TIOL111: Power consumption @ TIOL111 in IO-Link mode

Hi Marion,

Those calculations are a good reference for computing power dissipation in the device. The dominant contributors tend to be the power dissipation in the output switch and in the LDO (if applicable), and in both cases this is determined by the product of the output current and the voltage drop across those elements.

The reason that a higher current is used in the example is to account for some tolerance in the overcurrent detection. In this case the limit was set to 200 mA, but currents as high as 250 mA could occur before being recognized as an overcurrent (in which case the driver would be shut off).

When you say the customer is feeding their device through the output voltage, do you mean that the application is powered by the CQ output of TIOL111? This would be OK as long as the current consumption did not exceed the limit of our device and the power dissipation in TIOL111 is not so high as to cause excessive heating.

Max

Marion,

It is generally enough current to power simple analog circuitry (sensor elements, etc.) or a simple MCU. The maximum recommended output current from the LDO is 20 mA, and while this is achievable in many cases you should keep in mind that in practice it is limited by thermal concerns. This means that it depends on the power dissipation in the output switch (proportional to output current) as well as the operating temperature of the end application. (The power dissipation of the LDO itself will also vary with the L+ line supply voltage.)

Max