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  1. E

    Can two N-Channel MOSFETs be connected in series to perform a "AND" function?

    Hello, I'm designing a circuit to ring a bell using a code set by the user. When powered the circuit steps through the code which is set via DIP switches to decide where a "ding" or a space should be within the code. Each "on" position within the code actuates a modified car relay which hits...
  2. Slickit

    Circuit for a up/down fade led with solid on option

    Hello. Simple one here for yall im sure but I am looking to make a little circuit for a custom power button for a computer that I am building that will up/down slow fade while off and then stay solid when the PC is powered on. Standard ATX power voltages / signals available and I think I will...
  3. S


  4. N

    555 with 74HC595 - no microcontroller

    hi everyone as a way of intro: I am new to this site and a relatively new electronics hobbyist. A quick summary of my circuit: I built a simple circuit with a 74HC595 w/ 8 output LEDs. I am looking to hook up the QH' back to the shift register's input pin. But, have not been able to get it...

    For a better sine wave

    Hello sir, This post might be a silly one, but my stupid brain does not find it well. I am looking for a signal generator circuit to fed different frequencies in other circuit. I have found one, take a look But, the person who posted this did wrong on inverting and non inverting sign...
  6. sr13579

    How to stop 555 IC from heating up?

    I was trying to make a LED flasher with 555 IC. Then I thought how about I set a transformer with the output-ground pins. And I also reduced the resistance between 7 and 6 pin. And I am getting a 31V AC output from my transformer output panel. Looks like it is possible to make an inverter with...
  7. D

    Simple 555 timer with delay after trigger release

    Hello. I am new to this chat, so I hope this is the right forum to post to. I have the idea to use a 555 to build a small triggered timer with an 'after release' delay. I have been google-ing but can not find the right schematic/design that looks to work for me, so I will try this forum :)...
  8. hackware

    558 timer for triple timing use...

    I'm just starting back designing with the 555 again, after a few years away from silicon valley... I need 3 (4?) timing functions, so a 558 seems like a good fit, if they can live with the reduced pins available to each timer. Functions needed: 1) variable speed oscillator 2) variable pulse...
  9. giovannithex

    IC555 - control pin

    Hello everyone. I'm wondering if (how) could i make it possible; I have simple circuit from two parts: one stands as PWM oscilator (555 timer) and that timer drives the transistor (npn, let us forget about efficiency for now) On the CE line of transistor i have connected a DC motor of which...
  10. V

    [Help] 555 IC Keeps Blowing Up

    Hi, I'm new to circuits and electronics stuff, so kindly help me to solve the issue. I'm trying to add led DRL to my car, everything is working well if I power my circuit with 9V battery, but if I connect it to car battery after 3-5 seconds it getting blown. I have no idea why it's happening...
  11. DannyDilla

    74HC164 + ULN2803 LED CHASER

    So a buddy of mine (Hi Bernard!) on another forum suggested I use a shift register for an idea I had. A little background--I'm pretty fresh out of college and I work with high voltages all day; mainly analog power, PCB Design, soldering, Hi-Pot and UL Certification. Digital Electronics is...
  12. G

    Lm3914 and a couple of 4014s

    It's not practical I know, but I thought it would be fun. A 200 LED oscilloscope as a good soldering project for low speed, simple projects etc, ie: 555 projects. Easy I thought, use the LM3914 to drive the ten vertical 10 LEDS while the two 4017s to handle the twenty horizontal LEDS in a 10x20...
  13. N

    555 Beginner problem

    Hi I have this assignment, and I have absolutely no idea what I’m doing. I need to design a circuit that produces the output as attached. T1=1ms Duty Cycle1 = 0.75 Duty Cycle2=0.75 T2 can be calculated from T1 tpw3 can be calculated from T2 I have to use monostable and astable...
  14. J

    555-4026b-7segment Counter Circuit.

    So. I have started a project on creating circuit that would be able to count money that I could use. The circuit would be able to count from 0-99 A circuit very much similiar to it can be seen here: http://www.circuitsgallery.com/2013/12/4026-digital-counter-circuit.html 1) Onthis link you can...
  15. J

    555 input desense

    I have a small project using a 555 timer in a monostable configuration However, I need an idea on how to block or desense the input signal for a second or so after the timer returns to baseline state My output (a solenoid) generates a transient upon closing that immediately retriggers the input...
  16. J

    Need Help on semi automatic water level controller using 555 in bistable mode

    I have build an semi automatic water level controller using 555 in bi stable mode i.e. it will not turn ON automatically (one should have to press a button to start) but will turn OFF automatically when water level is high.So I have directly connect the VCC to PIN 2 through a push to OFF...

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