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LT8490 low power mode below VIN=10V?

The LT8490 datasheet clearly states a minimum SOLAR input voltage of 10V (with low power mode enabled) or 6V (without low power mode) - datasheet page 16.

My question is:
Is it possible to supplement Vin (or some other pin? maybe LDO33?) to achieve a lower minimum panel voltage requirement while maintaining low power mode capability? The datasheet description of "Optional Low Power Mode" (page 29) doesn't explain where the 10V minimum start-up voltage comes from or why it exists. 

For comparison, the LTM8054 datasheet describes how to supplement power to enable operation below the minimum input voltage:

Is there anything similar for the LT8490?

For completeness, my application uses a 7.3Vpmax solar panel to charge a 2S Lipo battery and I would like to use low power mode on the LT8490.


  • When operating below the red line shown in Fig. 5 of the datasheet, the output current could be less than the CC output current setting. This limitation is due to the characteristics of a solar panel, the minimum LT8490 input operating voltage and the required algorithm to properly control the input power of a solar panel. In other words, a little headroom is needed above the LT8490 minimum input voltage to properly manage a solar panel input. If there was another power source to supply Vin with greater than 6V and the input monitoring resistors were properly selected, in theory you would be able to operate down to a lower solar panel input voltage but this has not been investigated to ensure this is robust.