DiscoverCircuits.com, has 28,000+ electronic
circuits, cross-referenced
into 500+ categories. We have searched the web to help you
find quick design ideas.
We make every effort to link to material posted by the designer.
Please let us if you would like us to link to your design.
Timers and Counters Circuits,
Page 2a Timers & Counters:
#-ANext
B-EPrevious B-EF-LM-S T-Z Last Updated on:
Friday, March 12, 2010 12:07 PM
Circuits Designed by Dave Johnson, P.E. :
CIRCUIT
FORMS DIVIDE BY 1.5 COUNTER
Two inexpensive ICs divide a TTL clock signal by 1.5. By following the circuit with
another flip/flop, you could also generate a divide by three function.
DARKROOM
CAMERA SHUTTER TIMER
This circuit was designed to control a film exposure shutter for a darkroom. It has
8 time steps ranging from 0.35 seconds to 4 seconds. It is activated by a foot
switch and draws power from an external 12 volt DC supply.
Links to electronic circuits,
electronic schematics, designs for engineers, hobbyists, students & inventors:
Delay line has Wide duty cycle range: 06/27/02 EDN Design Ideas /
(added 1/05) Today's digital delay lines can process pulses no shorter than
their delay times, and that restriction confines the devices to applications in
which the duty cycle remains near 50%. A limited range of available delays (2 to
100 nsec per tap) further limits their use. Longer delay is available with
one-shot multivibrators of standard digital-logic families, but those devices do
not retain duty-c......
Deoderizer Fan Pushbutton Timer : For use in a bathroom or car. I've
seen similar circuits used in plastic pot-pourri containers. (added 2/05)
Design Low duty cycle timer circuits: 08/22/02 EDN Design Ideas /
(added 1/05) Designing astable circuits using the industry-standard 555
timer is a straightforward process when duty cycles are 50% or greater. However,
you must overcome the many pitfalls of low-duty-cycle circuits to arrive at a
desired result. Using only ideal components eases the design, but the components
themselves are hard to obtain....
Digital Clock with Timer and Solar Panel Regulator: This is a
combination digital clock timer and solar panel charge controller used to maintain
a deep cycle battery from a solar panel. The timer output is used to control a 12
volt load for a 32.... (added 05/07)
Digital Timer Light Switch : Typical circuit representative of those
used in most light switch type digital timers. The timer module is normally a PIC
or custom chip, and it syncs to the AC line so that a trigger pulse can be
supplied at the right moment. (added 2/05)
Extend the timing capabilities of a PC: 01/10/02 EDN Design Ideas
/ (added 1/05) Even when you use the internal timing registers and
under DOS, a PC cannot easily measure time intervals with better time resolution
than a millisecond. Measuring long intervals with even this precision is a waste
of many CPU cycles. A microcontroller is well-suited for this task; you can easily
integrate a PIC with a PC to extend the timing precision into the microsecond
range for perio... ...
