Output Voltage Swing

Last modified by Microchip on 2023/11/09 08:59

Output Voltage Swing

Figure 1

Output Voltage Swing defines how close the op-amp output can be driven from rail to rail (either power rail, VDD or VSS) under defined operating conditions where the op-amp still can function correctly.

The key to comparing voltage output swing specifications is to determine the amount of current that the amplifier is sinking or sourcing. The smaller the output short circuit current is, the closer the amplifier will swing to the rail. The voltage output swing capability of an op-amp is dependent on the op-amp output stage design and the load current.

In Figure 1 we can clearly see the difference between these concepts such as rail to rail, headroom, VOH, and VOL.

Application Challenge

The input voltage range restrictions are critical in op-amp circuit applications. In a closed-loop configuration, using a voltage beyond the input voltage range sometimes looks like an output limit problem, but in fact, is an input range problem.

Amp'titudes Episode 6 – Rail to Rail Output Stage