got a 4017 comparator and LED 7 segs

hey all , i have a comparator (quad) 14 pin. can a get a brief tuitorial of them and also i recieved my 7 seg LED's for my clock (i know how the decade counter works) but the LED's have a voltage rating of 2-5 volts , now does that mean my supply (9V) battery cant be used because if i measure volts under the load of the 555 and counter the volts is only 2-3 V
just wanna be sure... in electrical i alway have to use a transformer or series loads to reduce voltage, in electronics is it correct to say it can be done by resisting current to 0V (still workin on my terminology) thanks , jim

LED's have a voltage rating of 2-5 volts , now does that mean my supply (9V) battery

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Put resistors in series with the LEDs to limit the current. Use the LED datasheet and Ohms Law to figure out the resistor values. ie: If the recommended LED current is 20ma (0.02A) and the LED voltage is 2V then 9-2=7V so; 7V / 0.02A = 350hm: so use the next highest standard value of 390hm:

A CD4017 is not a comparator. It is a counter/decoder with 10 outputs that sequence one after the other. It is not designed to drive a 7-segment display.

You can use a CD 4026 to drive your segments instead of 4017.

A CD4017 is not a comparator.

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I think the OP just forgot to use a comma:
got a 4017, comparator and LED 7 segs.
Plus a 4017 has 16pins so I think his 14pin comparator is a LM339 or something similar.

For a really good tutorial on comparators, see **broken link removed**

yea i had the 4017 listed on the subject i meant the comparator , sorry and thanks for your help.