Categories
 Audio
Amplifiers, Audio Filters, Beeper & Buzzer, Equalizers, Intercom Circuits, Microphone Circuits, Mixers, Musical Circuits, Preamplifiers, Stereo Circuits, Tone-Balance, Ultrasonic Circuits, Vacuum Tubes, ...
|
|
Automations
|
|
Automotive
|
|
Computer
|
|
Converters
|
|
Digital
|
|
Inside Circuits |
|
Light-Laser-LED
|
|
Meter/Counter
|
|
Microcontrollers
|
Oscillators
Astable, Audio, Colpitts, Crystal, Hartley, Monostable Circuits, Pierce, RF, Sine wave, Square wave, Volt controlled, Wein Bridge, ...
|
Other Circuits
Buffer Circuits, Demodulators, Doorbell Circuits, Game Circuits, H-Bridge Circuits, Keypad Circuits, Model Circuits, Mosfet Circuits, Radar Circuits, Sequencer, Switch Circuits, Triac Circuits, ...
|
|
Power Supplies
|
RF
AM Circuits, Amplifiers, Antennas, FM Circuits, FM Transmitters, GPS Circuits, PLL Circuits, Receivers, Transceiver Circuits, Transmitters, UHF Circuits, VHF Circuits, ...
|
|
Security
|
Sensors/Detectors
Air-Gas, Hall Effect, Human, Light, Liquid, Magnetic circuits, Medical, Metal Detector circuits, Optical, RF & Radiation, Various Circuits, Voltage, ...
|
|
Software
|
|
Telephone
|
|
Video
|
|
9v Battery Voltage Monitor
This circuit turns on a LED whenever the voltage of a standard 9v battery connected to the circuit drops below 7.2 volts. It uses a LTC1440 comparator, which also contains a 1.18v reference diode. In standby mode, the circuit draws only 4uA.
|
|
