Tps61086EVM doesn't go to 0V.

Thanks for your prompt reply.

it is a battey powerded device so the output must go to zero. I test with the BQ24075 if the Output goes to zero, by the specs he must do that but in my eval board it won't work.

I must check if there is a BQ24075 on the eval board, by the specs of the board it is.

For the 5 V output I need 2,5 Amps so I don't if there is a part in the range of the buck converter that can deliver 2.5 Amps.

as I say I must check the eval board for the right part because in the specs talk they that you can power down the out put sothat is maybe also a solution two power down out aplication.

I will look also on your websit for a solution.

If you are going from a Li-Ion battery to 3.3V and 5V, I recommend the TPS63000 series of devices.  With these devices you can discharge your battery more (down below 3.3V) and still maintain a regulated 3.3V.

The TPS63020, which was just released this week, will allow the output to go 0V when it is off.  It is our highest current boost converter that has the output disconnect that you want.

Hello Chris,

I must also make a solution for the 12Voltage, or take the 12 Voltage of the TPS63020. I need 1 A by 12V.

ps or shutdown the power rail with the BQ24075.

It is best to take the 12V directly off of the charger output.  At 3V on the OUT pin and 90% efficiency, this is 4.4A average input current to the boost converter.  For this much power, you need to use an external switch boost, such as the TPS40210.  If you can break up the 12V into two 0.5A pieces, then you can look at internal switch parts, such as the TPS61175 or your TPS61087.  In any case, the best way to turn off the output is with a PFET in series with the input to whichever boost you choose.  Just pull the PFET gate high to open the connection to the boost and turn off the 12V.

Hello Chris,

I go back to the basic why I choose this parts. we did some measerment and this are the power consumtion that I need.

-              3,3V        2A

-              5V           2A

-              12V         0,5 A

So no Imust choose where we take the primaie power from and how we put them to ) when the application is off.

With a 3V battery, that is roughly 8A of input current to the various loads.  The bq24075 is rated for 4.5A from BAT to OUT.  For that much power, you need to look at an external FET switching charger, such as the bq24610 family.  What is your input source to the charger?  Will these loads always be running?

For maximum efficiency, each rail should be sourced separately from the OUT pin of the charger.  For the 3.3V, I would definitely use the tps63021.  For the 5V, the tps63020 or tps61030 almost get you 2A at 3V in.  You can either reduce the load current or raise the minimum Vin (discharge your battery less) if you want to use either of those parts.  The next step up is the TPS61087.  For the 12V output, the TPS61087 will work.  So, to meet your above specs, I recommend 2x TPS61087 for 5V and 12V, with a PFET between OUT and the input to both tps61087s.

Hello Chris,

the input from I like to make 5V.

and thanks for advise.

I will look to it this weekend.