UCD90160: Max Current Under Fault Conditions

Jaime C

Part Number: UCD90160

Hi all,

My customer let smoke out of the UCD90160 sequencer due to a possible lack of limiting resistors at the input that are below 2.5V.

In order to prevent further damage to future boards, could you advise on what the maximum current that can flow into the chip under a fault condition in order to choose an appropriate resistor value?

Thanks in advance,

Jaime

over 7 years ago

0 Zhiyuan Hu over 7 years ago

TI__Genius 9845 points

Jaime,

For GPIO pins, max current is 4mA but suggest limit current under 1mA. MON pins are high impedance.

All pins have protection diodes from the pin to V33D, in order to clamp pin voltage at 3.3V. When V33D is not powered, input voltage on other pins will forward bias the protection diode and thus back drive the 3.3V rail. This current must be limited, or, V33D should be powered before other pins.

Regards,

Zhiyuan

0 Jaime C over 7 years ago in reply to Zhiyuan Hu

TI__Intellectual 990 points

Thanks for the quick response.

Was this information noted in the datasheet? If so, could you point to where I could reference it?

Jaime

0 Jaime C over 7 years ago in reply to Jaime C

TI__Intellectual 990 points

Zhiyuan, I would also like to ask if current into the MON pins under normal operating conditions is 100nA as listed in the datasheet as the input leakage current ? Am I understanding this correctly?

0 Zhiyuan Hu over 7 years ago in reply to Jaime C

TI__Genius 9845 points

Yes.

Power management

Power management forum

UCD90160: Max Current Under Fault Conditions