Can LTC5553 support real-time bandwidth above 5GHz?

I use TI’s DAC38RF82, which is similar to AD9161. Both are RF DACs. The real-time bandwidth of RF82 reaches 2GHz. My LO uses lmx2595 with a frequency range of 1~20GHz. After mixing with LTC5553, I will keep the double-sideband signal.

I need a large bandwidth signal to carry out signal suppression interference experiments, which interfere with all signals with a frequency between 6~9GHZ.

Question 1: Can the LTC5553 mixer support a real-time bandwidth of 5GHz?

Question 2: LTC5553 includes a band-pass filter with a range of 3~20GHz. My IF intermediate frequency is lower than 3GHz. After mixing, is the power of the IF component in the RF still high?

  • 0
    •  Analog Employees 
    on Mar 5, 2021 4:20 PM

    Hi edamy, 

    I am sure the LTC5553 team will respond soon. But I have a comment on the RF DAC comparison: the DAC38RF82 is TI's version of ADI's AD917x dual DAC. AD917x is 12GSPS compared to DAC38RF82's 9GSPS. There are other differences in performance, with AD917x typically performing better (not at all a biased view, despite this being an ADI forum :) ). The AD9161 is an exportable (US export control laws) version of AD9162 and AD9164, which are single DACs without a built in PLL - the simplified clocking allows some of the lowest residual phase noise in the industry:

    Improved DAC Phase Noise Measurements Enable Ultralow Phase Noise DDS Applications | Analog Devices

    AD9176 can support iBW of >3GHz @ 16bit resolution. May be worth considering to pair with the LTC5553 :)


  • +1
    •  Analog Employees 
    on Mar 18, 2021 10:43 PM

    The LTC5553 is a wideband double-balanced mixer designed for very wide signal bandwidth. It's IF port is internally matched from 500MHz to 9GHz with excellent return loss. The RF port is also internally matched with reasonable return loss across the entire bandwidth of 3-20GHz. A small shunt capacitor can improve matching at high frequencies.

    There is no internal bandpass filter on LTC5553. However, its on-chip RF balun has a bandpass frequency response. The LTC5553's IF to RF isolation is >40dB typical for IF from 500MHz to 9GHz.