0
\$\begingroup\$

I'd like to build a very simple voltage comparator circuit with the following properties:

  • Vs = 5V
  • V- = Ground
  • Vout = 5V if V+ >= 200mV
  • Vout = 0V if V+ < 200mV

I'm using this comparator: NTE943M http://www.nteinc.com/specs/900to999/pdf/nte943.pdf

Any help is greatly appreciated.

\$\endgroup\$
  • \$\begingroup\$ Yes you can do that. Just apply a 200 mV reference voltage to the inverting input. Do you have a more specific question? \$\endgroup\$ – The Photon Sep 11 '14 at 0:34
  • \$\begingroup\$ My output doesn't go to 5V, do I need some pull up resistor or other feedback? \$\endgroup\$ – hagope Sep 11 '14 at 0:37
  • \$\begingroup\$ basically id like to detect a rising edge \$\endgroup\$ – hagope Sep 11 '14 at 0:41
  • 1
    \$\begingroup\$ That's a crap datasheet (I'm pretty sure NTE doesn't make their own parts, just repackages other vendors' parts). You'd be better off to get a part with a better datasheet. But yes, it does look like you need a pull-up. \$\endgroup\$ – The Photon Sep 11 '14 at 0:48
2
\$\begingroup\$

The NTE934M is a copy of the LM393. Its outputs are 'open collector' and can only pull down. You need a pullup resistor (the datasheet suggests 1.5K).

| improve this answer | |
\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.