Typical Applications

The design experience described here is a low IF double balanced mixer with a large dynamic range intended for automotive radar receivers. The unique layout keeps maximum isolation between RF and LO path. This experience is on Jazz SiGe120 (SBC18) Bi-CMOS process. The mixer linearity is designed for RF signal with a dynamic range of 9-10 dB. The noise figure of the mixer is secondary to linearity requirement. The NF related to 1/f noise is 15 dB @ 1 KHz and 10 dB @ 100 KHz. This noise performance across a large rf input signal dynamic range makes it a unique mixer in receiver front-end. The double balanced differential configuration also helps reduce substrate and source noise. This mixer is used as an IQ Mixer. The concept can be easily ported to other millimeter wave frequency of operation.

• Double balanced differential configuration
• Low noise figure : 10-20 dB @1 KHz; 10 dB@100 KHz
• Conversion gain: 0-10 dB
• Low current consumption: 10-30 mA
• IIP3 : 0-10 dBm
• Input return loss : 15 dB

Block Diagram