42 September 2013
■ FIGURE 2. Cut traces and add ground wire as shown.
Qty Description Part Number Source
Semiconductors
3 1N4004 rectifier 1N4004GOS-ND Digi-Key
1 L78L33 3.3V voltage regulator 497-7288-ND Digi-Key
1 2N2222 NPN transistor P2N2222AGOS-ND Digi-Key
1 74C922 keypad decoder IC 74C922 eBay
1 MSP340G2452 processor IC MSP430G2452IN20 Digi-Key
Resistors
1 22 ohm 1/4 watt resistor
1 470 ohm 1/4 watt resistor
Capacitors
1 0.01 µF capacitor
1 0.1 µF capacitor
1 1 µF / 16V electrolytic capacitor
1 47 µF / 16V electrolytic capacitor
1 1 µF / 100V non-polar capacitor (see text)
1 0.047 µF / 5.5V memory backup capacitor (see text)
Other
1 Piezo buzzer (or similar) PT-1245P-PQ Digi-Key
1 Datavision 10275 keypad G17927 Electronic Goldmine
1 Relay, SPDT 6 VDC coil (see text for contact ratings)
MSP-EXP430G2 development kit MSP-EXP430G2 Digi-Key
Magnetic reed security sensors, N/O contacts
Alarm siren (see text)
Cat-five cable
Perfboard 2" x 3"
6 VDC 500-1,000 mA wall-wart transformer
AC wall socket and plate (if using AC siren)
PARTS LIST
www.digikey.com
www.goldmine-elec-products.com
