High current sinking by PTH12000WAH

Alexandre Marcotte

Other Parts Discussed in Thread: PTH12000W, PTH08T230W

Hi,

I designed a PCB that uses a PTH12000WAH to regulate 12V input to 5V output voltage. When the unit is powered on, the PTH12000WAH module sinks permanently 150mA when a load is either connected or not. I used those capacitors : EEE-1CA101WP

I changed the module with another one and the problem is always there.

It is possible that my input capacitor would cause this problem? I checked my PCB circuit many time and no problem has been found.

Note: on the schematic, you can see 5V5, but it should be written 5V and the RSET resistor should be 280Ω

Thank you!

Alexandre Marcotte

Student at Sherbrooke University

over 12 years ago

0 Tom Guerin over 12 years ago

TI__Mastermind 38230 points

Panasonic : EEE-1CA101WP has a ripple current ranting RMS of 70MA . The minimum ripple current rating for the PTH12000W is 750mA rms.The ripple current rating information is published in the product specification under capacitor recommendation. The capacitor will fail in this application and possible have increased input current. The average input current with no load is about 100-125mA.

Tom

0 Alexandre Marcotte over 12 years ago in reply to Tom Guerin

Prodigy 50 points

Hi Tom,

I was thinking that a switching power supply like this module would have a very high efficiency. The PTH12000W is getting pretty hot when no current (or very low) is needed by my application.

All of the PTH products have the same behavior?

Thank you for your help

Alexandre

0 Tom Guerin over 12 years ago in reply to Alexandre Marcotte

TI__Mastermind 38230 points

Alexandre:

I suggest the PTH08T230W for this application. Average input current at 5V5 is about 75mA with 12Vin . The component temperature at no load is about 49°C.

Tom

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High current sinking by PTH12000WAH