TL431-Q1: Negative voltage output

Lijia Zhu

Expert 5515 points

Part Number: TL431-Q1
Other Parts Discussed in Thread: TL431

Hi team,

Figure 35 is a positive regulator. Could you help to advise how to use this device for a negative voltage regulator?

B&R

Lijia

over 1 year ago

0 Trailokya Rai over 1 year ago

TI__Genius 11401 points

Hi Lija

What is the load current for your application?

Regards

Trailokya

0 Lijia Zhu over 1 year ago in reply to Trailokya Rai

TI__Expert 5515 points

Hi Trailokya,

Max output current is about 100mA.
input voltage is about -21v and output voltage range is -15 to -18v.
B&R
Lijia

0 Trailokya Rai over 1 year ago in reply to Lijia Zhu

TI__Genius 11401 points

Hi Lijia

Thanks for your input. This is not possible with TL431 as you have to take the -ve voltage from anode and you can not break Anode to REF pin loop as the refernce voltage is generated between them.

You can achieve this with LM4041CEM3-ADJ/NOPB as the refernce is generated between cathode and ref pin. You can add BJT at anode to increase the current drive

Regards

Trailokya

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TL431-Q1: Negative voltage output