电子密码锁为三位密码，由输入部分，控制部分和输出部分组成。其中输入部分包括4×4矩阵键盘、弹跳消除电路、键盘扫描电路、键盘译码电路；控制部分包括按键存储电路、密码修改电路、比较电路；输出部分主要是七段译码显示器。当输入三位正确密码时，一个L1发光二极管亮，指示门打开；当输入密码错误时，另外一个发光二极管亮，此时可以通过开锁开关（复位开关）重新输入密码。若想实现密码更改，可重新按下上锁开关设置密码，即实现密码更改功能。-Electronic locks on the three passwords, the input, the control section and output components. Enter some of which include 4 × 4 matrix keyboard, bounce elimination circuit, the keyboard scanning circuit, the keyboard decoder circuit　control section includes key memory circuits, the password modify the circuit to compare the circuit　output part of the main seven-segment display decoder. When you enter the correct password three, a L1 LED light to indicate the door open　When you enter your password wrong, the other a light-emitting diode light, then you can unlock switch (reset switch) to re-enter the password. To achieve the password changes, press the lock switch can be re-set the password, that password change functionality to achieve.