CMOS Combination lock

Posted on Mar 10, 2013

his Electronic Lock circuit is not only simple but it is also very good. It can easily be configured to provide either momentary or continuous output. Key sequences of up to 9 digits are possible. You can pre-enter part of the combination and then have someone else enter the last few digits at a later time allowing for one-time access. This circuit has good debounce but there are some REALLY crappy switches out there so please look for types with spring or snap contacts. For better security or for a mad-scientist look you might use unlabelled pushbuttons arranged in some unusual shape.

CMOS Combination lock
Click here to download the full size of the above Circuit.

Leave Comment

characters left:

New Circuits



Popular Circuits

X-Rays with Receiving Tubes
Wireless Ir Security System
series robot circuit
Bus / Register Tutorial
LED Drivers/LCD Bias
How to Wire This Latching Relay
Simple Surround Sound Decoder
Electronic siren circuit
difference between half full bridge plasma speaker 2
network rs232
Ethernet remote device controller sensor circuit
Ultrasonic anemometer Ultrasonic wind sensor
Multiplication circuit in broadband video band used
As one of the thyristor type delay circuit
Five uses tri-state logic audio pen CD4066 555
Basic Connection circuit diagram INA326 327 signals and power