirements
In this example, the LMP8645 is used to monitor the supply current of an active device (Refer to Figure 21). The
LMP8645 supply voltage is 5 V and the active device is supplied with 12 V. The maximum load current is 1 A.
The LMP8645 will operate in all 3 ranges: in Range 1 when turning on the power of the active device (rising from
0 V to 12 V), while briefly passing through Range 2 as the load supply rises, and finally into Range 3 for normal
load operation.
Because the purpose of the application is monitor the current of the active device in any operating condition
(power on, normal operation, fault, and so forth), the gain resistor will be selected according to Range 1, the
range that puts the most constraints to the maximum output voltage swing of the LMP8645.
8.2.1.2 Detailed Design Procedure
At the start-up of the monitored device, the LMP8645 works at a common-mode voltage of 0 V, which means that
the maximum output limit is 1.3 V (Range 1). To maximize the resolution, the RSENSE value is calculated as
maximum allowed VSENSE (Refer to Figure 17) divided by maximum current (1 A), so RSENSE=0.5 Ω.
Due to the output limitation at low common-mode voltage, the maximum allowed gain will be 2.6 V/V, which
corresponds to RGAIN = 13 kΩ. With this approach the current is monitored correctly at any working condition, but
does not use the full output swing range of the LMP8645.
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Typical Applications (continued)
Alternatively if the monitored device doesn’t sink the full 1 A at any supply voltage, it is possible to design with
the full maximum output voltage of the LMP8645 when operating in Range 3 ( VCM ≥ VS ).
Also in this case it is possible to maximize the resolution using Rsense = 0.5 Ω, and maximize the output
dynamic range with RGAIN=33 kΩ. With this approach the maximum detectable current, when VCM is less than 1.8
V, is about 400 mA. While for common-mode voltages of less than 2.5 V the maximum detectable current is 600
mA (Refer to Figure 17), and for common-mode voltages at or above the LMP8645 supply voltage, the maximum
current is 1 A.
The second approach maximizes the output dynamic but implies some knowledge on the monitored current.
8.2.1.3 Application Curves
Figure 22 shows the resulting circuit voltages with the input load swept from 0 A to 1 A, with RGAIN= 13 kΩ for
operation in Range 1 (preferring accuracy over all load operating conditions).
Also shown in Figure 23 is the resulting output voltage with RGAIN = 33 kΩ for operation in Range 3 (sacrificing
low load supply accuracy while optimizing overall resolution at normal load operating conditions).
3.5
RG = 33k
Range 3
3.0
Vsense (V)
2.5
Output Voltage (V)
Output Voltage (V)
3.0
3.5
Output Voltage (V)
RG = 13k
Range 1
2.0
1.5
1.0
0.5
2.5
2.0
1.5
Output Voltage (V)
1.0
Vsense (V)
0.5
0.0
0.0
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
Load Current (A)
0.8
0.9
1.0
0.0
0.1
0.2
0.3
0.4
0.5
0.6
Load Current (A)
C002
Figure 22. Resulting Input and Output Voltages vs Load
Current for Range 1
0.7
0.8
0.9
1.0
C001
Figure 23. Resulting Input and Output Voltages vs Load
Current For Range 3
8.2.2 High Brightness LED Driver
The LMP8645 is the right choice in applications which require high-side current sense, such as High Brightness
LED for automotive where the cathode of the LED must be connected to the ground (chassis) of the car. In
Figure 24, the LMP8645 is used to monitor the current High Side in a high brightness LED together with a
LM3406 constant current buck regulator LED driver.
L
VIN
RS
IF
SW
+IN
LM3406HV
Constant Current
Buck Regulator
-IN
HB/HP
(3W-25W)
RIN LMP8645HV
RIN
VCC
+
CS
-
+
V
IF = 200 mV/(RS*Gain)
Gain = RGAIN*Gm
-
VOUT
+
-
RG
V
RGAIN
Figure 24. High-Side Current Sensing in Driving HP/HB LED
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Typical Applications (continued)
Even though LMP8645 will work in all 3 Ranges, RGAIN will be calculated according to Range 3 because the
purpose is regulating the current in the LEDs when the external MOSFET is OFF (LMP8645 at high VCM). Even if
this approach makes the LMP8645 able to sense high peak current only in Range 3 where the dynamic output is
higher than Range 1 the current resolution is maximized. At each switch ON/OFF of the MOSFET the LMP8645
goes from Range 1 (MOSFET ON, string of LED OFF), to Range 3 (MOSFET OFF, string of LED ON) passing
through Range 2 (MOSFET OFF, string of LED OFF). Because the purpose of the application is to sense the
current with high precision when the LED string is ON, the RGAIN will be calculated according to the Range 3.
The LMP8645 supply voltage is supplied by the internal LDO of the LM3406 thorough the pin VCC. The LM340x
is expecting a 200-mV feedback signal at the current sense (SNS) pin. The LMP8645 must provide this 200 mV
at the determined current limit.
The current which flows through the LED is programmed according to Equation 8:
IF = VCS / (RS × Gain)
where:
•
•
Gain = RGAIN × Gm
VCS = 200 mV
(8)
In this application the current which flows in the HB LED is in the Range from 350 mA to 1 A, so to reduce the
power dissipation on the shunt resistor and have a good accuracy, the RS must be in the range from 50 mΩ and
200 mΩ. In Table 1, two examples are analyzed.
To summarize, calculate the RGAIN according to the range of operation in which the application mainly works.
