Difference between LM2586 and LM2576

Can anyone tell me what the difference between these two switching regulator IC's are??
Thanx.

The LM2586 is designed for increasing the voltage (i.e., "boost" or flyback). The LM2576 is primarily a step-down regulator.

So, if you need a higher voltage than your source, the LM2586 might work for your (depending on other factors). If you need a lower voltage than your source, then use the LM2576.

John