3 V buffer (CB7142E)

This 3 V rail to rail buffer was found in a National Semiconductor documentation. The gain is unit.

Touch gain control (CB22143E)
This circuit is from an English book from the 1980s. Transistors can be general-purpose types of...
Variable Source 0 to 12 V x 1 A (CB12208E)
This circuit from the 80's can be easily implemented but needs some changes to avoid problems with...
Current to Voltage Converter (CB15726E)
The presented circuit provides an output voltage proportional to the input current, according to...