LM9040 Datasheet | National Semiconductor

Description The LM9040 is a dual sensor interface circuit consisting of two independent sampled input differential amplifiers designed for use with conventional Lambda Oxygen Sensors The Lambda Sensor is used for monitoring the oxygen concentration in the exhaust of gasoline engines using catalytic after treatment and will deliver a voltage signal which is dependent on the air-fuel mixture The gain of the amplifiers are internally set and can directly convert the Lambda sensor output voltage to a level suitable for A D conversion in a system using a 5V reference The input mon mode voltage range of each amplifier is g 2V with respect to the IC ground pin This will allow the IC to connect to sensors which are remotely grounded at the engine exhaust manifold or exhaust pipe Each amplifier is capable of independent default operation should either or both of the leads to a sensor bee open circuited Noise filtering is provided by an internal switched capacitor low pass filter as part of each amplifier and by external ponents The LM9040 is fully specified over the automotive temperature range of b40 C to a 125 C and is provided in a 14-pin Small Outline surface mount package Features Y Y Y Y Y Y Y Y Y Y Single 5V supply operation mon mode input voltage range of g 2V Differential input voltage range of 50 m V to 950 m V Sampled differential input Switched capacitor low pass filter Internal oscillator and VBB generator Open input default operation Cold sensor default operation Low power consumption (42 m W max) Gain set by design and guaranteed over the operating temperature range Applications Closed loop emissions control Catalytic converter monitoring Connection Diagram TL H 12372 - 1 Top View Ordering Information LM9040M See NS Package Number M14B C1995 National Semiconductor Corporation TL H 12372 RRD-B30M115 Printed in U S A Absolute Maximum Ratings If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office...