Electronic – Alternative to inductor on IC

Should i buy it instead of using winding inductor

Probably not if it's intended as the resonating coil in a 100MHz FM transmitter. Chances are this inductor will have a self-resonant-frequency below your transmission frequency and then it will behave like a capacitor. Also there are the inductor's losses to consider - basically you need a fairly high Q at your operating frequency but the small ferrite the inductor may be wound on may have high losses over (say) 500kHz.

If you are using the inductor at non-critical frequencies in non-critical areas of the circuit then maybe it'll be OK. My advice as usual on these type of questions, read the data sheet and understand that the inductor has self-resonance due to interwinding capacitance and losses that may rise exponentially with frequency.

The major disadvantage of a gyrator is that it needs DC power and a DC bias to set the circuit up correctly. The advantage of an inductor of course is that this is not needed.

Another disadvantage of a gyrator is that they are all (from what I've seen of the simple transistor/op-amp type) all ground referenced at one end of the inductor i.e. if you wanted an inductor that was ungrounded on both pins then it becomes a lot more complex.

Many inductors are used in power applications (such as switch mode power supplies). In simple words, gyrators are useless in these applications.

The main area that I see a lot of gyrators used is in audio graphic equalizers where a low power and low to medium Q factor is needed. Also frequencies are moderately low i.e. limited to no-more than 20kHz.