|
Optical Interrupter Draws Microamps - This circuit is great for battery powered
systems that use slotted type optical interrupters. It draws only 10uA from a 3v
battery which should allow up to 5 years of operation from a lithium battery.
….(designed by David A. Johnson) |
|
Opto isolated 1-Wire bus - When building a 1-Wire MicroLAN, you can run into some
difficulties in the way of safety and realibilty. Reason is that the whole network has
a galvanic coupling…(added 07/07/07) |
|
OptoCoupled Gate Detects Motor Operation - 02/02/98 EDN-Design Ideas: (design idea
added 3/03) |
|
Optocoupler extends high side Current Sensorto 1 kV - 03/01/01 EDN-Design
Ideas:.....(design idea added 11/05) |
|
Optocoupler isolates Shift Registers - 01/20/00 EDN-Design Ideas:.....(design idea
added 05/03) |
|
Optocoupler simplifies Power line monitoring - 01/10/02 EDN-Design Ideas: The use
of a linear optocoupler and a capacitor-based power supply yields a simple, yet
precise power-line-monitoring system. The circuit in Figure 1 converts the 110V-ac
power-line voltage to an ac output voltage centered at 2.5V, covering 0 to 5V. The
circuit isolates the output signal from the power line.....(design idea added 1/05) |
|
Optocouplers are handy for Motor Drive - 06/13/02 EDN-Design Ideas: Figure 1a
shows a latching circuit based on an optocoupler, IC1. If the off switch remains
closed, pressing the on switch powers the LED in the optocoupler. Thus, the transistor
in IC1 turns on. You can now release the on switch, and the transistor remains on. You
must adapt the current-limiting resistor, R, to the power-supply voltage and
the.....(design idea added 1/05) |
|
Optoisolator Block Occupancy Detector - (electronic circuit added 7/03) |
|
Optoisolators compute watts & volt amperes - 02/21/08 EDN-Design Ideas: Relying on
the dynamic conductance of optoisolators' junctions, simple optoisolator bridges
compute the watts and volt-amperes of an ac load.....(design idea added 09/08) |
|
Phone Wire RJ 11 jacks & optocouplers Build a Bus - 12/24/04 EDN-Design Ideas:
Although cutting-edge technology reaps publicity, the real world often runs on modest
hardware that's just "good enough" for home automation, alarm systems, and
equipment-monitoring application.....(design idea added 1/05) |
|
RS232C Circuit has Galvanic Isolation - 02/04/99 EDN-Design Ideas: You can obtain
longer transmission distances with the RS-232C interface if you use galvanic isolation
between the two linked terminals. Galvanic isolation also eliminates problems arising
from disparate potentials between terminals. Using two MAX860/861 ICs.....(design idea
added 5/03) |
|
RS-232-to-RS-232 Port Powered Optical Isolator - Brochure with schematic in PDF
format / (added 7/02) |
|
Schematic of a Test Fixture for testing JFETs - (electronic circuit added
08/08/08) |
|
Signal-powered linear optocoupler provides isolated control signal - 07/23/09 EDN
An optoisolator provides isolation for a control voltage and supplies loop
forever.....(design idea added 08/09) |
|
Square Wave Driver Has Flexible Outputs - This circuit can produce an output
signal ranging from DC to 100KHz. It can source a voltage ranging from 1v to 30v. It
can sink a voltage ranging from zero volts to –30v. It can drive up to 200ma of
current and can even be switched to a floating tristate output. ….(designed by David
A. Johnson) |
|
Temperature Sensor uses I2c Isolator - 06/06/96 EDN-Design Ideas: You can couple
an LM75 digital output-temperature sensor through an isolated I2C (interintegrated
circuit)interface (see Reference)as shown in Figure 1. Electrically isolating the
sensor allows operation in situations prone to high common-mode voltages; it's also
useful in breaking ground loops. IC1 and IC2 comprise a bidirectional
isolator.....(design idea added 6/03) |
|
Time to Dust Indicator - I thought about this circuit when I heard that a lot
cleaning personal in hotels were either dusting rooms more often than necessary or not
enough. I have not yet built and tested this circuit completely but in concept it
should work. The circuit draws very low current from a +3v battery and could be housed
in a package similar to a small ashtray. The assembly might be placed in a suitable
out of the way area to collect dust. It would alert a maid when it was time to dust
the room. The circuit detects dust with an infrared LED that is pulsed so its light
shines onto a smooth flat plate. Any dust settling onto the surface is detected by a
phototransistor, mounted at a 90-degree angle from the LED. When the dust reaches a
particular level, sufficient light is reflected into the phototransistor to change the
logic state of the circuit to an alarm condition. The alarm output could be connected
to a beeper, a flashing LED or to one of the LED flashing circuits in this hobby
circuit section. ….(designed by David A. Johnson) |
|
Tube Line Driver/Preamp - Published in Glass Audio #2/1993 (circuit design
added 08/08/08) |
|
TV/Radio Antenna Cable Galvanic Isolator - (design circuit added 8/02) |
|
Vacuum Tube Opamp Circuit - Published In Glass Audio #3/1995 (circuit design
added 08/08/08) |
