Question

Find the expression for full power response.

(a) fmax(Hz) =(slew rate×10^6)/(6.28×Vm)

(b) fmax(Hz) =slew rate /(628×10^6×Vm)

(c) fmax(Hz) =(slew rate×Vm×10^6)/6.28

(d) fmax(Hz) =(6.28×Vm× 10^6)/ slew rate

The question was posed to me during an online exam.

This intriguing question originated from Slew Rate in portion Practical Limitations of Op Amp Circuits of Linear Integrated Circuits

Answer 1

Full power response frequency (Fmax) is the maximum frequency at which an op-amp can produce its full output voltage with a given slew rate.

The expression for full power response is:

Fmax(Hz) = (Slew rate × 10^6) / (2π × Vm)

Or alternatively:

Fmax(Hz) = (Slew rate × 10^6) / (6.28 × Vm)

Where Vm is the maximum output voltage amplitude.

Answer: (a) fmax(Hz) = (slew rate×10^6)/(6.28×Vm)

Answer 2

The full power response expression for an op-amp is the maximum output voltage that can be achieved at a given frequency before slew rate limiting occurs. The correct answer is (a) fmax(Hz) = (slew rate x 10^6)/(6.28 x Vm). This expression represents the maximum frequency at which the op-amp can provide full output voltage swing without being limited by slew rate. The factor 6.28 is 2 times pi (approximately), and Vm is the maximum output voltage amplitude. This relationship is critical for understanding the bandwidth-dependent output amplitude of op-amp circuits.