The CD4015 is a Dual 4-bit Shift Register. It has a wide operating voltage upto 18V, hence can be used in high voltage applications. The IC is commonly used as I/O expander along with microcontroller to control multiple outputs like LED, LCD display etc..
The CD4012 is a CMOS technology based, 4-input NAND gate Dual package, i.e. the IC has two NAND gates which can operate independently and each gate can take in four Inputs. It is commonly used in buffer circuits, logic inverter circuits etc.
The CD4008 is a high speed, high voltage 4-bit full Adder IC with carry out feature. The IC has four independent stages of full adder circuits in a single package. It is commonly used in applications where arithmetic operations are involved.
Silicon Labs introduced a family of isolated analog amplifiers, voltage sensors and delta-sigma modulator (DSM) devices designed to provide accurate current and voltage measurement with very low drift across temperature.