In the data sheet (lm393.pdf from the TI web site) on page 9 it says
The output consists of an open drain NPN (pull-down or low side) transistor. The output NPN will sink current
when the positive input voltage is higher than the negative input voltage and the offset voltage. The VOL is
resistive and will scale with the output current. See Figure 3 for VOL values with respect to the output current
Then on page 11 it says
1. When both IN- and IN+ are both within the common-mode range:
(a) If IN- is higher than IN+ and the offset voltage, the output is low and the output transistor is sinking
current
(b) If IN- is lower than IN+ and the offset voltage, the output is high impedance and the output transistor is
not conducting
These seem to contradict each other.
It looks like the second paragraph is right from the way my board works. Am I correct? Is there an error in the data sheet or am I understanding something wrong?
Thanks
Tim Woolaver
