topic Re: PCA9450 Absolute Maximum Ratings in Powertrain and Electrification Analog Drivers

PCA9450 Absolute Maximum Ratings

kouichinakahash — Mon, 07 Oct 2024 11:41:51 GMT

The LX5 pin MAX in PCA9450AA datasheet 7.1 Absolute Maximum Ratings states "INB45 + 0.5V", but this may be exceeded due to the voltage charged in the external capacitor, such as when the power is turned from ON to OFF. Is it correct to assume that this regulation applies only when the Input voltage is normal (VSYS=INB45=2.7 to 5.5V)?

Re: PCA9450 Absolute Maximum Ratings

gary598byers — Mon, 07 Oct 2024 12:15:07 GMT

Hello,
Yes, the “INB45 + 0.5V” regulation for the LX5 pin in the PCA9450AA datasheet applies under normal operating conditions (VSYS=INB45=2.7 to 5.5V). Exceeding this limit due to external capacitor voltage during power transitions could potentially damage the device12. Ensure proper design to avoid such scenarios.

Best Regards,
Gary Byers

Re: PCA9450 Absolute Maximum Ratings

kouichinakahash — Mon, 07 Oct 2024 23:11:05 GMT

Hello,

I am very sorry, but I made a mistake with the item number listed on the datasheet, so please let me check again.
The limit value of "LX4, LX5" Max = "INB45 + 0.5V" listed in Table 70 of the PCA9450 datasheet applies only under normal operating conditions (VSYS = INB45 = 2.7 to 5.5V), so is it correct to think that it is invalid when the input voltage transitions from ON to OFF?
This is because I believe that this is unavoidable, as residual voltage will remain on the output pins "LX4, LX5" due to the load capacitor even when the input voltage is turned OFF.

Best Regard.