What Are The Types Of Operational Amplifiers?

The type of operational amplifier can be divided into general type, low temperature drift type, high speed type, high resistance type, high voltage and high power type, low power type, programmable control type according to the difference in the input/output voltage range, can be divided into dual power operational amplifier, single power operational amplifier, rail to rail operational amplifier.
Universal type
General-purpose operational amplifiers are designed for general-purpose purposes. The main features of this kind of device are low price, large product quantity and wide range, and its performance index can be suitable for general use. Examples μA741 (single op amp), LM358 (double op amp), LM324 (four op amp) and LF356 with FET as input stage all belong to this. They are the most widely used integrated operational amplifiers.
High resistance type
This type of integrated operational amplifier is characterized by very high differential mode input impedance, very small input bias current, generally rid>1GΩ~1TΩ, IB for a few picoamps to dozens of picoamps. The main measure to achieve these indexes is to make use of the high input impedance of the field effect tube (FET) to form the differential input stage of the op AMP. Using FET as input stage not only has high input impedance and low input bias current, but also has the advantages of high speed, wide band and low noise, but also has large input offset voltage. Common integrated devices are LF355, LF347 (four-op amplifier) and CA3130, CA3140 with higher input impedance.
Low temperature bleach type
In automatic control instruments such as precision instruments and weak signal detection, it is always hoped that the offset voltage of the operational amplifier is small and does not change with the change of temperature. Cryobleached operational amplifiers are designed for this purpose. At present, the commonly used high precision and low temperature drift operational amplifiers are OP07, OP27, AD508 and the chopped zero stable low drift device ICL7650 composed of MOSFET.
High-speed type
In fast A/D and D/A converters and video amplifiers, the conversion rate SR of integrated operational amplifiers must be high, and the unit-gain bandwidth BWG must be large enough, such as general-purpose integrated operational amplifiers are not suitable for high-speed applications. The high speed operational amplifier is characterized by high conversion rate and wide frequency response. Common operational amps are LM318, μA715, etc., whose SR=50~70V/us,BWG>20MHz.
Low-power type
Because the [sensitive word] advantage of electronic circuit integration is that complex circuits can be small and lightweight, so with the expansion of the application range of portable instruments, it is necessary to use low power voltage supply and low power consumption of operational amplifiers. Commonly used operational amplifiers are TL-022C, TL-060C, etc., the operating voltage is ±2V~±18V, and the consumption current is 50~250μA. At present, the power consumption of some products has reached the μW level, such as the power supply of the ICL7600 is 1.5V, the power consumption is 10mW, and a single battery can be used to supply power.
High voltage and high power type
The output voltage of an operational amplifier is mainly limited by the power supply. In an ordinary operational amplifier, the [sensitive word] value of the output voltage is generally only tens of volts, and the output current is only tens of Ma. In order to increase the output voltage or increase the output current, an auxiliary circuit must be added outside the integrated op amp. High voltage and high current integrated operational amplifiers can output high voltage and high current without any additional circuit. For example, the power supply voltage of the D41 integrated op amp can reach ±150V, and the output current of the μA791 integrated op amp can reach 1A.
Programmable control type
In the use of instruments and meters will involve the problem of range. In order to get a fixed voltage output, it is necessary to change the amplifier magnification. For example, an operational amplifier has a magnification of 10 times, when the input signal is 1mv, the output voltage is 10mv, when the input voltage is 0.1mv, the output is only 1mv, in order to get 10mv, the magnification must be changed to 100. Programmed operational amplifier is produced in order to solve this problem. For example, PGA103A changes the magnification by controlling the level of pin 1 and 2.