• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 48 subscribers
  • Views 931 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM393: Contradiction in the LM393 data sheet.

Timothy Woolaver
Prodigy 110 points
Part Number: LM393

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

  • 0
    TI__Mastermind 49906 points

    Hello Timothy,

    We are aware of the contradiction. The corrected LM393 datasheet release was delayed due to other issues.

    The wording in section 8.2.2.1 is correct.

    The following is the revised text of Section 7.3:

    "The output consists of an open drain NPN (pull-down or low side) transistor. The output NPN will sink current
    when the negative input voltage is higher than the positive 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."

    A corrected datasheet should appear next week.