**Part Number:**TPS40210

Hi Sir,

My cusotmer use TPS40210 at their PoE boost application.They use excel tool to calculate the setting of components. But there're some mismatch between excel tool and equations at datasheet. For example:

1. Inductor selection: Their Vin max is 5.25V, max output current is 0.2A adn Vout is 51V. So if using equations 32 to 36 at datasheet page 27, the Induct(min) is 24.6uH, but if using excel tool, they'll get 22uH.

2. Rsense selection: If using equation 39 and 40 on datasheet, R(ISNS) might be 49.34m ohm and it'll cause system OCP. But if using the calcuation value on excel tool, it will be 12m ohm and system is stable.

What customer have to take care if they use equation value to build up their sysem in stad of using excel tool? And why there are different result between datasheet's equations and excel tool? Please help to clear it for my customer. Thanks.

Regards,

Gary Teng