Once selected, the range considers the more stringent constraint
Table 1. Comparison of Two Ranges
IF=350 mA
IF=1 A
RGAIN
40 kΩ
36 kΩ
RS
77 mΩ
27 mΩ
Dissipated Power
9.5 mW
27 mW
Total Accuracy
≊5%
≊5%
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9 Power Supply Recommendations
To decouple the LMP8645 from AC noise on the power supply, TI recommends using a 0.1-μF bypass capacitor
between the VS and GND pins. This capacitor must be placed as close as possible to the supply pins. In some
cases, an additional 10-μF bypass capacitor may further reduce the supply noise.
10 Layout
10.1 Layout Guidelines
The traces leading to and from the sense resistor can be significant error sources. With small value sense
resistors (< 100 mΩ), any trace resistance shared with the load current can cause significant errors.
The amplifier inputs should be directly connected to the sense resistor pads using Kelvin or 4-wire connection
techniques. The traces should be one continuous piece of copper from the sense resistor pad to the amplifier
input pin pad, and ideally on the same copper layer with minimal vias or connectors. This can be important
around the sense resistor if it is generating any significant heat gradients.
To minimize noise pick-up and thermal errors, the input traces should be treated like a differential signal pair and
routed tightly together with a direct path to the input pins (preferably on the same copper layer). The input traces
should be run away from noise sources, such as digital lines, switching supplies or motor drive lines.
Ensure that the sense traces have the appropriate trace routing clearances for the expected load supply
voltages.
Because the sense traces only carry the amplifier bias current, the connecting input traces can be thinner, signal
level traces. Excessive Resistance in the trace should also be avoided.
The paths of the traces should be identical, including connectors and vias, so that any errors will be equal and
cancel.
The sense resistor will heat up as the load increases. As the resistor heats up, the resistance generally goes up,
which will cause a change in the readings. The sense resistor should have as much heatsinking as possible to
remove this heat through the use of heatsinks or large copper areas coupled to the resistor pads.
The gain set resistor pin is a sensitive node and can pick up noise. Keep the gain set resistor close to the RG pin
and minimize RGAIN trace length. Connect the grounded end of RGAIN directly to the LMP8645 ground pin.
10.2 Layout Example
Figure 25. Layout Example
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11 Device and Documentation Support
11.1 Device Support
11.1.1 Development Support
LMP8645 TINA SPICE Model, SNOM087
TINA-TI SPICE-Based Analog Simulation Program, http://www.ti.com/tool/tina-ti
Evaluation Board for the LMP8645, http://www.ti.com/tool/lmp8645mkeval
11.2 Documentation Support
11.2.1 Related Documentation
For related documentation, see the following:
AN-1975 LMP8640 / LMP8645 Evaluation Board User Guide, SNOA546
11.3 Related Links
The following table lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to sample or buy.
Table 2. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
LMP8645
Click here
Click here
Click here
Click here
Click here
LMP8645HV
Click here
Click here
Click here
Click here
Click here
11.4 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
For support, visit the Current Sense Amplifier E2E support forum at https://e2e.ti.com/support/amplifiers/currentshunt-monitors/
11.5 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
11.6 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
11.7 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
22
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Copyright © 2009–2015, Texas Instruments Incorporated
Product Folder Links: LMP8645 LMP8645HV
LMP8645, LMP8645HV
www.ti.com
SNOSB29G – NOVEMBER 2009 – REVISED SEPTEMBER 2015
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
Copyright © 2009–2015, Texas Instruments Incorporated
Product Folder Links: LMP8645 LMP8645HV
Submit Documentation Feedback
23
PACKAGE OPTION ADDENDUM
www.ti.com
17-Jun-2015
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
LMP8645HVMK/NOPB
ACTIVE
SOT
DDC
6
1000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 125
AK6A
LMP8645HVMKE/NOPB
ACTIVE
SOT
DDC
6
250
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 125
AK6A
LMP8645HVMKX/NOPB
ACTIVE
SOT
DDC
6
3000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 125
AK6A
LMP8645MK/NOPB
ACTIVE
SOT
DDC
6
1000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 125
AJ6A
LMP8645MKE/NOPB
ACTIVE
SOT
DDC
6
250
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 125
AJ6A
LMP8645MKX/NOPB
ACTIVE
SOT
DDC
6
3000
Green (RoHS
& no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
-40 to 125
AJ6A
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
17-Jun-2015
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
17-Jun-2015
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
LMP8645HVMK/NOPB
SOT
DDC
6
LMP8645HVMKE/NOPB
SOT
DDC
LMP8645HVMKX/NOPB
SOT
DDC
LMP8645MK/NOPB
SOT
LMP8645MKE/NOPB
LMP8645MKX/NOPB
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
1000
178.0
8.4
3.2
3.2
1.4
4.0
8.0
Q3
6
250
178.0
8.4
3.2
3.2
1.4
4.0
8.0
Q3
6
3000
178.0
8.4
3.2
3.2
1.4
4.0
8.0
Q3
DDC
6
1000
178.0
8.4
3.2
3.2
1.4
4.0
8.0
Q3
SOT
DDC
6
250
178.0
8.4
3.2
3.2
1.4
4.0
8.0
Q3
SOT
DDC
6
3000
178.0
8.4
3.2
3.2
1.4
4.0
8.0
Q3
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
17-Jun-2015
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LMP8645HVMK/NOPB
SOT
DDC
6
1000
210.0
185.0
35.0
LMP8645HVMKE/NOPB
SOT
DDC
6
250
210.0
185.0
35.0
LMP8645HVMKX/NOPB
SOT
DDC
6
3000
210.0
185.0
35.0
LMP8645MK/NOPB
SOT
DDC
6
1000
210.0
185.0
35.0
LMP8645MKE/NOPB
SOT
DDC
6
250
210.0
185.0
35.0
LMP8645MKX/NOPB
SOT
DDC
6
3000
210.0
185.0
35.0
Pack Materials-Page 2
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