December 6, 2007
LM94022/LM94022Q
1.5V, SC70, Multi-Gain Analog Temperature Sensor with
Class-AB Output
General Description
The LM94022 is a precision analog output CMOS integrated-
Appliances
Disk Drives
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Games
circuit temperature sensor that operates at a supply voltage
as low as 1.5 Volts. A class-AB output structure gives the
LM94022 strong output source and sink current capability for
driving heavy loads. For example, it is well suited to source
the input of a sample-and-hold analog-to-digital converter
with its transient load requirements. While operating over the
wide temperature range of −50°C to +150°C, the LM94022
delivers an output voltage that is inversely porportional to
measured temperature. The LM94022's low supply current
makes it ideal for battery-powered systems as well as general
temperature sensing applications.
Features
LM94022Q is AEC-Q100 Grade 0 qualified and is
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manufactured on an Automotive Grade Flow.
Low 1.5V operation
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Push-pull output with 50µA source current capability
Four selectable gains
Very accurate over wide temperature range of −50°C to
+150°C
Two logic inputs, Gain Select 1 (GS1) and Gain Select 0
(GS0), select the gain of the temperature-to-voltage output
transfer function. Four slopes are selectable: −5.5 mV/°C,
−8.2 mV/°C, −10.9 mV/°C, and −13.6 mV/°C. In the lowest
gain configuration (GS1 and GS0 both tied low), the LM94022
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 −13.6 mV/°C for maximum temperature sensitivity.
The gain-select inputs can be tied directly to VDD or Ground
without any pull-up or pull-down resistors, reducing compo-
nent count and board area. These inputs can also be driven
by logic signals allowing the system to optimize the gain dur-
ing operation or system diagnostics.
Low quiescent current
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Output is short-circuit protected
Extremely small SC70 package
Footprint compatible with the industry-standard LM20
temperature sensor
Key Specifications
■ꢀSupply Voltage
1.5V to 5.5V
5.4 μA (typ)
±50 μA
■ Supply Current
■ Output Drive
■ꢀTemperature
Accuracy
20°C to 40°C
-50°C to 70°C
-50°C to 90°C
-50°C to 150°C
±1.5°C
±1.8°C
±2.1°C
±2.7°C
Applications
Cell phones
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■ꢀOperating
Temperature
Wireless Transceivers
−50°C to 150°C
Battery Management
Automotive
Connection Diagram
Typical Transfer Characteristic
SC70-5
Output Voltage vs Temperature
20143001
Top View
See NS Package Number MAA05A
20143024
© 2007 National Semiconductor Corporation
201430
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