Op amp power supply decoupling bypass measures

Each integrated operational amplifier power lead should generally adopt decoupling bypass measures, that is, a high-performance capacitor is connected from the power lead end to the ground, as shown in the figure. The high-frequency bypass capacitor in the figure can usually be a ceramic capacitor with excellent high-frequency performance, with a value of about 0.1μF. Or a tantalum capacitor of 1μF. The internal inductance values ​​of these capacitors are small. In high-speed applications of operational amplifiers, bypass capacitors C1 and C2 should be connected to the power pins of the integrated operational amplifier, and the leads should be as short as possible, so that a low-inductance ground loop can be formed. When the gain-bandwidth product of the amplifier used is greater than 10MHz, more stringent high-frequency bypass measures should be adopted. At this time, RF bypass capacitors should be selected, such as 0.1μF disc ceramic capacitors, and a pair of tantalum capacitors (C1 and C2) should be added to each printed board or every 4 to 5 integrated chips. For general integrated chips, the bypass requirements are not high, but they cannot be ignored. It is usually best to add a set of bypass capacitors for every 4 to 5 devices. Regardless of the number of integrated circuit devices used, at least one set of bypass capacitors should be added to each printed board.