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National LMP8272 LMP8277 handbook

1. 8277 is minimized by trimming amplifier A1 This is done so that the output re ferred offset of A1 cancels the input referred offset of A2 or 7Vos1 Vose Because of this offset voltage relationship the offset of each individual amplifier stage maybe more than the limit speci fied for the overall system in the datasheet tables Care must be given when pin 3 and 4 A1 and A2 are connected to each other If the signal going from A1 to A2 is amplified or attenuated by use of amplifiers and resistors the overall LMP8272 LMP8277 offset will be affected as a result Fil tering the signal between A1 and A2 or simply connecting the two pins will not change the offset of the LMP8272 LMP8277 Referencing input referred offset voltages the following re lationship holds 7Vos1 E Vos2 7 Vos LMP8272 LMP8277 If the signal on pin 3 is scaled attenuated or amplified by a factor X then the offset of the overall system will become 7Vos1 X Voss S V LMP8272 LMP8277 www national com ADI Auy BdUBIaJJIG LA UOIsida1d y JO UIN Spo UOWWOD yY IH Z Z8dIN1 7ZZ8d NT LMP8272 LMP8277 High Common Mode Gain of 14 Precision Voltage Difference Amplifier Application Note Continued This represents a value that the LMP8272 and LMP8277 have not been optimized and trimmed for and may very well www national com be above the limits indicated in the electrical characteristics tables National does not assu
2. Control m Low Side Driver Configuration Current Sensing m Power Management Systems Typical Application Typical Application Low side Current Sensing Vs 4 5V to 5 5V LMP8272 LMP8277 Inductive Load Aa n Proprietary i Level Shift tO Out Up To Circuitry i 27 Volts Eg Power Switch 20130901 s1 dwy eualeyiq eeyo UO S d Y Jo ULY Spo UOWWOD UBIH ZZZ8dIN1 ZZZ8d NT LMP is a trademark of National Semiconductor Corporation 2005 National Semiconductor Corporation DS201309 www national com LMP8272 LMP8277 High Common Mode Gain of 14 Precision Voltage Difference Amplifier Absolute Maximum Ratings Note 1 Junction Temperature Note 3 150 C max If Military Aerospace specified devices are required Soldering Information please contact the National Semiconductor Sales Office Infrared or Convection 20 sec 235 C Distributors for availability and specifications Wave Soldering Lead Temp 10 ESD Tolerance Note 2 sec 260 C Human Body Model For input pins only 4000V Operating Ratings Note 1 For All other pins 2000V Wachina Wodel 200V Temperature nange Note 3 Supply Voltage Vs GND 5 75V Packaged devices Note 3 40 C to 125 C Bare Die Junction Temperature Note 3 40 C to 150 C Supply Voltage Vs GND 4 5V to 5 5V CMVR Continuous 5 to 42 Volts l l Package Thermal Resistance 0 Note 3 Transient 300 ms TBD to 45 Volts l 8 Pin SOIC 190 C W St
3. O O LMP82721 O L National PRELIMINARY Semiconductor January 2005 LMP8272 LMP8277 High Common Mode Gain of 14 Precision Voltage Difference Amplifiers General Description Features The LMP 8272 LMP8277 are fixed gain differential ampli Typical Values TA 25 C fiers with a 2V to 27V input common mode voltage range Input Offset Voltage 1mV max and a supply voltage range of 4 5V to 5 5V The LMP8272 TCVos LMP8272 15uV C max LMP8277 are precision amplifiers which will detect amplify TCVos LMP8277 30uV C max and filter small differential signals in the presence of high CMRR 80dB Min common mode voltages The gain is fixed at 14 and is adequate to drive an ADC to full scale in most cases This LENEA ie a 19 mae fixed gain is achieved in two separate stages a pre amplifier Output Voltage Swing Rail to Rall Bandwidth 80KHz with gain of 7 and a second stage amplifier with a gain of 2 The internal signal path between these two stages is brought out on two pins that provide a connection for a filter network The LMP8272 LMP8277 will function with reduced specifi cations over the extended common mode input voltage range of 5 to 36 Volts This feature makes the device Applications suitable for applications with load dump in automotive sys tems Operating Temperature Range Ambient 40 C to 125 C Operating Temperature Range bare die 40 C to 150 C Supply Voltage 4 5V to 5 5V Supply Current 1mA m Fuel Injection
