STR-W6000S power IC
 

l am working on a refrigerator board which uses STR-W6000S power ic The resistor to pin 3 of the ic is burnt beyond recognition. l tried to find out from the manufacturers data sheet but all the application circuits there have no value marked on the resistors. can anyone give a typical value or how to figure out this value?

STR-W6000S power IC
 

wrote:

l am working on a refrigerator board which uses STR-W6000S power ic
The resistor to pin 3 of the ic is burnt beyond recognition.
l tried to find out from the manufacturers data sheet but all
the application circuits there have no value marked on the resistors.
can anyone give a typical value or how to figure out this value?



** The data sheet gives a typical value of 0.27 ohms @ 1 watt - in the table under fig 22. If it burns out, the IC is history.



...... Phil

STR-W6000S power IC
 

On Saturday, 1 April 2017 19:21:46 UTC, wrote:
l am working on a refrigerator board which uses STR-W6000S power ic The resistor to pin 3 of the ic is burnt beyond recognition. l tried to find out from the manufacturers data sheet but all the application circuits there have no value marked on the resistors. can anyone give a typical value or how to figure out this value?

Thanks l have changed the ic and try that value too

STR-W6000S power IC
 

The reference design for that chip shows a 0.27 ohm/1W resistor. Select a
low inductance type such as a carbon composition resistor here... definitely
not a wirewound type.

http://pdf1.alldatasheet.com/datashe...TR-W6000S.html

Cheers,
Dave M


wrote:
On Saturday, 1 April 2017 19:21:46 UTC, wrote:
l am working on a refrigerator board which uses STR-W6000S power ic
The resistor to pin 3 of the ic is burnt beyond recognition. l tried
to find out from the manufacturers data sheet but all the
application circuits there have no value marked on the resistors.
can anyone give a typical value or how to figure out this value?

Thanks l have changed the ic and try that value too

STR-W6000S power IC
 

On Sunday, April 2, 2017 at 3:30:43 PM UTC-4, Dave M wrote:
The reference design for that chip shows a 0.27 ohm/1W resistor. Select a
low inductance type such as a carbon composition resistor here... definitely
not a wirewound type.

http://pdf1.alldatasheet.com/datashe...TR-W6000S.html

Cheers,
Dave M


wrote:
On Saturday, 1 April 2017 19:21:46 UTC, wrote:
l am working on a refrigerator board which uses STR-W6000S power ic
The resistor to pin 3 of the ic is burnt beyond recognition. l tried
to find out from the manufacturers data sheet but all the
application circuits there have no value marked on the resistors.
can anyone give a typical value or how to figure out this value?

Thanks l have changed the ic and try that value too

You definitely should spec a low inductance type for the source resistor at these freq, but even certain carbon comps are supposedly trimmed in a spiral pattern making them inductive..

There are non inductive types available but they're tough to find. Still, I'd try any resistor before a wirewound in this app.

STR-W6000S power IC
 

Dave M wrote:


The reference design for that chip shows a 0.27 ohm/1W resistor. Select a
low inductance type such as a carbon composition resistor here... definitely
not a wirewound type.


** Good advice, but where do you get carbon composition resistors in that value? The IC will operate fine with readily available metal film types.

And beware, there are some wire wound types that look *exactly* like metal film ones.

I was fooled by this once and the PSU would not start up normally.


..... Phil