The LM2904 IC consists of two independent, high gain, internally frequency compensated operational amplifiers. LM2904 IC is specifically designed to operate from a single power supply over a wide range of voltages.
The LM321 is a low power single Operational Amplifier with a high unity gain frequency and a specified 0.4-V/µs slew rate, the quiescent current is only 430-µA/amplifier (at 5V). The LM321 is available in SOT-23 packages.
The LM1558 are general purpose dual operational amplifiers. The two amplifiers inside this single IC share a common bias network, and power supply leads. Otherwise, their operation is completely independent.
The TDA2822 is a dual low power audio amplifier in an 8-Pin plastic dual in-line package. This IC comes with features like low crossover distortion, low quiescent current, and supply voltage range of this IC is 3V to 15V.
The OP07 is an Ultralow Offset Voltage ((75μV maximum) Operational Amplifier with low input bias current (±4nA) and high open-loop gain (200 V/mV). The OP07 is available in epoxy 8-lead PDIP and 8-lead narrow SOIC packages.