lm9040 National Semiconductor Corporation, lm9040 Datasheet
lm9040
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lm9040 Summary of contents
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... LM9040 Dual Lambda Sensor Interface Amplifier General Description The LM9040 is a dual sensor interface circuit consisting of two independent sampled input differential amplifiers de- signed for use with conventional Lambda Oxygen Sensors. The Lambda Sensor is used for monitoring the oxygen con- centration in the exhaust of gasoline engines using catalytic after treatment and will deliver a voltage signal which is dependent on the air-fuel mixture ...
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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. Supply Voltage Input Voltage Continuous (Note 2) Input Voltage Transient (Note 2) ESD Susceptibility (Note 3) ...
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Typical Performance Characteristics Supply Current vs Temperature F (Normalized CLOCK Z vs Temperature DIFF F CLOCK 01237204 CC 01237206 01237208 3 (Normalized OSC 01237205 Output R vs Temperature 01237207 F vs Temperature C 01237209 www.national.com ...
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Typical Performance Characteristics Voltage Gain vs Frequency CMRR vs Frequency www.national.com (Continued) 01237210 01237212 4 PSRR vs Frequency 01237211 ...
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... Circuit Description The LM9040 is fabricated in CMOS technology and is de- signed to operate from a single, well regulated, 5V supply. The IC consists of two independent differential amplifiers which are designed using two-phased switched capacitor networks (SCN). The differential inputs have a common mode operating range of 2V above and below ground. The SCN includes the input sampling, the lowpass filter, cold sensor bias voltage, and the gain circuitry ...
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... FIGURE 6. Differential and Common Mode Filtering Common Mode Filtering The differential input sampling of the LM9040 actually re- duces the effects of common mode input noise at low fre- quencies. The time interval between the sampling of the inverting input and the non-inverting input is one half and the inverting clock period ...
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... For the case of an open connection of the non-inverting input, the device would react the same as for the Cold Sensor condition. The internal bias voltage across Z cause the output voltage value defined by V the LM9040 DC gain. The inverting input would still be 7 with Cold Lambda Sensor OUT ...
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... FIGURE 10. V with Open Inverting Input OUT Supply Bypassing For best performance the LM9040 requires a V which is stable and noise free. The same 5V V used for the A/D converter is the recommended V During operation the device will generate current spikes coincident with the clock edges. Inadequate bypassing will ...
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Supply Bypassing (Continued) FIGURE 11. Typical Application 9 01237221 www.national.com ...
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... National does not assume 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. inches (millimeters) unless otherwise noted Order Number LM9040M NS Package Number M14B 2 ...