Circuit 2
PARTS:
CIRCUIT #5
5
IC
1
X
LED
8
X
Circuit 2
In this circuit, we are going to use some of the lessons we
learned in circuit 12 to control a relay. A relay is basically
an electrically controlled mechanical switch. Inside that
harmless looking plastic box is an electromagnet that,
when it gets a jolt of energy, causes a switch to trip. In
this circuit, you’ll learn how to control a relay like a pro
– giving your RedBoard even more powerful abilities!
Relays
PARTS:
CIRCUIT #13
13
Transistor
P2N2222AG
1
X
Relay
1
X
1
X
Diode
1N4148
Wire
14
X
330Ω
Resistor
2
X
LED
2
X
When the relay is o, the COM (common)
pin will be connected to the NC (Normally
Closed) pin. When the relay is on, the COM
(common) pin will be connected to the NO
(Normally Open) pin.
IOREF
RESET
RESET
7-15V
SCL
SDA
AREF
GND
13
12
~11
~10
~9
8
7
~6
~5
4
~3
2
1
0
TX
RX
13
3.3V
5V
GND
GND
VIN
A0
A1
A2
A3
A4
A5
POWER
ANALOG IN
DIGITAL (PWM~)
ON
ISP
TX
RX
Resistor (330 ohm)
(Orange-Orange-Brown)
Resistor (330 ohm)
(Orange-Orange-Brown)
LEDs
(Light-Emitting Diodes)
Page 69