Patent ID: 6230001
Filing Date: 2001-05-08
Classification: H03D

Abstract:
An active double balanced mixer comprising:a transformer having a primary with a first end terminal connected to an RF input signal and a second end terminal to ground and a secondary with a center tap connected to ground;a first resistor having a first end connected to a first end terminal of the transformer secondary;a second resistor having a first end connected to a second end terminal of the transformer secondary;a first transistor with a first terminal connected to a second end of the first resistor and a second terminal connected to a local oscillator signal;a second transistor with a first terminal connected to the second end of the first resistor and a second terminal connected to a 180-degree phase shifted local oscillator signal;a third transistor with a first terminal connected to a second end of the second resistor and a second terminal connected to the 180-degree phase shifted local oscillator signal;a fourth transistor with a first terminal connected the second end of the second resistor and a second terminal connected to the local oscillator signal;a third resistor with a first end connected to a third terminal of the first transistor and the third transistor and an IF output, and a second end connected to a power source; anda fourth resistor with a first end connected to a collector of the second transistor and the fourth transistor and a 180-degree phase IF output, and a second end connected to the power source.