Resistor value

[j.blokesz1]

Hello,
I have a problem, could someone check and tell what is the value of resistor marked with the red circle on the photo? I don't have it on my PCB. I think that this resistor sets the output voltage of the step down converter which is placed next to this resistor. Actually the output voltage is 1.56V but I don't know what level should it really be.
And the last question. The Ambarella chip is getting quickly hot. Do You have the same or my chip is broken?
Please help me.
Greetins

 

[jason]

Hello,
I have a problem, could someone check and tell what is the value of resistor marked with the red circle on the photo? I don't have it on my PCB. I think that this resistor sets the output voltage of the step down converter which is placed next to this resistor. Actually the output voltage is 1.56V but I don't know what level should it really be.
And the last question. The Ambarella chip is getting quickly hot. Do You have the same or my chip is broken?
Please help me.
Greetins

Since DJI does not supply schematics nor mark their components it's anybody's guess as to what that component is as it could be an inductor or a resistor. So you have two choices either send it in for repair or buy a new board.

 

[j.blokesz1]

Thank You for quick answer. Unfortunately this PCB as spare part is quite expensive. Maybe I can calculate the value of this resistor (it is used as a voltage divider with the second resistor to set the output voltage of the step down converter. I only need the value of VDD (there is a test point called VDD on the opposite site of PCB).

 

[jason]

Thank You for quick answer. Unfortunately this PCB as spare part is quite expensive. Maybe I can calculate the value of this resistor (it is used as a voltage divider with the second resistor to set the output voltage of the step down converter. I only need the value of VDD (there is a test point called VDD on the opposite site of PCB).

With over 20 years repairing electronic equipment I can say you have no idea of what you are doing and should leave it to someone who does.

 

[j.blokesz1]

I can say you that I am an electronician and I know what I am doing. And I can see that You didn't understand my a last answer. I was asking about specific parameters not stupid opinion. So please if You don't have time or can't measure that parameters please stop writing Your thoughts in the topic. Thanks

 

[Technical Bob]

The pair of you need to get a room and work out your stress . . . .

 

[With The Birds]

VDD is typically IC power supply voltage. Simply find a supply V+ pin on a nearby IC and look up the nominal supply voltage. That won’t help you calculate a resistor value, it may be a reference resistor but it won’t be a voltage divider. 1.2, 1.8 & 3.3V would be typical and expected.

You don’t need to be so snarky, I don’t know what an elecronician is (never heard the term) but if you are some form of electrical engineer or technician you would know that often the best advice to give people where there is a chance they might not have the skills to diagnose and repair is to take it to someone with the right tools and skills. I’m not saying you can’t fix it yourself, A lot do struggle with SMD rework, I have seen some horrendous butchering.

 

[j.blokesz1]

Thank You for Your answer.
Sorry but I asked a specific question so I'm looking forward to specific answer not something like jasons answer. So please don't be surprised with my reaction.
Unfortunately these power lines (VDD and VDDA) are used by Ambarella A9 chip only which datasheet is impossible to find.
This resistor is a part of step down converter TLV62130. Here is its datasheet: http://www.ti.com/lit/ds/symlink/tlv62130.pdf. It is placed between FB and VOUT on the first circuit in the datasheet. The second resistor is 10kohm so using the formula 6 from page 14 I'm able to compute the value of second resistor. Of course I have to know what voltage should I set.

 

[With The Birds]

Thank You for Your answer.
Sorry but I asked a specific question so I'm looking forward to specific answer not something like jasons answer. So please don't be surprised with my reaction.
Unfortunately these power lines (VDD and VDDA) are used by Ambarella A9 chip only which datasheet is impossible to find.
This resistor is a part of step down converter TLV62130. Here is its datasheet: http://www.ti.com/lit/ds/symlink/tlv62130.pdf. It is placed between FB and VOUT on the first circuit in the datasheet. The second resistor is 10kohm so using the formula 6 from page 14 I'm able to compute the value of second resistor. Of course I have to know what voltage should I set.

Fair enough re your response, you will see some instances like that around here.

The voltages I quoted above I’m pretty sure are for the A9. I will have a dig around and PM you the datasheet if I can find it.