TPS61252 - About current limit at ILIM pin set to VIN

Hi Kanemaru,

I checked with our test engineer and designer, only the 500mA current limit item is guaranteed, the minimun current limit is -20%. In case of ILIM pin tied to Vin, it's not guaranteed that the minimum current limit is 1200mA, but the minimum value should not shift too much.

Is the customer's applicaiton just around 1200mA boundary?

BR

Gene

Hi Gene-san,

 

Thank you for your prompt reply!

According to our customer, the output current hasn't been decided yet.

Therefore, they need the minimum current limit value to estimate "Iout(cl)".

Could you guarantee "ILIM(min)=??mA"?

I'd appreciate if you would examine that.

 

Regards,

Kanemaru

Hi Kanemaru,
I'm a little confused. It seems that your customer decide to choose the IC in the first place and then decide their application of Iout. In my opinion, it should determine the application of Iout first and then choose a appropiate IC.
Anyway, in terms of TPS61252, there's no data to guarantee the minimum current. But I think current limit should not be lower than 1A. In our bench result, with Vout=4.5V, when Vin=2.3V, the max Iout is nearly 500mA, when Vin=4V, it's larger than 1A, just for your reference.

BR
Gene

Hi Gene-san,

 

I apologize for not explaining enough.

Our customer would like to use the following condition.

So, the output current hasn't been completely decided yet.

 

[Condition]

-Vin=2.3V to 4.2V (1cell)

-Vout=6.0V

-Iout=Around 50mA(continuance) , 570mA (peak)

-Cout=22uF

-Cload=47uF*2 + 1uF*2 + 0.1uF*2=96.2uF

 

Regards,

Kanemaru

Hi Kanemaru,
I think TPS61252 can handle your customer's application. TPS61252 is a valley current control device, not peak current control. So 570mA will not trigger current limit.

BR
Gene

Hi Gene-san,

 

I apologize for the late reply.

Thank you for the information.

So, can our customer use TPS61252 at this condition?

Please let me know if you have any concerns about that.

 

Regards,

Kanemaru

Hi Kanemaru,
In terms of current limit, TPS61252 can handle your customer's application.
However in another thread, you just mentioned the min Vin will be 2.1V, where TPS61252 is not suitable. And I'm also cuirious about the application environment and Cload.
as shown in e2e.ti.com/.../399102

BR
Gene