Parts List

the following parts list should serve as a general guideline for building a chronome. please make sure to read the comments and special instructions.  Thank you.

Sparkfun

Quantity Part Number Description Unit Price Total
1 DEV-09949 Arduino Mega $64.95 $64.95
4 COM-07835 Button Pad 4×4 – LED Compatible $9.95 $39.80
70 COM-08588 Diode Small Signal – 1N4148 $0.14 $9.80
1 COM-10017 LED – RGB Diffused Common Cathode (100 pack) $59.95 $59.95
4 COM-10136 TLC 5940 – PWM Driver $5.95 $23.80
4 PRT-07942 DIP Sockets Solder Tail – 28-Pin 0.3″ $1.50 $6.00
4 COM-08375 Capacitor Ceramic 0.1uF $0.25 $1.00
5 PRT-00116 Break Away Headers – Straight $1.50 $7.50
Total Does not include shipping $212.80

Digikey

Quantity Part Number Description Unit Price Total
2 ASC20H-ND CONN IDC SOCKET 20POS 15 GOLD $2.22 $4.44
2 ASC16H-ND CONN IDC SOCKET 16POS 15 GOLD $2.12 $4.24
2 A30992-ND CONN RECEPT 8POS 26AWG MTA100 $0.48 $0.96
1 493-1827-ND CAP ALUM 470UF 25V 20% RADIAL $0.53 $0.53
8 490-3847-ND CAP CER 470PF 50V 10% RADIAL $0.42 $3.36
1 770-101-R10KP-ND RES ARRAY 10K OHM 9 RES 10-SIP $0.58 $0.58
1 AE09G-5-ND CABLE 9 COND 5′ GRAY RIBBON $1.30 $1.30
1 AE16G-5-ND CABLE 16 COND 5′ GRAY RIBBON $2.07 $2.07
1 AE20G-5-ND CABLE 20 COND 5′ GRAY RIBBON $2.58 $2.58
3 S1KHCT-ND RES 1K OHM 1/2W 5% CF MINI * $0.11 $0.33
4 S6.2KQCT-ND RES 6.2K OHM 1/4W 5% CF MINI $0.08 $0.32
1 S5.1KQCT-ND RES 5.1K OHM 1/4W 5% CF MINI ** $0.08 $0.08
3 PN2907ABUFS-ND TRANSISTOR AMP PNP SS GP TO-92 $0.49 $1.47
Total Does not include shipping $22.26

* resistor value can be changed to affect the brightness of the Red, Green, and Blue leds. basically, you can change this to do manual dot correction. each resistor goes to a base pin of one of the transistors. changing the resistor value alters the gain on the transistor.

** resistor sets the overall brightness of the chronome. see the Iset in the TLC5940 datasheet for more info.