SNVSAL6A July   2016  – February 2017 LMP8480-Q1 , LMP8481-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
      1. 8.1.1 Theory of Operation
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1  Basic Connections
      2. 8.3.2  Selection of the Sense Resistor
      3. 8.3.3  Using PCB Traces as Sense Resistors
      4. 8.3.4  VREFA and VREFB Pins (LMP8481-Q1 Only)
        1. 8.3.4.1 One-to-One (1:1) Reference Input
        2. 8.3.4.2 Setting Output to One-Half VCC or external VREF
      5. 8.3.5  Reference Input Voltage Limits (LMP8481-Q1 Only)
      6. 8.3.6  Low-Side Current Sensing
      7. 8.3.7  Input Series Resistance
      8. 8.3.8  Minimum Output Voltage
      9. 8.3.9  Swinging Output Below Ground
      10. 8.3.10 Maximum Output Voltage
    4. 8.4 Device Functional Modes
      1. 8.4.1 Unidirectional vs Bidirectional Operation
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Input Common-Mode and Differential Voltage Range
    2. 9.2 Typical Applications
      1. 9.2.1 Unidirectional Application With the LMP8480-Q1
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Bidirectional Current Sensing Using the LMP8481-Q1
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curve
      3. 9.2.3 Typical Application With a Resistive Divider
  10. 10Power Supply Recommendations
    1. 10.1 Power Supply Decoupling
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
    2. 12.2 Related Links
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Community Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7 Specifications

7.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(4)(2)(1)
MIN MAX UNIT
Supply voltage (VCC to GND) –0.3 85 V
RSP or RSN to GND –0.3 85 V
VOUT to GND –0.3 to the lesser of (VCC + 0.3) or +20 V
VREF pins
(LMP8481-Q1 only)		 Other VREF pin tied to ground –0.3 12 V
Applied to both VREF pins tied together –0.3 6
Differential input voltage –85 85 V
Current into output pin –20(5) 20 mA
Current into any other pins –5(5) 5 mA
Operating temperature –40 125 °C
Junction temperature –40 150 °C
Storage temperature –65 150 °C
(1) 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.
(2) If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office/Distributors for availability and specifications.
(3) Exceeding the Recommended Operating Conditions for extended periods of time may effect device reliability or cause parametric shifts.
(4) The maximum power dissipation must be derated at elevated temperatures and is dictated by TJ(MAX), θJA, and the ambient temperature, TA. The maximum allowable power dissipation PDMAX = (TJ(MAX) –TA) / θJA or the number given in Absolute Maximum Ratings, whichever is lower.
(5) When the input voltage (VIN) at any pin exceeds power supplies (VIN < GND or VIN > VS ), the current at that pin must not exceed 5 mA, and the voltage (VIN) has to be within the Absolute Maximum Ratings for that pin. The 20-mA package input current rating limits the number of pins that can safely exceed the power supplies with current flow to four pins.

7.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2000 V
Charged-device model (CDM), per JEDEC specification JESD22-C101(2) ±750
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

7.3 Recommended Operating Conditions

expected normal operating conditions over free-air temperature range (unless otherwise noted)(3)
MIN MAX UNIT
Supply voltage (VCC) 4.5 76 V
Common mode voltage 4.0 76 V
Reference input (LMP8481-Q1 only) VREFA and VREFB tied together –0.3 to the lesser of (VCC – 1.5) or +6 V
Single VREF pin with other VREF pin grounded –0.3 or +12 where the average of the two VREF pins is less than the lesser of (VCC – 1.5) or +6 V

7.4 Thermal Information

THERMAL METRIC(1) LMP8480-Q1, LMP8481-Q1 UNIT
DGK (VSSOP)
8 PINS
RθJA Junction-to-ambient thermal resistance 185 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.

