In an open-loop operational amplifier configuration, what happens to the output when the input voltage exceeds the specified input range, leading to output saturation?

When the input voltage in an open‑loop op‑amp goes beyond the device’s allowed input range, the amplifier can no longer produce a proportional output because the internal transistors are driven too far apart. This forces the output to climb until it reaches the supply rails, a state called saturation. In saturation the output voltage is essentially fixed at the positive or negative supply voltage, no longer following the input signal. For example, if a 5 V supply is used and the input suddenly jumps to 3 V, the output will lock near +5 V instead of rising further, indicating the op‑amp has hit its upper limit. Thus, exceeding the input range turns the amplifier into a simple on‑off switch at the rail voltage.