1, output voltage range is different
The output voltage range of the dual-supply op amp can reach positive and negative voltage output across zero, while the single-supply op amp cannot. In fact, most of the operational amps can work with either a single power supply or a dual power supply, as long as the power supply voltage is within the appropriate range. For example, the LM324 can work under a single power supply within 32V, and can also work under dual power supplies within the range of ±16V, and the positive and negative power supply voltages are not necessarily symmetrical, and it is also possible to work under 20V and -10V dual power supplies, as long as the voltage difference between the positive and negative power supplies does not exceed 32V.
2. Security
When designing a single power supply circuit, you need to be more careful than a double power supply circuit, usually the voltage supplied by a single power supply is generally 5V, and the output voltage swing of the op amp will be lower. In addition, the supply voltage of the operational amplifier can also be 3V or lower. For this reason, the operational amps used in single-supply circuits are basically Rail-To-Rail amps, thus eliminating the lost dynamic range.
Both the input and output may not be able to withstand the Rail-To-Rail voltage. Although the device is specified as Rail-To-Rail, if the output or input of the op amp does not support rail-to-rail, voltages close to the input or output voltage limits may degrade the function of the op amp, so it is necessary to carefully refer to the data sheet to see whether the input and output are both rail-to-rail. In this way, the function of the system will not be degraded.
There is only one op amp inside the single op amp, and there is an op amp with the same parameters inside the double op amp (better consistency). The performance of the same series of single op amp is basically the same as that of the two op amps inside the double op amp. In general, the power consumption of two single op amps is slightly larger than that of a double op amp. If the crosstalk between the two amps is required to be small (for example, for audio, the degree of call separation), then it is better to use two single amPs than one double one.