LM25143-Q1: LM25143 Low power mode

xianfeng zhang

Part Number: LM25143-Q1
Other Parts Discussed in Thread: LM25143, LM5137-Q1, LM5143-Q1

Tool/software:

We use LM25143 to power QAM8255 on the Qualcomm 8255 platform. In STR mode, how should LM25143 be set for low power consumption? We are now turning off EN2 and leaving only EN1 on, but the STR current is still exceeding the standard. Are there any other settings?

6 months ago

0 Onkar Bhakare 6 months ago

TI__Genius 15156 points

Hi Xianfeng

LM25143 has ultra-low Iq mode and can be enabled by connecting MODE to AGND through a 10-kΩ resistor.

Hope this helps

Thank you

Regards

Onkar Bhakare

0 Timothy Hegarty 6 months ago in reply to Onkar Bhakare

TI__Guru 74342 points

Hi Xianfeng,

Is this a 2-phase, single-output design with MODE tied high? If so, there is no actual sleep mode for ultra-low Iq in this configuration. If this is critical for a 2-phase circuit implementation, take a look at the LM5137-Q1 80V controller as a possibility.

Regards,

Tim

0 xianfeng zhang 6 months ago in reply to Timothy Hegarty

Prodigy 20 points

According to Qualcomm's reference design, it is designed as a Single-Output Interleaved Operation with an output of 3.3V. MODE and FB1 connected to VDDA,FB2 connected to GND

0 xianfeng zhang 6 months ago in reply to xianfeng zhang

Prodigy 20 points

Hi Tim,

in the single-output interleaved operation mode, EN1 ON,EN2 is turned off. What is the power consumption of 25143?

0 Timothy Hegarty 6 months ago in reply to xianfeng zhang

TI__Guru 74342 points

Hi Xianfeng,

I will have to check on this and get back to you.

Regards,

Tim

0 xianfeng zhang 6 months ago in reply to Timothy Hegarty

Prodigy 20 points

Hi Tim,

Is there an update?

0 xianfeng zhang 6 months ago in reply to Timothy Hegarty

Prodigy 20 points

Hi Tim,

If we use Independent Dual-Output Operation mode, MODE connect 10 kΩ to AGND,FB1 and FB2 connect to VDDA, VOUT1 and VOUT2 output 3.3V.

Is there a latent risk if the two are used together for Qualcomm 8255?

Best regards

xianfeng

0 Timothy Hegarty 6 months ago in reply to xianfeng zhang

TI__Guru 74342 points

Hi Xianfeng,

No need for the 10kΩ - just connect MODE to GND to setup a dual-output configuration. Then drive COMP2 with a buffer from COMP1.

Alternatively and much easier, go ahead and use the LM5137-Q1 controller (the next gen of the LM5143-Q1).

Regards,

Tim

0 xianfeng zhang 5 months ago in reply to Timothy Hegarty

Prodigy 20 points

Hi Tim,

thank you for your reply!

I have another question, After changing LM25143 to dual independent outputs,EN1must be pull up to 12V, unable to control with MCU GPIO(3V3),why?

best regards

0 Timothy Hegarty 5 months ago in reply to xianfeng zhang

TI__Guru 74342 points

The EN threshold should be ~1.5V, so it should work fine with 3.3V logic signal.

Regards,

Tim

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LM25143-Q1: LM25143 Low power mode