|
Oscillators: Astable
Circuits, Page 3
#'s - D
E - S
T - Z
Oscillator
Circuits -- Main Page
Last Updated on:
Tuesday, April 17, 2012 08:17 AM |
|
|
Circuits Designed by Dave Johnson, P.E. : |
-
Three Volt Low Battery Voltage Flasher
This circuit is designed to monitor two alkaline cells (3v) that form the battery
often used in portable electronic equipment. It use an inexpensive IC from
Panasonic that is connected to an efficient LED flashing circuit. When the
battery voltage drops below a certain point the circuit flashes the LED. In
the off state the circuit draws only 1uA, while in the active flashing state it
draws 20uA. Published in EDN, Jan 2, 1997
|
|
|
|
- Ultra Low
Current Oscillator February 17,
2009
Here is a challenge. Design an astable oscillator which draws only a few
nanoamps of current from a +3v supply. I gave this some thought and came up
with the circuit below. I used some pretty standard parts except for three
surface mounted 1000M resistors I had on hand. The oscillator frequency
measured a low 1Hz frequency and the average current was a very low 3 nanoamps.
If I had some higher resistors values handy, I think I could have gotten the current
down below one nanoamp.
|
- Ultra Low
Power Astable Multivibrator
Taking advantage of some new voltage comparators, this circuit can produce a nice
square wave signal while drawing only 1.6 microamps. With the inclusion of a
diode, the circuit can also produce short pulses instead of a square wave signal.
(added 12/04)
|
|
|
|
Links to electronic circuits, electronic schematics, designs for engineers,
hobbyists, students & inventors:
|
|
Three Volt Low Battery Voltage Flasher - This circuit is designed to
monitor two alkaline cells (3v) that form the battery often used in portable
electronic equipment. It use an inexpensive IC from
Panasonic....[Designed by David A. Johnson] |
|
|
|
Turn a set/reset latch into an astable/monostable multivibrator -
3-Sep-09 Issue of EDN Use latches with either active-high or
active-low inputs.... [Design Idea by Luca Bruno, ITIS Hensemberger Monza,
Lissone, Italy] |
|
Ultra Low Current Oscillator - Here is a challenge. Design
an astable oscillator which draws only a few nanoamps of current from a +3v
supply. I gave this some thought and came up with the circuit
below.....[Designed by David A. Johnson] |
|
Ultra Low Current Oscillator #4 - The circuit below was inspired
by a programmable unjunction transistor (PUJT) circuit sent to me by Karl
Isbrecht. In Karl’s circuit, the unijunction circuit made click sounds
in a speaker and consumed very little power. His circuit reminded me
that a PUJT circuit could be made using a couple common transistors wired in
a configuration like a SCR. In the circuit below, the output of the
two transistor pulse generator is connected to a CD4013 dual flip/flop.
One flip/flop is configured as a non-inverting buffer. The second is
wired as conventional divide by two counter. The result is a nice low
frequency square wave generator, which draws only 2ua from a 9v supply.
The circuit will also work with a DC supply voltage ranging from 3v to
15v.... [Designed by Karl Isbrecht] |
|
|
|
Ultra Low Power Astable Multivibrator - Taking advantage of some new voltage
comparators, this circuit can produce a nice square wave signal while drawing only 1.6
microamps. With the inclusion of a diode, the circuit can also produce short
pulses instead of a square wave signal. (added 12/04) …. [Designed by David A.
Johnson] |
|
Very Low Power Astable Multivibrator - This classic circuit draws only 200
nanoamps from a 1.5v supply.... [Designed by David A. Johnson] |
| |
|
|
|
|
Oscillators: Astable Circuits:
#'s - D
E - S
T - Z |
|
|
