High gain differential amplifier with positive feedback

In combination:

• first, second, third, fourth, fifth and sixth multiterminal semiconductor devices having respective conduction path terminals and a control terminal,
• the conduction paths of the first and second of said multiterminal devices connected in a first series circuit;
• the conduction paths of the first and the fifth of said multiterminal devices connected in a second series circuit;
• the conduction paths of the third and fourth of said multiterminal devices connected in a third series circuit;
• the conduction paths of the third and the sixth of said multiterminal devices connected in a fourth series circuit, said first and third series circuits connected together to form a first electrical junction with a source of relatively positive reference potential;
• the first output terminal connected to both the control terminal of said first device, to the first series circuit formed by the conduction paths of said first and second devices, and to the control terminal of said sixth device;
• a second output terminal connected to both the control terminal of said third device, the third series circuit formed by the conduction paths of said third and fourth and sixth devices, and to the control terminal of said fifth device;
• first and second input terminals respectively connected to the control terminals of said second and said fourth devices;
• said fifth multiterminal semiconductor device having a conduction path in parallel with said second semiconductor device,
• said sixth multiterminal semiconductor device having a conductor path in parallel with said fourth semiconductor device,
• a seventh multiterminal semiconductor device having conduction path terminals and a control terminal;
• said seventh multiterminal semiconductor device connected between a source of relatively negative reference potential and a second electrical junction formed by the connection together of said first, second, third,and fourth series circuits, and
• positive feedback means connected between said first output terminal and the control terminal of said seventh multiterminal device to control the conductivity of said seventh device.