lm94021-mda National Semiconductor Corporation, lm94021-mda Datasheet
lm94021-mda
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lm94021-mda Summary of contents
Page 1
... In the lowest gain configuration (GS1 and GS0 both tied low), the LM94021 can operate with a 1.5V supply while measuring temperature over the full −50˚C to +150˚C operating range. Tying both inputs high causes the transfer function to have the largest gain of − ...
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... Typical Application Full-Range Celsius Temperature Sensor (−50˚C to +150˚C) Operating from a Single Battery Cell Ordering Information Order Temperature Number Accuracy ± LM94021BIMG 1.5˚C to ± LM94021BIMGX 1.5˚C to Pin Descriptions Label Pin Type Number GS1 5 Logic Input GS0 1 Logic Input OUT 3 Analog ...
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... Input Current at any pin (Note 2) Storage Temperature Maximum Junction Temperature (T ) JMAX ESD Susceptibility (Note 3) : Human Body Model Accuracy Characteristics These limits do not include DC load regulation. These stated accuracy limits are with reference to the values in the LM94021 Transfer Table. Parameter Temperature GS1=0 Error GS0=0 (Note 8) GS1=0 ...
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... Accuracy limits include line regulation within the specified conditions. Accuracy limits do not include load regulation; they assume no DC load. Note 9: Changes in output due to self heating can be computed by multiplying the internal dissipation by the thermal resistance. Note 10: Source currents are flowing out of the LM94021. Sink currents are flowing into the LM94021. Note 11: Assumes ( 200mV ...
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Typical Performance Characteristics Temperature Error vs. Temperature Supply Current vs. Temperature Load Regulation, Sourcing Current Minimum Operating Temperature vs. Supply Voltage 20108607 Supply Current vs. Supply Voltage 20108604 Load Regulation, Sinking Current 20108640 5 20108606 20108605 20108641 www.national.com ...
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Typical Performance Characteristics Change in Vout vs. Overhead Voltage Output Voltage vs. Supply Voltage Gain Select = 01 Output Voltage vs. Supply Voltage Gain Select = 11 www.national.com (Continued) Output Voltage vs. Supply Voltage 20108642 Output Voltage vs. Supply Voltage ...
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... LM94021 Transfer Function The LM94021 has four selectable gains, each of which can be selected by the GS1 and GS0 input pins. The output voltage for each gain, across the complete operating tem- perature range is shown in the LM94021 Transfer Table, below. This table is the reference from which the LM94021 accuracy specifications (listed in the Electrical Characteris- tics section) are determined ...
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... LM94021 Transfer Function (Continued) LM94021 Transfer Table The output voltages in this table apply for V Temperature (˚C) (mV) (mV) 36 838 1275 37 832 1267 38 827 1258 39 821 1250 40 816 1242 41 810 1234 42 804 1225 43 799 1217 44 793 1209 45 788 1201 46 782 1192 ...
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... Although the LM94021 is very linear, its response does have a slight downward parabolic shape. This shape is very ac- curately reflected in the LM94021 Transfer Table. For a linear approximation, a line can easily be calculated over the (Continued) desired temperature range from the Table using the two ...
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... LM94021 because it does not draw transient currents. For operation in very noisy environments, some bypass capacitance may be required. The capacitance does not need close proximity to the LM94021. The LM94021 has been bench tested successfully with a bypass capacitor as far as 6 inches away. In fact, it can be powered by a properly-bypassed logic gate ...
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... The Gain Select digital inputs can be tied to the rails or can be driven from digital outputs such as microcontroller GPIO pins. In low-supply voltage applications, the ability to reduce the gain to -5.5 mV/˚C allows the LM94021 to operate over the full -50 ˚C to 150 ˚C range. When a larger supply voltage is present, the gain can be increased as high as -13.6 mV/˚ ...
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... Most CMOS ADCs found in microcontrollers and ASICs have a sampled data comparator input structure. When the ADC charges the sampling cap, it requires instantaneous charge from the output of the analog source such as the LM94021 temperature sensor and many op amps. This requirement is easily accommodated by the addition of a capacitor (C depends on the size of the sampling capacitor and the sampling frequency ...
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... English www.national.com Français Tel: +33 ( 8790 5-Lead SC70 Molded Package Order Number LM94021BIMG, LM94021BIMGX NS Package Number MAA05A 2. A critical 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 affect its safety or effectiveness ...