Hello. With such small currents, how should I go about getting accurate efficiency measurements of the TPS610985? I want to load it with 3uA, while supplying it with 1.5V.
Thank you!
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Hello. With such small currents, how should I go about getting accurate efficiency measurements of the TPS610985? I want to load it with 3uA, while supplying it with 1.5V.
Thank you!
Measuring input current through a multimeter gives about 1uA with no load which seems incorrect.
Hello Niclas,
As specified in the datasheet, the quiescent current is measured in no load and no switching condition ( page 6 https://www.ti.com/lit/ds/symlink/tps610985.pdf?ts=1620409179898&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FTPS610985 ) . Let me know if I can help you furthermore.
Kind regards.
I found the document SLVA828, "Calculating and Measuring the No Load Input Current of the Boost Converter" which helped me calculate the quiescent current to 0.5uA, which seems reasonable I guess. My efficiency is slightly lower than expected. I was expecting 85% at a load condition according to the graphs in the datasheets, but got 80% (with the eval board). What can I do to improve it to 85%?
Hi Niclas,
Input current can be measured by the same method introduced in SLVA828. In efficiency measurements, Kelvin four-wire test method is used for accurate input/output measurement. The impact of contact resistor can be reduced by four-wire test method using sense pins of the EVM.
Best Regards,
Eric Yue