As industrial and automotive equipment becomes more sophisticated and application control requirements become more precise, environmental sensors are increasingly used to quantify temperature, pressure, and gas concentrations, such as carbon dioxide, to drive a sustainable society. However, sensor signals are so small that amplification is necessary. If a general-purpose operational amplifier with a 1 mV equilibrium voltage is used to amplify the sensor signal by a factor of 1000, for example, the equilibrium voltage also increases by the same amount, resulting in a 1 V (1000 mV) voltage error in the output signal. At the same time, temperature drift of the input equilibrium voltage, which varies with temperature and time, is difficult to compensate for.
In response to this situation, ROHM has developed a zero-drift operational amplifier that solves these problems by leveraging proprietary analog circuit technology refined over many years. The LMR1002F-LB is ROHM's first zero-drift operational amplifier to use the chopper amplifier method. Unlike conventional low-compensation operational amplifiers that exhibit a typical input balance voltage of 150 µV (max.), ROHM's new product limits the input balance voltage to only 9 µV (94% lower). This eliminates the need for peripheral components or software to adjust the input balance voltage, thereby reducing design labor hours and costs. Furthermore, the temperature drift of the input balance voltage is only 0.05 µV/°C (max.) over the operating temperature range of -40°C to +125°C, the lowest among ROHM operational amplifiers. Precise amplification of sensor signals, unaffected by environmental changes such as temperature, contributes to high-precision control of industrial equipment in factories. This, combined with a wide operating voltage range of 2.7 V to 5.5 V and rail-to-rail input/output, makes it ideal for a wide variety of industrial applications.
In the future, ROHM will continue to improve the performance and expand its range of zero-drift operational amplifiers. Furthermore, ROHM will work to enhance the performance of its operational amplifier ranges by reducing noise and offset, while simultaneously increasing energy efficiency and expanding the range of power supply voltages demanded by the automotive and industrial equipment markets. The overall goal is to contribute to solving societal problems through more precise application control.
Product range
Application examples
• Industrial equipment: power control inverters, photovoltaic inverters, battery storage control, pressure gauges, flow meters, temperature controllers, gas detectors, etc.
• Consumer applications: refrigerators, washing machines, air conditioning equipment, etc.
