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LED seven segment counter

om

A "PNP sensor" traditionally means a three wire sensor (V+, OUT, and GND) whose output is the collector of a PNP transistor whose emitter is tied to V+. This means you need a load (typically a resistor) to GND in order for the circuit to complete, like this (View in fixed font or M$ Notepad):

V+ .------------o | .----o------. | | | | '----. | | | | | |< | | -| | | |\\ | | | | | | | | | | Out Vr | '-------o-----o | | | | PNP Sensor| .-. | | | | 1K '----o------' | | | '-' | GND | '-------------o----' created by Andy=B4s ASCII-Circuit v1.24.140803 Beta

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A couple of questions, if you would:

  • What's your power supply voltage? Is it regulated?
  • Is your counter a mechanical counter, an electronic counter, a CMOS or TTL counter IC, or what?
  • Is this an electrically noisy environment?
  • Specifically what is your PNP sensor (as in make and model), and what load is it driving? A resistor or what?

This would give you a start on a discussion about your problem, instead of just waiting for us to guess what you mean. You'd be amazed at how many people on s.e.b. will be willing to help, if you provide a good problem description.

Chris

Reply to
Chris
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I have a counter i want to increment with a normally open output wire from a pnp sensor. When i activate the sensor the counter counts at an incredible rate. Could anyone help me with this?

Reply to
Darlapphood

Sounds like you need a debouncing circuit. Can be as simple as a couple NAND gates in series. Also if the sensor doesn't offer both high and low (ie low and open) then you will need a pullup resistor either to VCC or ground to compenstate for open connection.

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Reply to
Impmon

fr=

segment

and what

the output directly into the input of the 4029 is this wrong? I'm a super beginner =(

Reply to
Darlapphood

Please learn how to write replies. Don't write within other people's quotes, it's almost impossible to find the text you write.

-- Sincerely, |

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Rikard Bosnjakovic | Code chef - will cook for food

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Reply to
Rikard Bosnjakovic

Is it regulated? not sure

Electrically noisy environment? no

Inductive proximity switch DC 10-30v model AE1-AP-1A

I just put the output directly into the input of the 4029 (CLK)is this wrong? I'm a super

Do i need to setup some sort of relay or i've heard people talk about a pull up. I want to understand but I dont.I need specific part numbers and names of components because im wicked new at this.

Could i trigger some sort of event with the sensor that increments the counter once?

Please any help is very much appreciated. Thanks.

Reply to
Darlapphood

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