Tps63000 heats up and consumes current

Hi Mohamed:

How many device have you tested? How about change to a new piece and make sure the soldering proper. 

If the issue is still exist, please measure the waveform of Vin, VOut, L1, L2

Hi,

I realized a single board as a prototype, the soldering of the component is clean and I cannot replace the component with another because it is very small, we need the necessary equipments to do this operation.
as soon as I measure the waveform of vout, L1, L2, I will post them in this forum

Hi,

Here is the waveforms requested without load:

supply 4V but the current is 0.46A without load:

L2 waveform :

L1 waveform :

vout waveform the output voltage is correct (3.6V) :

Hi Mohamed:

The waveform is not so clear, may you share the L2 again?  

I highly suspect the IC is damaged already. you can remove all the surrounding components and measure if there is a diode from GND to any other pins. 

Hi,

Thank you for your fast response.

Here is a clear representation of the L2 waveform :

But how the component is damaged while this board is newly designed and it has never been used, and these are the first tests on this board, and how it still gives me the desired voltage 3.6v and there is a high consumption of current without load (500mA)?

When i remove all the surrounding components which pins that i measure if there is a diode from GND?

Hi Mohamed:

According to the L2 waveform, we can find the maximum voltage already exceed the the Absolute Maximum Rating. (Which is 7V). There is the risk. But it may becaused by improper measurement. You can make the GND of the probe closer to the signal, and check if there is any change. 

The L2 waveform of health part and proper measurement is more like a square with less ringing. (Like Fig 10 in datasheet with loading.)

The converter has four switches. In some case, it can still work with partial damage. But I'm not sure if it's for your case....The damage can happen in PCB produce ESD or during the test like the voltage spike I mentioned above. 

You can measure all of the pins if possible. The direction is from GND to the target pin. 

Hi Mohamed:

One more comments:

Can it still regulate Vout=3.6V after changing Vin? Like Vin=3V. 

Hi,

Thank you for your fast response.

Yes I get vout = 3.6v when the vin is 3v but with a consumption of 390mA without load.

Hi Mohamed:

This case becomes more interesting....Do you mistake the L1 L2 signal? In my view, the converter should operate as:

i. If Vin>Vout. Buck mode. L2 equals to Vout, L1 keep switching. 

ii. If Vin<Vout. Boost mode, L1 equals to Vin, L2 keep switching. 

Hi,

I always get the same form of signal whether in buck or boost mode (L1 almost equal to vin and L2 keep switching)
here are the results for vin = 3V :

supply :

L2 :

L1 :

vout :

Hi Mohamed:

L1 is not equal to Vin, there is a obviously gap according to your waveform. 

Have you measured the diode from GND? 

Hi,

I removed all the components connected to the TPS63000 except the inductor, because if I remove it I can't solder it again, we need the necessary equipments to do this operation.
I found a diode between all the other pins (VIN, VINA & EN & PS / SYNC connected, vout, FB) and GND.

HI Mohamed:

So have you tested the L1, L2? That's the critical pins. 

Maybe you can use a hot air to remove the inductance.  

Hi,

The problem is not solved yet, I don't have the necessary equipment to remove and solder the inductance

Hi Mohamed:

It is hard to explain this. When all other components are removed, is there still 7 ohm between inductor and ground? If is, you need to replace a new device and have a try.

Best Regards,

Yichen

Hi,

With all components removed except the inductor, i found a 10ohm between inductor and ground

Hi Mohamed,

The most possible reason is that there is some damage in your device. The possible reason of damage is ESD. The device needs to be replaced with a new one.

Best Regards,

Yichen