LM9044 Lambda Sensor Interface Amplifier
February 1995
LM9044 Lambda Sensor Interface Amplifier
General Description
The LM9044 is a precision differential amplifier specifically
designed for operation in the automotive environment Gain
accuracy is guaranteed over the entire automotive tempera-
ture range (
b
40 C to
a
125 C) and is factory trimmed prior
to package assembly The input circuitry has been specifi-
cally designed to reject common-mode signals as much as
3V below ground on a single positive power supply This
facilitates the use of sensors which are grounded at the
engine block while the LM9044 itself is grounded at chassis
potential An external capacitor sets the maximum operating
frequency of the amplifier thereby filtering high frequency
transients Both inputs are protected against accidental
shorting to the battery and against load dump transients
The input impedance is typically 1 MX
The output op amp is capable of driving capacitive loads
and is fully protected Also internal circuitry has been pro-
vided to detect open circuit conditions on either or both in-
puts and force the output to a 鈥樷€榟ome鈥欌€?position (a ratio of
the external reference voltage)
Features
Y
Y
Y
Y
Y
Y
Y
Normal circuit operation guaranteed with inputs up to
3V below ground on a single supply
Gain factory trimmed and guaranteed over temperature
(
g
3% of full-scale from
b
40 C to
a
125 C)
Low power consumption (typically 1 mA)
Fully protected inputs
Input open circuit detection
Operation guaranteed over the entire automotive tem-
perature range (
b
40 C to
a
125 C)
Single supply operation
Schematic and Connection Diagrams
TL H 6744 鈥?1
Plastic Chip Carrier Package
Order Number LM9044V
See NS Package Number V20A
Pins 1 3 4 6 8 9 10 11 13 14 16 18 19 are
trim pins and should be left floating
C
1995 National Semiconductor Corporation
TL H 6744
TL H 6744 鈥?6
Top View
RRD-B30M115 Printed in U S A
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