Passive Frequency Doubler with Excellent f0 Isolation
Custom MMIC has expanded its portfolio of high performance MMIC doublers with the CMD226C3. The MMIC design doubles an input frequency between 7 and 11 GHz to an output from 14 to 22 GHz.
The CMD226C3 has low conversion loss and excellent f0 isolation. With an input drive level of +15 dBm at 9 GHz, the typical conversion loss is 9 dB and f0 isolation is 44 dB below the input level. Typical 3f0 and 4f0 isolation are 48 and 50 dB, respectively. Extremely temperature stable, conversion gain versus frequency varies less than 2 dB over the operating temperature range of −40°C to +85°C. Conversion gain is also stable with varying drive.
A passive GaAs design, the doubler has low phase noise and does not require biasing. Housed in a ceramic, QFN-style package, the broadband doubler is designed for 50 Ω systems, with the input return loss better than 6 dB, which occurs at the low end of the input frequency band. The output return loss is better than 5 dB, with the peak also at the low end of the output frequency range.
An evaluation printed circuit board (PCB) is available to speed testing of the CMD226C3. The doubler is also available in die form for integration in chip-and-wire assemblies.
The low phase noise of the passive design makes the doubler particularly useful for local oscillator (LO) chains in radar, switched multimegabit data service (SMDS), satellite communications and point-to-point radio for cellular backhaul and data networks.