We will be supplying the device with 3,3V. The VOH is the critical parameter and we can only “afford” to let the output voltage drop 0,15V from the supply, so with a nominal 3,3V supply, we need VOHmin >3,15 @IOH = 0,7mA
Reading the datasheet, I find the following information :
It seems that @ 0,1mA, we have a “risk” of loosing 0,2V, and for 12mA it is 0,6V – how “conservative” are these figures ?
Another curve is found as well :
Looking at this curve, it seems that the output impedance around 3,3V and 1mA is 0,5V/18mA = 28ohms and VOH @IOH =-1mA is only a fraction below the supply voltage of 3V.
Can we safely use the curve above for determining the output “ON” resistance for the device ?
Do we risk loosing 0,2V@0,1mA as stated above or is this related to supplying the device with 1,65V only ?
Should the part of the curve exceeding VOH = 3V be interpreted as the device is being driven from the outside as shown on figure 8 in the datasheet (although not recommended)?