How to get +/-12V power source?

Hi Yu-Hung,

Thanks for reaching out and considering TI for your solutions.

There are a number of ways to create the two rails your application requires. What is the input voltage range for the application Are there any regulation specifications for each rail?

1. For a single chip solutions the following topologies

- Flyback  /Flybuck (LM5160)

2. Negative Rail

Most Buck Converter. I will loop in the appropriate engineer for these devices

3. Positive Rail

Almost any boost converter. The LM2698 might be a good solution. I will also loop in the appropriate engineers

Thanks,

Garrett

Hello Garrett,

Thanks for your help.

The power source of system uses 2 lithium battery in series only. (3.7V+3.7V=7.4V).

My application is to power the sensors and read analog output by ADS1281.

Hope the noise is not too big.

YHH

Hello Jasper,

I try to make a demo for that.

The maximum output current seems depend on the diode.

I saw a lot of formula to calculate.

Do you know what is Ilim = overcurrent limit and IP = inductor peak to peak ripple current?

YHH

Hi Yu-Hung

Ilim is the current limit current of the device normally, which is 1A for TPS61170.

IP seem to be the peak current of the inductor. where did you find IP?

Hello Jasper,

In the datasheet of TPS61170. (9.2.2.2 Maximum Output Current)

What do you think about the circuit I shown? Is it ok?

Hi Yu-Hung

the loading in this application is still far from the maximum output current.

the schematic is good.

Thank you Jasper.