4. ded to be functional but specific performance is not guaranteed For guaranteed specifications and the test conditions see the Electrical Characteristics Tables Note 2 Human body model 1 5 KQ in series with 100 pF Machine model 0Q in series with 200 pF Note 3 The maximum power dissipation is a function of T ymax 99a and Ta The maximum allowable power dissipation at any ambient temperature is Pp Tymax y Ta 8g All numbers apply for packages soldered directly onto a PC board Note 4 Typical values represent the most likely parametric norm Note 5 Positive current corresponds to current flowing into the device Note 6 Slew rate is the average of the rising and falling slew rates Note 7 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 Connection Diagram 8 Pin SOIC LMP8272 LMP8277 20130902 Top View Application Note The LMP8272 LMP8277 are single supply amplifier with a fixed gain of 14 and an extended common mode voltage range of 2V to 36V The fixed gain is achieved in two separate stages a pre amplifier with gain of 7 and a sec ond stage amplifier with gain of 2 A block diagram of the LMP8272 LMP8277 is shown in Figure 1 Vg 4 5V to 5 5V LMP8272 LMP8277 Proprietary Level Shift Circuitry 20130903 FIGURE 1 The overall offset of the LMP8272 LMP
5. emiconductor Americas Customer Europe Customer Support Center Support Center Fax 49 0 180 530 85 86 Email new feedback nsc com Email europe support nsc com Tel 1 800 272 9959 Deutsch Tel 49 0 69 9508 6208 English Tel 44 0 870 24 0 2171 www national com Fran ais Tel 33 0 1 41 91 8790 National Semiconductor National Semiconductor Asia Pacific Customer Japan Customer Support Center Support Center Fax 81 3 5639 7507 Email ap support nsc com Email jon feedback nsc com Tel 81 3 5639 7560 s1 dwy eUaJeyiG eeyo UO S d Yi Jo ULY Spo UOWWOD UBIH ZZZ8dINT ZZZ8d NT
6. me any responsibility for use of any circuitry described no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications For the most current product information visit us at www national com LIFE SUPPORT POLICY NATIONAL S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION As used herein 1 Life support devices or systems are devices or systems which a are intended for surgical implant into the body or b support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in a significant injury to the user BANNED SUBSTANCE COMPLIANCE 2 Acritical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification CSP 9 111C2 and the Banned Substances and Materials of Interest Specification CSP 9 111S2 and contain no Banned Substances as defined in CSP 9 111S2 National Semiconductor National S
7. orage Temperature Range 65 C to 150 C 5V Electrical Characteristics note 7 Unless otherwise specified all limits guaranteed for Ta 25 C Vs 5V GND 0 2V lt Vecm lt 27V Boldface limits apply at the temperature extremes Symbol Parameter Conditions Typ Units Note 4 ls Supply Current 0 6 1 0 1 2 mA Seo o de Rom Input impedance Common 200 KQ ae n S S Rom Input impedance Differential 400 480 KQ resem a CMVR Input Common Mode Voltage Continuous 27 V range en fom ECMVR Extended Common Mode 5 36 V Vougerage FL a R DC DC Common Mode Rejection 2V lt Vcm lt 27V 80 dB AC AC Common Mode Rejection 2V lt Vcm lt 27V f 1KHz TD f dB PSRR ___ Power Supply Rejection Ratio 4 5V lt V e lt 5 5V m dB TBD a aaen S Genero A1 Vour A1 Output Voltage Swing R 100KQ on Output oo Volts va fao o A2 Vour A2 Output Voltage Swing R 100K2 on Output voL oo vois 80 s SewRateWoes OOOO o O o dC sw fewn O O O o CK auj Jw dl i www national com 2 5V Electrical Characteristics Note 7 Continued Unless otherwise specified all limits guaranteed for Ta 25 C Vs 5V GND 0 2V lt Vem lt 27V Boldface limits apply at the temperature extremes b Noise 0 1Hz ro 10Hz Spectral Density Conditions Note 1 Absolute Maximum Ratings indicate limits beyond which damage to the device may occur Operating Ratings indicate conditions for which the device is inten

National LMP8272 LMP8277 handbook

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