7.5 Electrical Characteristics

unless otherwise specified, all limits specified for at TA = 25°C, VCC = 4.5 V to 76 V, 4.5 V ≤ VCM ≤ 76 V, RL = 100 kΩ,
VSENSE = (VRSP – VRSN) = 0 V(1)
PARAMETER TEST CONDITIONS MIN(3) TYP(2) MAX(3) UNIT
VOS Input offset voltage (RTI) VCC = VRSP = 48 V,
ΔV = 100 mV 		TA = 25°C ±80 ±265 µV
–40°C ≤ TA ≤ 125°C ±900
TCVOS Input offset voltage drift(4) ±6 µV°C
IB Input bias current(7) VCC = VRSP = 76 V, per input 6.3 μA
VCC = VRSP = 76 V, per input,
–40°C ≤ TA ≤ 125°C		 12
ILEAK Input leakage current VCC = 0, VRSP = 86 V, both inputs together 0.01 μA
VCC = 0, VRSP = 86 V, both inputs together,
–40°C ≤ TA ≤ 125°C		 2
VSENSE (MAX) Differential input voltage across sense resistor(6) VCC = 16 -T version,
–40°C ≤ TA ≤ 125°C		 667 mV
-S version,
–40°C ≤ TA ≤ 125°C		 222
-H version,
–40°C ≤ TA ≤ 125°C		 133
AV Gain -T version 20 V/V
-T version, –40°C ≤ TA ≤ 125°C 19.8 20.2
-S version 60
-S version, –40°C ≤ TA ≤ 125°C 59.5 60.5
-H version 100
-H version, –40°C ≤ TA ≤ 125°C 99.2 100.8
Gain error VCC = VRSP = 48 V TA = 25°C ±0.6%
–40°C ≤ TA ≤ 125°C ±0.8%
DC PSRR DC power-supply rejection ratio VRSP = 48 V, VCC = 4.5 to 76 V 122 dB
VRSP = 48 V, VCC = 4.5 to 76 V,
–40°C ≤ TA ≤ 125°C		 100
DC CMRR DC common-mode rejection ratio VCC = 48 V, VRSP = 4.5 to 76 V 124 dB
VCC = 48 V, VRSP = 4.5 to 76 V,
–40°C ≤ TA ≤ 125°C		 100
VCC = 48 V, VRSP = 4 to 76 V 124
CMVR Input common-mode voltage range CMRR > 100 dB, –40°C ≤ TA ≤ 125°C 4 76 V
ROUT Output resistance, load regulation VSENSE = 100 mV 0.1 Ω
VOMAX Maximum output voltage (headroom)
(VOMAX = VCC – VOUT) 		VCC = 4.5 V, VRSP = 48 V, VSENSE = +1 V,
IOUT (sourcing) 500 μA 		230 500 mV
VOMIN Minimum output voltage VCC = VRSP = 48 V, VSENSE = –1 V,
IOUT (sinking) = 10 µA		 3 mV
VCC = VRSP = 48 V, VSENSE = –1 V,
IOUT (sinking) = 10 µA, –40°C ≤ TA ≤ 125°C		 15
VCC = VRSP = 4.5 V, VSENSE = –1 V,
IOUT (sinking) = 10 µA		 3
VCC = VRSP = 48 V, VSENSE = –1 V,
IOUT (sinking) = 100 µA		 18
VCC = VRSP = 48 V, VSENSE = –1 V,
IOUT (sinking) = 100 µA, –40°C ≤ TA ≤ 125°C		 55
VCC = VRSP = 4.5 V, VSENSE = –1 V,
IOUT (sinking) = 100 µA		 18
VOLOAD Output voltage with load VCC = 28 V, VRSP = 28 V, VSENSE = 600 mV,
I OUT (sourcing) = 500 µA 		12 V
VOLREG Output load regulation VCC = 20, VRSP = 16 V, VOUT = 12,
ΔIL = 200 nA to 8 mA 		0.001%
ICC Supply current VOUT = 2 V, RL = 10 MΩ, VCC = VRSP = 76 V 88 100 µA
VOUT = 2 V, RL = 10 MΩ, VCC = VRSP = 76 V, –40°C ≤ TA ≤ 125°C 155
BW –3-dB bandwidth RL = 10 MΩ, CL = 20 pF 270 kHz
SR Slew rate(5) VSENSE from 10 mV to 80 mV, RL = 10 MΩ,
CL = 20 pF		 1 V/µs
eni Input-referred voltage noise f = 1 kHz 95 nV/√Hz
tSETTLE Output settling time to 1% of final value VSENSE = 10 mV to 100 mV and 100 mV
to 10 mV		 20 µs
tPU Power-up time VCC = VRSP = 48 V, VSENSE = 100 mV, output to 1% of final value 50 µs
tRECOVERY Saturation recovery time Output settles to 1% of final value, the device does not experience phase reversal when overdriven 50 µs
CLOAD Max output capacitance load No sustained oscillations 500 pF
(1) Electrical Characteristics 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.
(2) Typical values represent the most likely parametric norm at the time of characterization. Actual typical values can vary over time and also depend on the application and configuration. The typical values are not tested and are not ensured on shipped production material.
(3) All limits are specified by testing, design, or statistical analysis.
(4) Offset voltage temperature drift is determined by dividing the change in VOS at the temperature extremes by the total temperature change.
(5) The number specified is the average of rising and falling slew rates and measured at 90% to 10%.
(6) This parameter is specified by design and/or characterization and is not tested in production.
(7) Positive bias current corresponds to current flowing into the device.

7.6 Typical Characteristics

unless otherwise specified, TA = 25°C, VCC = 4.5 V to 76 V, 4.5 V < VCM < 76 V, RL = 100 kΩ, VSENSE = (VRSP – VRSN) = 0 V, for all gain options
LMP8480-Q1 LMP8481-Q1 30191519.png Figure 1. Offset Voltage Histogram
LMP8480-Q1 LMP8481-Q1 30191509.png Figure 3. Typical Gain Accuracy vs Temperature
LMP8480-Q1 LMP8481-Q1 30191514.png Figure 5. Typical Offset Voltage vs Supply Voltage
LMP8480-Q1 LMP8481-Q1 30191517.png Figure 7. AC Power Supply Rejection Ratio vs Frequency
LMP8480-Q1 LMP8481-Q1 30191559.png Figure 9. Large Signal Pulse Response
LMP8480-Q1 LMP8481-Q1 30191511.png Figure 11. Supply Current vs Supply Voltage
LMP8480-Q1 LMP8481-Q1 30191504.png Figure 13. Saturated Output Sourcing Current at 4.5 V
LMP8480-Q1 LMP8481-Q1 30191506.png Figure 15. Saturated Output Sourcing Current at 12 V
LMP8480-Q1 LMP8481-Q1 30191508.png Figure 2. Typical Offset Voltage vs Temperature
LMP8480-Q1 LMP8481-Q1 30191512.png Figure 4. Typical Gain Accuracy vs Supply Voltage
LMP8480-Q1 LMP8481-Q1 30191516.png Figure 6. AC Common-Mode Rejection Ratio vs Frequency
LMP8480-Q1 LMP8481-Q1 tc_sm_sig_gain_frequency_snvsal6.gif Figure 8. Small Signal Gain vs Frequency
LMP8480-Q1 LMP8481-Q1 30191560.png Figure 10. Small Signal Pulse Response
LMP8480-Q1 LMP8481-Q1 30191510.png Figure 12. Supply Current vs Temperature
LMP8480-Q1 LMP8481-Q1 30191505.png Figure 14. Saturated Output Sinking Current at 4.5 V
LMP8480-Q1 LMP8481-Q1 30191507.png Figure 16. Saturated Output Current Sinking at 12 V