pattern) are stored in the PIC’s
internal EEPROM, and are
therefore not lost on reset or
power failure.
General Notes
Building this project is
probably at an advanced skill level,
mostly due to the number of
surface-mount parts. Even if you
don’t intend to build this clock,
you may enjoy reading the
September 2016 33
PART QTY VALUE DEVICE VENDOR
C1 1 1000 μF/35V Capacitor, polarized, 16 x 15 mm Mouser (647-URS1V102MHD )
C2 1 220 μF/50V Capacitor, polarized, 10 x 16 mm Mouser (667-EEU-FM1H221)
C3 1 10 μF tan/16V Capacitor, polarized, tantalum Mouser (581-TAP106K016SCS)
C4-C9 6 0.1 μF Capacitor, ceramic, through hole Mouser (75-1C10Z5U104M050B)
C10-C15 6 0.1 μF Capacitor, ceramic, 0805 SMD Mouser (581-08055C104K)
C16 + C17 2 12 pF Capacitor, ceramic, 0805 SMD Mouser (581-08055A120J )
C18 + C19 2 20 pF Capacitor, ceramic, 0805 SMD Mouser (80-C0805C200J5G)
D1 1 1N5819 Schotty diode, high speed Mouser (512-1N5819 )
D2 1 1N4001 Diode, rectifier Mouser (512-1N4001)
D3 + 4 2 1N4148 Diode, switching Mouser (512-1N4148)
D5 1 3N248 Diode bridge 1.5A Mouser (625-3N248-E4)
F1 1 1A Fuse, 10x3.8 mm Mouser (576-07771.25MRET1P) *
IC1 1 PIC16F876A-I/SO Eight-bit Microchip PIC (SO28W) Mouser (579-PIC16F876A-I/SO) *
IC2 1 CD4017BE Decade counter (DIL16) Mouser (595-CD4017BE)
IC3 1 LM2575T- 5 Switch mode regulator 5V (TO220-52) Mouser (863-LM2575T-5G)
IC4 1 SN74HC164N Eight-bit shift register (DIL14) Mouser (595-SN74HC164N)
IC5-10 6 CD4511BPW BCD to seven-segment driver/latch (SMD) Mouser (595-CD4511BPW)
IC11 1 ULN2803A Darlington transistor array (DIL18) Mouser (511-ULN2803A)
JP1 1 POWER_JACK Power jack, 7x2.1 mm Your favorite/various
JP2 1 Two-pin Straight 0.1" spacing with jumper block Your favorite/various
JP3 1 Five-pin Angled 0.1" spacing Your favorite/various
L1 1 330UH SMD power inductor Mouser (851-CDRH127NP-331MC )
LED1-60 60 UltraBrite LED LED 5 mm Your favorite/various
NU1-6 6 IV- 9 IV-9-Numitron eBay
R1-R8 8 1k6 Carbon resistor, 1/4W, axial lead, 5% Your favorite/various
R9-R13 5 10K Carbon resistor, 1/4W, axial lead, 5% Your favorite/various
R14 + R15 2 0R Use jumper wire Your favorite/various
R16-R18 3 1K Carbon resistor, 1/4W, axial lead, 5% Your favorite/various
R19 + R20 2 15K Carbon resistor, 1/4W, axial lead, 5% Your favorite/various
R21-R28 8 100 ohm Carbon resistor, 1/4W, axial lead, 5% Your favorite/various
S1-S3 3 Switch Long tactile button, 90 degree Mouser (506-FSMRA4JH04 )
X1 1 4 MHz Crystal, low profile Mouser (520-040-20-4X-DU)
X2 1 32 kHz Watch crystal Mouser (732-C002RX32.76K-APB) *
Circuit 1 N/A Favorite boardhouse
board
Wall wart 1 12V or 15V, 1.5A, (Connector to fit JP1) Your favorite/various
Spacer 4 M3x20 mm F-F Your favorite/various
Spacer 4 M3x15 mm M-F Your favorite/various
Screw 8 M3x10 mm Your favorite/various
Panel 2 8" x 8" x 1/4" acrylic Local plastics shop
Parts denoted with are specifically mentioned in the text. Please read before ordering.
PARTS
LIST
Soldering SMD Components
Small components are best soldered with small tools. That means a very fine
soldering tip, fine point tweezers, and very thin solder. The SMD components in
this project are not very difficult to solder, however, I'll describe the methods I use.
Caps, resistors, etc., come in many sizes; 0805 (used in this project) and larger
can easily be soldered as follows: Start with placing a small drop of solder on ONE
pad. With the tweezers, place the part on the pad, heat the drop, and push the part
in place (refer to Figure 10b in the text). If the part is not located properly, reheat
the one side and correct. Once properly placed, solder the other side.
A similar method is used for the ICs. Place solder on ONE pad, and place the
part. If not located correctly, reheat and reposition. Do NOT push to bend the leg
even a little bit. The legs will break easily, and the stress will add to future failure
chances (Figure 13a). Please see the construction manual at the article link for
more in-depth information.