18 Pin IC Base Socket
IC Bases or Sockets are commonly used while soldering ICs to PCB. These are generally meant for avoiding the damages of IC during soldering and for easy replacement of ICs. Overheating of ICs may damage it which are generally costly components in a PCB. The usage of IC Base / Socket is inexpensive when compared to the time / effort required to replace an IC. Replacing an IC without IC base may also damage the prototype board. These IC sockets / bases are commonly made using thermoplastics and tin-plated alloy contacts. One end of these sockets are normally notched for identifying the direction of IC placement.
HT12E HT12D Encoder Decoder Pair
HT12E and HT12D are Encoder Decoder ICs manufactured by Holtek for Remote Control Applications. These ICs can be used with ASK RF Transmitter and Receiver modules. By using the paired HT12E encoder and HT12D decoder we can transmit 12 bits of parallel data serially. HT12D simply converts serial data to its input (may be received through RF receiver) to 12 bit parallel data. These 12 bit parallel data is divided in to 8 address bits and 4 data bits. Using 8 address bits we can provide 8 bit security code for 4 bit data and can be used to address multiple receivers by using the same transmitter.
ULN2803A Driver IC
ULN2803A is a one of the most commonly used High Current, High Voltage Darlington Transistor Array IC. It contains 8 NPN darlington pairs with common cathode clamp diodes for each outputs for switching inductive loads. The current rating of each darlington pair is 500mA and you may connect two or more darlington pairs in parallel to increase current capability. This IC is commonly used in applications such as Relay Driving, Hammer Driving, Lamp Driving, LED and Gas Discharge Display Driving etc.