Electronic Parts List

Here are lists of parts and what they do.

Transistors

BC327
PNP 800mA

Transistor Arrays

In the arrays below, the mentioned capability is the absolute maximum for ONE pin, for a short time. Continous operation is usually around 100mA when all pins are ON.
UDN2983A
8 channel source driver. 500mA.
ULN2803A
8 channel sink driver. 500mA.
TPIC6B595
8 channel sink driver with serial interface. 500mA.
SN75468
7 channel sink driver. 500mA.

LED Drivers

Common cathode means that the current flows from pixel pins to digit pins. You drive the pixel pin with a PNP and the digit enable pin with an NPN.
MAX7219
Serial interface 8 digit driver for common cathode displays.

This chip can sink 500mA from each segment and provide up to 100mA to each pixel.

ICM7228CIPI
8 digit driver. A and C drive common anode, B and D drive common cathode. A and B are serial interface whereas C and D are parallel interface, like memory.

Timers

41T56
I2C, external XTAL, 56 byte RAM, battery backup. Some versions have SNAPHAT battery&XTAL pack for which error= 35 ppm, calibrated= 2ppm.
PCF8583
I2C, extern XTAL, 240 byte RAM, no battery.
DS3231
I2C, internal temperature compensated XTAL, battery backup. Very accurate. 2ppm error. Temperature sensor is also accessible thru I2C.

Logic Components

Digital to Analog Converters

Power Supply

USB Devices