LDO29300P2MTR

[saran]

We have implemented the following circuit. This matches the application circuit given in datasheet of LDO29300P2MTR.But it does not yield expected output. We need help!!

[Andrew Neil]

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@saran wrote:

 it does not yield expected output. !!

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So what output does it yield ?

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@saran wrote:

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What is the significance of the 5.41A there?

The LD29300 is only a 3A regulator ...

https://www.st.com/en/power-management/ld29300.html 

 

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@saran wrote:

This matches the application circuit given in datasheet 

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Not quite:

You've left the INH pin open.

[saran]

The IC takes an input voltage of 24V/5.4A , expected output is 12V BUT IT GIVES 0V . Also where should I connect the INH pin.

[Andrew Neil]

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@saran wrote:

The IC takes an input voltage of 24V/5.4A 

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The IC takes an input voltage; the current is determined by the load.

 

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@saran wrote:

expected output is 12V BUT IT GIVES 0V . .

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The output depends on R1 - so what do you have that set to?

 

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@saran wrote:

where should I connect the INH pin.

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As the datasheet shows - connect it high for 'ON', or low for 'OFF':

 

[Peter BENSCH]

+1

And for an output voltage of 12V that can be set within narrower limits, I would replace VR1 with 1k and connect an 8.2k resistor in series to VR1. The output voltage should then be adjustable between approx. 11.2V-12.6V.

[saran]

@Andrew Neil

R1 value is 10Kohm ; R2 is 1Kohm

[saran]

@Peter BENSCH

I have shorted pin 1 and pin 2. Still, the output is 0V. If you have any sample circuits for the LDO29300P2MTR, kindly help me solve the issues.

 

[Andrew Neil]

Then check your resistors & wiring.

Perhaps show a good, clear photograph of your setup.

[saran]

@Andrew Neil 

I have attached the images for your reference. Kindly let me know if I have made any mistakes

 

[saran]

@Andrew Neil 

The chip gives expected output 12V but within a fraction of second , voltage drops to 0V.

[saran]

@Andrew Neil 

@Peter BENSCH 

 

Thanks for the help. LD29300P2MTR will work on 2.5 V to 14V only. it will never work greater than 14V. We can use the MIC29302WU 

 

Thanks &Regards,

Saravanan G

[Peter BENSCH]

Sorry, I had also overlooked this during a cursory glance at the data sheet: although the LD29300 can withstand an input voltage of up to 30V, it actually only works up to 14V. This can be found in the data sheet as footnote 1 under table 2:

Above 14 V the device is automatically in shutdown.

Regards
/Peter

[Andrew Neil]

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@Peter BENSCH wrote:

This can be found in the data sheet as footnote 1 under table 2:

Above 14 V the device is automatically in shutdown.

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So it does!

@saran - here:

@saran - always important to understand that these "Absolute Maximum" ratings are not operating specs!