anyone who could discuss to me what a rail-to-rail op amp pls? i need it on my portotype >.< ?

Vernon Martorana: here's the circuit, it's for a guitar tunerhttp://img299.imageshack.us/my.php?image=porzio20f... target="_blank">http://img299.imageshack.us/img299/3803/porzio20fi... border="0" alt="Free Image Hosting at www.ImageShack.us" />uploaded @ http://img299.imageshack.us/img299/3803/porzio20fi...thanks...Show more

Raleigh Lufkin: "Normal" OpAmps will saturate and depending on the model sometimes at several volts from the power supply 'rail' voltages."Rail to rail" OpAmps will operate to within 10s of millivolts of their respective power supply voltages. This means you can operate them at lower supply voltages and achieve the same voltages at the output, compared with regular OpAmps. This makes for lower power dissipation.I am not sure what you can get in Manila, but every major manufacturer of linear parts (including OpAmps), makes several rail-to-rail OpAmps. There are so many to choose from, now, that I'm sure you can find *something* that will work! . A guitar tuner is not a 'demanding' application as far as bandwidth and input offsets are concerned.....Show more