Application for 5V boost to 75V,25mA/200V,10mA

chentsu chung

Mastermind 6180 points

Other Parts Discussed in Thread: LM3478, LM5122, LM3481, PMP20183

Hi TI,

Here are two application:

-- input: 5V output: 75V/25mA

-- input: 5V output: 200V/10mA

1. I have found LM3478 and LM5122, could you help to check if these are good for the request or not, or any better solution for this, thank you.

2. There is a TI design, PMP20183, using LM3481, is it possible to use LM3478 and LM5122 to replace?

C.T.

over 6 years ago

0 Youhao Xi over 6 years ago

TI__Guru* 78110 points

Hi Chentsu,

Thank you for your interests. I would recommend LM3481, a lower cost solution. You don't have to use the LM5122 which is synchronous boost controller for such high step up ratio and 25mA application. Yes you can refer to the PMP20183.

Thanks,
Youhao Xi

0 chentsu chung over 6 years ago in reply to Youhao Xi

Mastermind 6180 points

Hi Youhao,

Thanks for your response, but for -- input: 5V output: 75V/25mA, LM3481 looks like can't support such duty, am I right?

0 chentsu chung over 6 years ago in reply to chentsu chung

Mastermind 6180 points

Hi Youhao,

Is there any update? Thank you.

0 Youhao Xi over 6 years ago in reply to chentsu chung

TI__Guru* 78110 points

Hi Chentsu,

There are charge pump stages to step the first boost stage output voltage produced by the max duty (see the PMP20183), and importantly, you can operate the circuit in DCM that would not require the max duty. Note DCM is only reasonable for low load current. If the load is high, DCM will have huge peak switching current, not a favorable option.

Thanks,
Youhao

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Application for 5V boost to 75V,25mA/200V,10mA