REF3330: Vin Rise time

KJ LEE

Prodigy 10 points

Part Number: REF3330

Tool/software:

Is there a restriction on the rise time of the input power?

Most operate normally regardless of VIN rise time, but Only one has an VOUT No Output, HIZ phenomenon.

The datasheet does not show anything regarding the VIN rise time.

Should I regard it as a chip defect?

OSC CH2: VIN, CH3:VOUT

1.VIN = 3V, Rise time : 100msec -> VOUT No Output, HIZ

2. VIN = 3V, Rise time : 10msec -> Good work

27 days ago

0 Jackson Wightman 26 days ago

TI__Expert 8940 points

Hello,

If you are using REF3330 which has a 3.0V output, 3.0V input is too low. It also seems that the green trace in these figures is showing an input voltage of 2.5V, not 3.0V.

Can you please run this experiment again where the input voltage is at least VOUT + VDO? For REF3330, I would recommend an input voltage of at least 3.2V.

Thanks,

Jackson

0 KJ LEE 26 days ago in reply to Jackson Wightman

Prodigy 10 points

The VIN was tested again at 3.3V

1.VIN = 3.3V, Rise time : 110msec -> VOUT No Output, HI-Z

2. VIN = 3.3V, Rise time : 10msec -> VOUT 3.0V Good work

why.......??

0 Jackson Wightman 25 days ago in reply to KJ LEE

TI__Expert 8940 points

We are looking into this and will let you know once we have more details.

0 Jackson Wightman 23 days ago in reply to Jackson Wightman

TI__Expert 8940 points

Hello,

We are not seeing the issue described above on our bench, and we have not been able to reproduce it. If you have a schematic, I can review that, but otherwise, I have no further suggestions.

For any additional details, please see this forum:

REF3330: Inquiries regarding the issue that Vout does not come out when starting REF3330

Thanks,

Jackson

0 KJ LEE 21 days ago in reply to Jackson Wightman

Prodigy 10 points

Below is the circuit tested.

Here too, it cannot be reproduced except with that problematic sample.
Is this sample a defective product?
I want to know if analysis is needed to confirm the defect.

0 Jackson Wightman 20 days ago in reply to KJ LEE

TI__Expert 8940 points

Hello,

I don't see any obvious issues with this schematic.

KJ LEE said:
Is this sample a defective product?
I want to know if analysis is needed to confirm the defect.

This is not handled on this forum. If this is an action you wish to take, please contact your local TI representative.

Thanks,

Jackson

Power management

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REF3330: Vin Rise time