Re: Substituting a 74HCT74 for a 4013

From: John Fields (jfields_at_austininstruments.com)
Date: 03/27/05 

Date: Sat, 26 Mar 2005 19:25:39 -0600

On Sat, 26 Mar 2005 18:29:17 -0600, Chris W <1qazse4@cox.net> wrote:

>Can someone tell me how I could use a 74HCT74 in place of the 4013 in
>this circuit...
>http://www.uoguelph.ca/~antoon/gadgets/rc-sw.htm
>
>I tried adding a pull up resistor to both sets and the second reset.
>Then I ran the first Q output into one of the inverters on a 7404, with
>the capacitor to ground and then the output of the inverter into the
>first reset but it still doesn't seem to be working. Any ideas? I
>really don't know what I am doing here. Oh and I just need the high or
>low output, I don't need the TMOS FET.

--- ___ _____
The HC74 needs a logic low asserted on the SET and RESET inputs in
order to make them work, while the 4013 needs a logic high to do the
same thing. Therefore, if you want to substitute an HC74 for a 4013,
you'll need to invert the signals driving SET and RESET on the 4013. 

-- 
John Fields

Relevant Pages

  • Re: Simulating Inverted Registers
    ... I have a 32-bit register that I load a default value into during ... In actuality the "inverters" don't really exist. ... "standard" way of dealing with this in simulation? ... process(clk, reset) ...
    (comp.lang.vhdl)
  • Re: Substituting a 74HCT74 for a 4013
    ... >> The HC74 needs a logic low asserted on the SET and RESET inputs in ... >> you'll need to invert the signals driving SET and RESET on the 4013. ... You don't really need an inverter. ... on the first flipflop and tie the unused sets and reset to 5V instead of ...
    (sci.electronics.basics)
  • Re: Substituting a 74HCT74 for a 4013
    ... >>The HC74 needs a logic low asserted on the SET and RESET inputs in ... >>you'll need to invert the signals driving SET and RESET on the 4013. ... >there is obviously going to interferer with my capacitor charging. ... >Shouldn't the capacitor pull an input down to 0 volts or is this thing ...
    (sci.electronics.basics)