Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Op-amp Current sensor VSSOP 8

Charger

load

+3.3V

24V

48V

Inductive

Load

Inductive

Load

+5V

LMP8602, LMP8602Q, LMP8603, LMP8603Q

www.ti.com

SNOSB36D –JULY 2009–REVISED MARCH 2013

60V Common Mode, Fixed Gain, Bidirectional Precision Current Sensing Amplifier

Check for Samples: LMP8602, LMP8602Q, LMP8603, LMP8603Q

FEATURES

DESCRIPTION

The LMP8602 and LMP8603 are fixed gain precision

• Unless Otherwise Noted, Typical Values at T

amplifiers. The parts will amplify and filter small

= 25°C, V

= 5.0V, Gain = 50x (LMP8602), Gain

differential signals in the presence of high common

= 100x (LMP8603)

mode voltages. The input common mode voltage

• TCV

10μV/°C max

range is –22V to +60V when operating from a single

5V supply. With a 3.3V supply, the input common

• CMRR 90 dB Min

mode voltage range is from –4V to +27V. The

• Input Offset Voltage 1 mV Max

LMP8602 and LMP8603 are members of the Linear

• CMVR at V

= 3.3V −4V to 27V

Monolithic Precision (LMP

) family and are ideal

• CMVR at V

= 5.0V −22V to 60V

parts for unidirectional and bidirectional current

sensing applications. All parameter values of the

• Operating Ambient Temperature Range −40°C

parts that are shown in the tables are 100% tested

to 125°C

and all bold values are also 100% tested over

• Single Supply Bidirectional Operation

temperature.

• All Min / Max Limits 100% Tested

The parts have a precise gain of 50x for the

• LMP8602Q and LMP8603Q Available in

LMP8602 and 100x for the LMP8603, which are

Automotive AEC-Q100 Grade 1 Qualified

adequate in most targeted applications to drive an

Version

ADC to its full scale value. The fixed gain is achieved

in two separate stages, a preamplifier with a gain of

10x and an output stage buffer amplifier with a gain

APPLICATIONS

of 5x for the LMP8602 and 10x for the LMP8603. The

• High Side and Low Side Driver Configuration

connection between the two stages of the signal path

Current Sensing

is brought out on two pins to enable the possibility to

• Bidirectional Current Measurement create an additional filter network around the output

buffer amplifier. These pins can also be used for

• Current Loop to Voltage Conversion

alternative configurations with different gain as

• Automotive Fuel Injection Control

described in the applications section.

• Transmission Control

• Power Steering

• Battery Management Systems

Typical Applications

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.

Summary of content (33 pages)

