| Part |
Qty |
Value |
Function |
IC1 |
1 |
ATmega88 |
main microcontroller |
IC2 |
1 |
LM7805 |
voltage regulator (+5V) |
C1,2 |
1 |
22 uF |
capacitors for LM7805 |
C3 |
4 |
10 nF |
key debouncing |
C4 |
5 |
100 nF |
decoupling capacitors |
D1,2 |
1 |
1N4004 |
diodes for power supply system |
R1 |
1 |
4.7 kΩ |
current limiting resistor for PD0 line |
R2 |
1 |
10 kΩ |
pull-down for PD0 line |
R3 |
4 |
150 Ω |
used for input |
R4 |
4 |
10 kΩ |
used for input |
R5 |
4 |
4.7 kΩ |
used for output |
R6 |
4 |
560 Ω |
used for output |
R7 |
1 |
10 kΩ |
/RESET line pull-up |
T1 |
4 |
BC457 |
npn transistor for LEDs |
X1 |
1 |
32.768 kHz |
RTC oscillator |
Bat |
2 |
AAA |
batteries for auxiliary power supply |
LED |
1 |
LED stripe |
light source |
H1 |
3 |
6-pin |
6-pin headers for interconnection |
H2 |
1 |
socket |
power supply socket |
H3 |
3 |
14-pin |
nest for the microcontroller |
H4 |
1 |
AAA |
battery holder |
PB |
4 |
|
push-buttons for input |
SW |
1 |
|
power switch for restarting |