Class B push-pull differential amplifiers of the single-end output

A differential amplifier comprising:

• an input differential pair constituted by differential pair transistors whose common emitter is current-biased by a negative voltage source through a constant current source;
• an active load which is formed by interconnecting through resistors input and output of a first and second current mirror circuit constituted by transistors having conductivity opposite to that of said differential pair whose emitters serve as positive voltage sources and in which a collector output of each of said input differential pair is connected to each of the outputs of said first and second current mirror circuits;
• and
• an output current amplifying stage comprising three emitter-grounded current amplifying stages including a first, a second, and a third current amplifying stages which are formed using transistors having the same conductivity as the transistors forming the active load and whose emitters serve as positive voltage sources, the first current amplifying stage including a capacity provided between the base and collector thereof and connected to one of current mirror outputs of said active load at the base thereof, the second and third current amplifying stages being connected to the other current mirror output of said active load at a common base, and each of collectors output, one of collector outputs thereof being connected to a negative voltage source through a resistor with a capacity provided between the base and collector, the other collector output being connected to the input of a third current mirror circuit formed using transistors having the same conductivity as said differential pair transistors whose emitters serve as negative voltage sources, wherein
• the output of said third current mirror circuit is connected to the output collector of said first current amplifying stage to provide a single-end output.