TIDA-010030: about the Isolated power supply

user6501051

Intellectual 825 points

Part Number: TIDA-010030
Other Parts Discussed in Thread: SN6501

Dear TI expert,

I designed an isolated 5V output with reference to TIDA-010030 isolated power supply. The circuit is as follows:

but the TLV70450DBVT is very hot and then damaged. if the transformer select not right?

according to sn6501 datasheet in page 17,

the turn ration

so =1.031*(0.2+1.1+5.02)/(4.95-3*150/1000)=2.426

1.1 is VDO max

over 3 years ago

0 Ryan Tan over 3 years ago

TI__Expert 3356 points

Hi,

Please refer Table 8-3. Recommended Isolation Transformers Optimized for SN6501 in SN6501 datasheet to choose the recommended transformers.

I don't think you need 2.426 turn ration for a 5V-5V solution (you need to choose all the parameters based on your real use cases, rather than the datasheet abs value).

If you LDO is very hot, you may want to measure the input voltage, output voltage, output current to check if the voltage and current are what you expect.

Best Regards,

Ryan Tan

0 user6501051 over 3 years ago in reply to Ryan Tan

Intellectual 825 points

i use the component the same with TIDA-010030, push-pull transformer use WE 760390012

0 Ryan Tan over 3 years ago in reply to user6501051

TI__Expert 3356 points

760390012 turn ration is 1:1.1.

It is good enough. Do you test LDO input and output?

0 user6501051 over 3 years ago in reply to Ryan Tan

Intellectual 825 points

i will change, and test, i check the TIDA-010030 use 760390012

0 Ryan Tan over 3 years ago in reply to user6501051

TI__Expert 3356 points

You are right. TIDA-010030 uses 760390012.

0 user6501051 over 3 years ago in reply to Ryan Tan

Intellectual 825 points

Is it the wrong choice? Because there is no LDO to choose this model

0 Ryan Tan over 3 years ago in reply to user6501051

TI__Expert 3356 points

You will find that the main difference is turn ratio. So if your LDO and diodes have very low drop voltage or your load can withstand the drop, it is fine to choose a different turn ratio here. And of course, you can choose 760390014.

0 user6501051 over 3 years ago in reply to Ryan Tan

Intellectual 825 points

i will try change 760390014, but i use the same LDO, but the LDO damaged.

0 Ryan Tan over 3 years ago in reply to user6501051

TI__Expert 3356 points

Please check if the new transformer will damage your LDO. Again, if you have the waveform for LDO input and output, that will make it easier to analysis.

0 user6501051 over 3 years ago in reply to Ryan Tan

Intellectual 825 points

thanks

Simulation, hardware & system design tools

Simulation, hardware & system design tools forum

TIDA-010030: about the Isolated power supply