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LM358N
The LM358 is a low-power dual operational amplifier integrated circuit, originally introduced by National Semiconductor. It uses a single power supply from +3 to +30 volts for Voltage common collector, VCC (though some variants go higher, such as 36 volts for the LM358B). Input voltage can range from −0.3 volts to VCC. Small negative input voltages below Ground (electricity), ground (GND) are acceptable because the bipolar junction transistors at the input stage are configured such that their base-emitter junction voltage provides just enough voltage differential between the collector and base for the transistors to function. History After the development of the 741 and its dual and quad derivatives, National Semiconductor's Russell and Frederiksen developed an amplifier design suitable for low-voltage single supply packages, hinging on an input stage gm reduction technique due to James Solomon.James Solomon, “The Monolithic Operational Amplifier: A Tutorial St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bandgap Voltage Reference
A bandgap voltage reference is a voltage reference circuit widely used in integrated circuits. It produces an almost constant voltage corresponding to the particular semiconductor's theoretical band gap, with very little fluctuations from variations of power supply, electrical load, time, temperature (, they typically have an initial error of 0.5–1.0% and a temperature coefficient of 25–50 ppm/ °C). David Hilbiber of Fairchild Semiconductor filed a patent in 1963 and published this circuit concept in 1964. Bob Widlar, Paul Brokaw and others followed up with other commercially-successful versions. Operation The voltage difference between two p–n junctions (e.g. diodes), operated at different current densities, is used to generate a current that is ''proportional to absolute temperature'' (''PTAT'') in a resistor. This current is used to generate a voltage in a second resistor. This voltage in turn is added to the voltage of one of the junctions (or a third one, in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
