FREE
circuits!
Lock circuit diagrams
August 3, 2010
This is a Universal version of the Four-Digit Alarm Control Keypad. I have modified the design to free up the relay contacts. This allows the circuit to operate as a general-purpose switch. I've used a... [more]
August 3, 2010
This is a simplified version of the 4-Digit Keypad Controlled Switch. I have modified the design to reduce the complexity of the circuit - and the number of components required. As a result - the... [more]
August 3, 2010
This circuit is designed to operate an electrical door-release mechanism - but it will have other applications. When you enter the four-digit code of your choice - the relay will energize for a preset time... [more]
August 3, 2010
It is a relatively simple circuit of electronic lock of safety with code of 7 digits. It should is given attention in the time that will be stepped the keys, that shape code and it... [more]
August 3, 2010
A different circuit of electronic lock very simple, one and does not need a lot of materials in order to it is manufactured. [more]
August 3, 2010
The digital lock shown below uses 4 common logic ICs to allow controlling a relay by entering a 4 digit number on a keypad. The first 4 outputs from the CD4017 decade counter (pins 3,2,4,7)... [more]
June 22, 2010
This electronic lock can be used with any type of iButtons you may already have, since the only thing needed is the internal serial number, that's different for every iButton. [more]
June 22, 2010
This circuit is an Electronic Locker. It is controlled by a switches combination (by a code). There is a switch matrix on the door of the locker. [more]
April 11, 2010
This is a universal four-digit keypad-operated switch - with a difference. Instead of entering the security code one number at a time - the four keypad buttons must be pressed simultaneously. Split the code between... [more]
This category