Q: TPS62200 Efficiency Lower Than Expected by 713817

We are looking at using a TPS62202 and are testing a TPS62200 EVM.  The measured efficiencies less than expected from the datasheet.  We are expecting ~93% efficiency from the data sheet but measuring ~89% efficiency on the EVM (VIN = 3.3V, Vout = 1.8V, Iload = 25 – 50 mA).    Do you have any explanation for the slightly lower efficiency numbers expected or do you possibly have any other data for our conditions?


A: Re: TPS62200 Efficiency Lower Than Expected by 10449

This is a common problem caused by an improper test setup.  Please review this application note and implement the technique for measuring efficiency at light loads.  This is the most likely cause of the efficiency discrepancy.  From the application note data, you can see that incorrect measurement technique can significantly reduce the measured efficiency value.  You should also consider the TPS62220 family.  The TPS62220 is a newer generation of the TPS62200.

http://focus.ti.com/general/docs/litabsmultiplefilelist.tsp?literatureNumber=slva236