PAGE 1
LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 60V Common Mode, Fixed Gain, Bidirectional Precision Current Sensing Amplifier Check for Samples: LMP8602, LMP8602Q, LMP8603, LMP8603Q FEATURES DESCRIPTION • The LMP8602 and LMP8603 are fixed gain precision amplifiers. The parts will amplify and filter small differential signals in the presence of high common mode voltages.
PAGE 2
LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com DESCRIPTION (CONTINUED) The mid-rail offset adjustment pin enables the user to use these devices for bidirectional single supply voltage current sensing. The output signal is bidirectional and mid-rail referenced when this pin is connected to the positive supply rail. With the offset pin connected to ground, the output signal is unidirectional and groundreferenced.
PAGE 3
LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 Operating Ratings (1) Supply Voltage (VS – GND) 3.0V to 5.
PAGE 4
LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com 3.3V Electrical Characteristics(1) (continued) Unless otherwise specified, all limits ensured at TA = 25°C, VS = 3.3V, GND = 0V, −4V ≤ VCM ≤ 27V, and RL = ∞, Offset (Pin 7) is grounded, 10nF between VS and GND. Boldface limits apply at the temperature extremes.
PAGE 5
LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 5V Electrical Characteristics(1) (continued) Unless otherwise specified, all limits ensured for at TA = 25°C, VS = 5V, GND = 0V, −22V ≤ VCM ≤ 60V, and RL = ∞, Offset (Pin 7) is grounded, 10nF between VS and GND. Boldface limits apply at the temperature extremes. Symbol PSRR Parameter Power Supply Rejection Ratio Conditions DC 4.5V ≤ VS ≤ 5.
PAGE 6
LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com BLOCK DIAGRAM OFFSET VS 7 6 Level shift +IN 8 + Preamplifier Gain = 10 -IN Output Buffer Gain = K2 5 OUT - 1 100 k: 2 GND 3 4 A1 A2 Figure 1. K2 = 5 for LMP8602, K2 = 10 for LMP8603 Connection Diagram -IN 1 8 +IN GND 2 7 OFFSET A1 3 6 VS A2 4 5 OUT Figure 2.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 Typical Performance Characteristics Unless otherwise specified, all limits ensured for at TA = 25°C, VS = 5V, GND = 0V, −22V ≤ VCM ≤ 60V, and RL = ∞, Offset (Pin 7) connected to VS, 10nF between VS and GND. 125°C 85°C 1.0 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 VOS vs. VCM at VS = 5V VOFFSET (mV) VOFFSET (mV) VOS vs. VCM at VS = 3.3V 25°C -40°C 125°C 85°C 1.0 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com Typical Performance Characteristics (continued) Unless otherwise specified, all limits ensured for at TA = 25°C, VS = 5V, GND = 0V, −22V ≤ VCM ≤ 60V, and RL = ∞, Offset (Pin 7) connected to VS, 10nF between VS and GND. Input Referred Voltage Noise vs. Frequency PSRR vs. Frequency 1.5 100 80 VS = 5V PSRR (dB) VOLTAGE NOISE (PV/ Hz) VS = 5V 1.2 0.9 0.6 VS = 3.3V 0.3 VS = 3.3V 60 40 20 0 0.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 Typical Performance Characteristics (continued) Unless otherwise specified, all limits ensured for at TA = 25°C, VS = 5V, GND = 0V, −22V ≤ VCM ≤ 60V, and RL = ∞, Offset (Pin 7) connected to VS, 10nF between VS and GND. Step Response at VS = 5V RL = 10kΩ LMP8602 OUTPUT SIGNAL (1V/DIV) OUTPUT SIGNAL (1V/DIV) INPUT SIGNAL (50 mV/DIV) INPUT SIGNAL (50 mV/DIV) Step Response at VS = 3.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com Typical Performance Characteristics (continued) Unless otherwise specified, all limits ensured for at TA = 25°C, VS = 5V, GND = 0V, −22V ≤ VCM ≤ 60V, and RL = ∞, Offset (Pin 7) connected to VS, 10nF between VS and GND. Step Response at VS = 3.3V RL = 10kΩ LMP8603 Step Response at VS = 5V RL = 10kΩ LMP8603 VIN (20 mV/DIV) 8 7 6 5 6 5 4 3 3 2 1 0 2 1 0 Figure 21. Figure 22.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 Typical Performance Characteristics (continued) Unless otherwise specified, all limits ensured for at TA = 25°C, VS = 5V, GND = 0V, −22V ≤ VCM ≤ 60V, and RL = ∞, Offset (Pin 7) connected to VS, 10nF between VS and GND. Positive Swing vs. RLOAD at VS = 3.3V Positive Swing vs. RLOAD VS = 5V 3.30 5.00 4.98 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) 3.28 3.26 3.24 4.96 4.94 4.92 3.22 4.90 3.20 1k 10k 4.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com Typical Performance Characteristics (continued) Unless otherwise specified, all limits ensured for at TA = 25°C, VS = 5V, GND = 0V, −22V ≤ VCM ≤ 60V, and RL = ∞, Offset (Pin 7) connected to VS, 10nF between VS and GND. Gain error Distribution at VS = 3.3V LMP8602 5000 parts 20 Gain error Distribution at VS = 3.3V LMP8603 5000 parts 20 25°C VS = 3.
PAGE 13
LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 Typical Performance Characteristics (continued) Unless otherwise specified, all limits ensured for at TA = 25°C, VS = 5V, GND = 0V, −22V ≤ VCM ≤ 60V, and RL = ∞, Offset (Pin 7) connected to VS, 10nF between VS and GND. VOS Distribution at VS = 3.3V 5000 parts VOS Distribution at VS = 5V 5000 parts 35 30 30 PERCENTAGE (%) PERCENTAGE (%) 25°C 35 25 20 -40°C 125°C 15 10 5 25 20 -40°C 125°C 15 10 5 0 -1.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com APPLICATION INFORMATION GENERAL The LMP8602 and LMP8603 are fixed gain differential voltage precision amplifiers with a gain of 50x for the LMP8602, and 100x for the LMP8603. The input common mode voltage range is -22V to +60V when operating from a single 5V supply or -4V to +27V input common mode voltage range when operating from a single 3.3V supply.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 ADDITIONAL SECOND ORDER LOW PASS FILTER The LMP8602/LMP8602Q/LMP8603/LMP8603Q has a third order Butterworth low-pass characteristic with a typical bandwidth of 60 kHz integrated in the preamplifier stage of the part.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com For any filter gain K > 1x, the design procedure can be very simple if the two capacitors are chosen to in a certain ratio.
PAGE 17
LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 For C2 the value is calculated with: C2 = C1 K2 1 (14) Or for a gain = 5: C2 = C1 4 (15) and for a gain = 10: C2 = C1 9 (16) Note that the frequency response achieved using this procedure will only be accurate if the cut-off frequency of the second order filter is much smaller than the intrinsic 60 kHz low-pass filter.
PAGE 18
LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com For the LMP8603: Gr = 100 Rr Rr + 100 k: (18) Given a desired value of the reduced gain Gr, using this equation the required value for Rr can be calculated for the LMP8602 with: Rr = 100 k: X Gr 50 - Gr (19) and for the LMP8603 with: Rr = 100 k: x Gr 100 - Gr (20) Figure 45 shows the configuration that can be used to reduce the gain of the LMP8602 and the LMP8603 in bidirectional sensing applications.
PAGE 19
LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 and for the LMP8603 with: Ri = 900 k: x Gi Gi - 100 (24) It should be noted from the equation for the gain Gi that for large gains Ri approaches 100 kΩ x (K2 - 1). In this case, the denominator in the equation becomes close to zero. In practice, for large gains the denominator will be determined by tolerances in the values of the external resistor Ri and the internal 100 kΩ resistor, and the K2 gain error.
PAGE 20
LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com LAYOUT CONSIDERATIONS The two input signals of the LMP8602/LMP8602Q/LMP8603/LMP8603Q are differential signals and should be handled as a differential pair. For optimum performance these signals should be closely together and of equal length. Keep all impedances in both traces equal and do not allow any other signal or ground in between the traces of this signals.
PAGE 21
LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 VS = 5V 0.4 0.2 VOUT (V) 0 -0.2 -0.4 -0.6 10 pF -0.8 20 pF -1.0 0 50 100 150 200 250 300 TIME (ns) Figure 49. Capacitive Load Response at 5.0V These figures can be used to estimate the disturbance that will be caused when driving a switched capacitive load.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com OFFSET 7 INDUCTIVE LOAD +IN 8 RSENSE 1 5 Output Buffer Gain = K2 Preamplifier Gain = 10 - -IN + 24V + Level shift OUT - Internal Resistor 100 k: 3 4 A2 A1 POWER SWITCH C1 Figure 51.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 BATTERY CURRENT MONITOR APPLICATION This application example shows how the LMP8602/LMP8603 can be used to monitor the current flowing in and out a battery pack. The fact that the LMP8602/LMP8603 can measure small voltages at a high offset voltage outside the parts own supply range makes this part a very good choice for such applications.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q SNOSB36D – JULY 2009 – REVISED MARCH 2013 www.ti.com ILoad LOAD VS ICharge - ILoad OFFSET 7 +IN 8 ICharge RSENSE 1 -IN Output Buffer Gain = K2 Preamplifier Gain = 10 - 5 OUT A/D Internal Resistor 100 k: + 12V + Level shift - 3 4 A2 A1 C1 Charge Controler Charger K2 = 5 for LMP8602 K2 = 10 for LMP8603 Figure 54.
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LMP8602, LMP8602Q, LMP8603, LMP8603Q www.ti.com SNOSB36D – JULY 2009 – REVISED MARCH 2013 REVISION HISTORY Changes from Revision C (March 2013) to Revision D • Page Changed layout of National Data Sheet to TI format ..........................................................................................................
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE OPTION ADDENDUM www.ti.
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PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant LMP8602MAX/NOPB SOIC D 8 2500 330.0 12.4 6.5 5.4 2.0 8.0 12.0 Q1 LMP8602MM/NOPB VSSOP DGK 8 1000 178.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1 LMP8602MME/NOPB VSSOP DGK 8 250 178.0 12.4 5.3 3.4 1.4 8.0 12.
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PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LMP8602MAX/NOPB SOIC D 8 2500 367.0 367.0 35.0 LMP8602MM/NOPB VSSOP DGK 8 1000 210.0 185.0 35.0 LMP8602MME/NOPB VSSOP DGK 8 250 210.0 185.0 35.0 LMP8602MMX/NOPB VSSOP DGK 8 3500 367.0 367.0 35.0 LMP8602QMAX/NOPB SOIC D 8 2500 367.0 367.0 35.0 LMP8602QMM/NOPB VSSOP DGK 8 1000 210.0 185.0 35.
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