LM5148-Q1: Wants to know whether LM5148-Q1 can output negative Vout.

Koki Tsushima

Part Number: LM5148-Q1
Other Parts Discussed in Thread: LM5145, LM61495, LM25148, TPS51375

Tool/software:

Hi experts,

My customer found this material. "Create an Inverting Power Supply From a Step-Down Regulator http://www.ti.com/lit/slva317 ".

I understand most of buck converter can output negative Vout theoretically, but is this understanding correct? For example, can LM5148-Q1 be done?

In detail, customer seeks following situation; Vin：max. 12V, Vout：-5V , Iout：max. 10A. Do you have some recommendation which this can be met.

Best,

Koki Tsushima

8 months ago

0 Taru Kapoor 8 months ago

TI__Genius 11715 points

Hi Koki San,

Yes, it is possible to implement an inverting buck boost using a buck controller.

In fact, the LM5145 also has a quick start calculator for an IBB topology: https://www.ti.com/product/LM5145#design-tools-simulation. (Although this is a Voltage Mode Buck Controller).

Since your Max Input Voltage is 12V - you can look at other controllers with lower max Vin (like LM25148) and even devices with integrated FETs like LM61495, TPS51375, etc.

Thanks,

Best Regards,

Taru

0 Koki Tsushima 8 months ago in reply to Taru Kapoor

TI__Intellectual 875 points

Hi Taru,

Nice. I asked about LM5148-Q1. How about this?

Best,

0 Taru Kapoor 8 months ago in reply to Koki Tsushima

TI__Genius 11715 points

Yes

It will work

0 Koki Tsushima 8 months ago in reply to Taru Kapoor

TI__Intellectual 875 points

Hi Taru,

Do you have some update?

Best, Koki

0 Taru Kapoor 8 months ago in reply to Koki Tsushima

TI__Genius 11715 points

Hi Koki,

As I mentioned in my last reply, LM5148-Q1 will work here.

Thanks,

Best Regards,

Taru

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LM5148-Q1: Wants to know whether LM5148-Q1 can output negative Vout.