Hi Kevin:

If the load is light, the converter will work in burst mode. The Vout will be around 3.4V.

Minqiu:

When the current is 20-30 mA, the voltage drops.

But this power consumption, there is no need to use this chip;

using this chip is to have low power consumption function,

what chip can be recommended

Hi Kevin:

Do you mean the Vout drop with 20mA load? Is it in startup? TPS61098 should have such current capability if the design is proper. 

And TPS61099 can be alternative. 

Minqiu:

My use condition is: input 2.2V, output 3.3V, current 1mA, but low power consumption is required.

Now the output voltage of tps680981 under this condition will rise to 3.49v,

please recommend which model is more suitable.

Hi Kevin,

could you share the layout? sometimes, bad layout would cause unstable output voltage.

also measure the VIN and VOUT waveform if possible.

Hi Kevin,

I don't see C27~C29 in the image. please place a 10uF capacitor as close to the IC as possible. refer to the datasheet to understand how to build layout for the boost