LMP7312MA NSC [National Semiconductor], LMP7312MA Datasheet
LMP7312MA
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LMP7312MA Summary of contents
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Precision SPI-Programmable AFE with Differential/Single- Ended Input/Output General Description The LMP7312 is a digitally programmable variable gain am- plifier/attenuator. Its wide input voltage range and superior precision make it a prime choice for applications requiring high accuracy such as data ...
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Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. ESD Rating (Note 2) Human Body Model Machine Body Model Charge device Model Analog Supply Voltage ( ...
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Symbol Parameter V V Output Offset V OCM_OS OCM OCM (Note 8) V Positive Output kΩ, C OUT L Voltage Swing +V IN Negative Output kΩ Voltage Swing + ...
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Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but for which specific performance is not guaranteed. For guaranteed specifications and ...
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Test Circuit Diagram Timing Diagram 30075510 5 30075509 www.national.com ...
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... Negative supply voltage, reference for both Analog and Digital supplies 14 SCK SPI Clock Ordering Information Package Part Number LMP7312MA 14-Pin SOIC LMP7312MAX www.national.com 14-Pin SOIC 30075502 Top View Package Marking Transport Media 95 Units/Rail LMP7312MA 2.5k units Tape and Reel 6 NSC Drawing M14A ...
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Typical Performance Characteristics Unless otherwise specified 25° =50pF, Differential output configuration. L Offset Voltage distribution (PMOS) TCV distribution (PMOS) OS Noise vs. Frequency (Core op-amp 5V 5V, V − = 0V, ...
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Gain vs. Frequency (Attenuation Mode) CMRR vs. Frequency (Attenuation Mode) PSRR (Core op-amp) www.national.com Gain vs. Frequency (Amplification Mode) 30075521 CMRR vs. Frequency (Amplification Mode) 30075536 Vos vs. Input Common Mode Voltage 30075523 8 30075522 30075537 30075545 ...
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Small signal step (Attenuation Mode) 30075524 Large signal step (Attenuation Mode) 30075526 Settling time – Rise (Attenuation Mode) 30075528 Small signal step (Amplification Mode) Large signal step (Amplification Mode) Settling time – Rise (Amplification Mode) 9 30075525 30075527 30075529 www.national.com ...
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Settling time – Fall (Attenuation Mode) Gain change (Attenuation Mode) THD + N (Attenuation Mode) www.national.com Settling time – Fall (Amplification Mode) 30075530 Gain change (Amplification Mode) 30075532 THD + N (Amplification Mode) 30075534 10 30075531 30075533 30075535 ...
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I vs Short Circuit Current +V vs. Temperature OUT Output voltage swing +V vs. Output current OUT I VIO 30075551 Short Circuit Current -V 30075541 Output voltage swing -V 30075543 11 vs. V Voltage IO 30075550 vs. ...
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SDO sink current vs. SDO Voltage www.national.com SDO source current vs. SDO Voltage 30075539 12 30075538 ...
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Application Section GENERAL DESCRIPTION The LMP7312 is a single supply programmable gain differ- ence amplifier with two input pairs: Attenuation pair (- and Amplification pair (-IN, +IN). The output can be IN configured in both single-ended and differential ...
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FIGURE 2. Bipolar Input Signal to Single-Ended ADC Interface FIGURE 3. Unipolar Input Signal to Single-Ended ADC Interface www.national.com 14 30075504 30075505 ...
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INPUT VOLTAGE RANGE The LMP7312 has an internal OpAmp with rail-to-rail input voltage range capability. The requirement to stay within the V - and V + rail at the OpAmp input translates in an Input Volt- age Range specification as ...
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Gain_0, Gain_1 bit: Gain Values Different gains are available in Attenuation Mode or Amplifi- cation Mode according to the following Gain Table. Gain_1 Gain_0 EN_CL ...
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In each case the SPI registers require 5 bits. The table below is a summary of all allowed configurations. MSB Gain_1 Gain_0 EN_CL Daisy ...
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LMP7312 IN 4-20mA CURRENT LOOP APPLICATION The 4-20mA current loop shown in method of transmitting sensor information in many industrial process-monitoring applications. Transmitting sensor infor- mation via a current loop is particularly useful when the infor- mation has to be ...
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Parameter Gain Total Offset Input Referred (MAX) Total Offset Output Referred (MAX) TCV Input Referred @ 25°C (MAX) OS TCV Output Referred @ 25°C (MAX) OS Noise calculation Listed in the table below are the calculated values for Voltage Noise ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 14-Pin SOIC NS Package Number M14A 20 ...
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Notes 21 www.national.com ...
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