LMP91000SDE/NOPB National Semiconductor, LMP91000SDE/NOPB Datasheet
LMP91000SDE/NOPB
Specifications of LMP91000SDE/NOPB
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LMP91000SDE/NOPB Summary of contents
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... Further power sav- ings are possible by switching off the TIA amplifier and shorting the reference electrode to the working electrode with an internal switch. Typical Application © 2011 National Semiconductor Corporation LMP91000 Features Typical Values, T ■ Supply voltage ■ ...
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Ordering Information Package Part Number LMP91000SD 14-Pin LLP LMP91000SDE LMP91000SDX Connection Diagram Pin Descriptions Pin Name 1 DGND 2 MENB AGND 8 VOUT VREF www.national.com Package Transport Media Marking ...
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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 Tolerance (Note 2) Human Body Model Charge-Device Model Machine Model Voltage between any two pins Current through VDD or VSS Current sunk and sourced by CE pin ...
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Symbol Parameter WE Voltage Offset referred to V OS_RW RE WE Voltage Offset Drift referred TcV to RE from -40°C to 85°C OS_RW (Note 8) TIA_GAIN Transimpedance gain accuracy Linearity Programmable TIA Gains www.national.com Conditions 0% VREF Internal Zero=20% VREF ...
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Symbol Parameter TIA_ZV Internal zero voltage Internal zero voltage Accuracy RL Programmable Load Load accuracy Power Supply Rejection Ratio at PSRR RE pin Temperature Sensor Specification (Refer to Temperature Error Sensitivity Power on time External reference specification VREF External Voltage ...
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Symbol Parameter Bus free time between a STOP and START t BUF condition t Data valid time VD;DAT t Data valid acknowledge time VD;ACK t Pulse width of spikes that must be SP suppressed by the input filter(Note t_timeout SCL ...
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Typical Performance Characteristics 2.7V <V < 5.25V and AGND = DGND =0V, VREF= 2.5V. S Input V vs. temperature (Vbias 0mV) OS_RW -100 VDD = 2.7V VDD = 3.3V -120 VDD = 5V -140 -160 -180 -200 -220 -240 -260 ...
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Supply current vs. temperature (Deep Sleep Mode) 1.0 VDD = 2.7V VDD = 3.3V 0.9 VDD = 5V 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 -50 - TEMPERATURE (°C) Supply current vs. temperature (Standby Mode) 7.50 VDD ...
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Supply current vs. temperature (Temp Measurement TIA ON) 17.0 VDD = 2.7V VDD = 3.3V 16.5 VDD = 5V 16.0 15.5 15.0 14.5 14.0 13.5 13.0 -50 - TEMPERATURE (°C) Supply current vs. temperature (Temp Measurement TIA OFF) ...
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TIME (s) 0.1Hz to 10Hz noise, 600mV bias 2.5 2.0 1.5 1.0 0.5 0.0 -0.5 -1.0 -1.5 -2.0 -2 ...
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Function Description GENERAL The LMP91000 is a programmable AFE for use in micropower chemical sensing applications. The LMP91000 is designed for 3-lead single gas sensors and for 2-lead galvanic cell sen- sors. This device provides all of the functionality for ...
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The Internal zero is provided through an internal voltage di- vider (Vref divider box in Figure 2). The divider is programmed through the interface. Temperature sensor The embedded temperature sensor can be switched off dur- ing gas ...
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WRITE AND READ OPERATION In order to start any read or write operation with the LMP91000, MENB needs to be set low during the whole com- munication. Then the master generates a start condition by driving SDA from high to ...
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TIMEOUT FEATURE The timeout is a safety feature to avoid bus lockup situation. If SCL is stuck low for a time exceeding t_timeout, the LMP91000 will automatically reset its I the case the LMP91000 hangs the SDA for a time ...
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TIACN -- TIA Control Register (address 0x10) The parameters in the TIA control register allow the configuration of the transimpedance gain ( Load Bit Name [7:5] RESERVED [4:2] TIA_GAIN [1:0] RLOAD REFCN -- Reference Control Register (address 0x11) ...
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MODECN -- Mode Control Register (address 0x12) The Parameters in the Mode register allow the configuration of the Operation Mode of the LMP91000. Bit Name 7 FET_SHORT [6:3] RESERVED [2:0] OP_MODE When the LMP91000 is in Temperature measurement (TIA ON) ...
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Galvanic Cell In Ground Referred Configuration When the LMP91000 is interfaced to a galvanic cell (for in- stance to an Oxygen gas sensor) referred to the ground of the system, an external resistor needs to be placed in parallel ...
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Galvanic Cell In Potentiostat Configuration When the LMP91000 is interfaced to a galvanic cell (for in- stance to an Oxygen gas sensor) referred to a reference, the Counter and the Reference pin of the LMP91000 are shorted together and ...
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FIGURE 6. 2-Lead Galvanic Cell In Potentiostat Configuration Application Information CONNECTION OF MORE THAN ONE LMP91000 TO THE BUS The LMP91000 comes out with a unique and fixed I address still possible to connect more ...
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SMART GAS SENSOR ANALOG FRONT END The LMP91000 together with an external EEPROM repre- sents the core of a SMART GAS SENSOR AFE. In the EEPROM it is possible to store the information related to the GAS sensor type, calibration ...
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On only happens a few times over life, so its power consumption can be ignored -Deep Sleep mode is not used -The system is used about 8 hours a day, and 16 hours a day Standby ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted NS Package Number SDA14B 22 ...
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Notes 23 www.national.com ...
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