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7486 IC problem

Ranveer

Nov 15, 2023
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17000658928797370024600071200582.jpg

What is wrong with this circuit it is xor ic which is not working even after checking multiple times as you can see 1 input is on but still motor is not on I have checked breadboard battery,motor and idk where problem is. Can you please help me figuring out problem.
 

danadak

Feb 19, 2021
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Are you trying to drive motor directly with 7486 output ? You cannot do
that, it does not have enough power / current capability to do that. Plus
you may have ruined the 7486 with the inductive load transients that a
motor produces.

Regards, Dana.
 

davenn

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Sep 5, 2009
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^^ what Dana said ^^

@Ranveer so tell us exactly what you are trying to achieve ?

cheers
Dave
 

bertus

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Nov 8, 2019
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Hello,

Also The 7486 needs a powersupply voltage of 5 Volts.
Your 9 Volts battery will likely fry the 7486.

Power_supply_voltages_for TTL_logic.png

Bertus
 

Ranveer

Nov 15, 2023
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Hi Bertus
If I use 5v power supply can I ignore use of resistor?
 

Bluejets

Oct 5, 2014
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If I use 5v power supply can I ignore use of resistor?
I think I know where you are going with this but it won't work that way.
The 74xx ic has an operating voltage of 5v as already shown and the gate of the ic is signal level only.
Not designed to run motors etc. directly.
A logic level mosfet buffer or similar might get the motor running but not on a smoke alarm battery.
 

Ranveer

Nov 15, 2023
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I think I know where you are going with this but it won't work that way.
The 74xx ic has an operating voltage of 5v as already shown and the gate of the ic is signal level only.
Not designed to run motors etc. directly.
A logic level mosfet buffer or similar might get the motor running but not on a smoke alarm battery.
I was testing IC with motors so If I connect 2 XOR ic out with input of OR IC without resistor (this is all for example) and connect output of resistor than to 5v led than the circuit is ok to go?
 

kellys_eye

Jun 25, 2010
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You can directly drive an LED using the logic level output of that gate but not a motor.

The device you showed in your first post is probably destroyed now since you used a 9V battery with it.
 

Ranveer

Nov 15, 2023
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You can directly drive an LED using the logic level output of that gate but not a motor.

The device you showed in your first post is probably destroyed now since you used a 9V battery with it.
Ok thanks for your assistance I was worried for using many resistor I would probably use 3v or 5v for IC.
 

bertus

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Hello,

Wich version of the 7486 is used?
In the table I posted you can find the working voltages.

Bertus
 

Harald Kapp

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I would probably use 3v or 5v for IC.
Not 3 V or 5 V. Look in the datasheet of the specific device (ic) you use and set the operating voltage accordingly.
I was testing IC with motors
As you've been told more than once by now: you can't drive a motor from a logic ic. You will need a driver which is able to deliver enough power. You could use a dedicated driver ic or a simple transistor, see e.g. our resource.
 

HellasTechn

Apr 14, 2013
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As mentioned above, the 74 serries IC's can only sink or source a few mA of current. Also 9V is too much. It might withstand a few "shots" of it but definitely not continuous supply.

if you supply it with 5V then you can use an npn transistor like the BC337 connected to the output to run the motor. Like the picture below.bc337.jpg
 
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