I/Q (Inphase and quadrature) demodulation circuit

  • Thread starter Thread starter kent
  • Start date Start date
  • Tags Tags
    Circuit
Click For Summary
SUMMARY

The discussion focuses on building an I/Q demodulation circuit operating at 20 MHz. The AD8333 chip from Analog Devices is identified as a potential component, although its small size (5mm x 5mm) presents challenges for PCB integration. Participants suggest using a split local oscillator (LO) at 90 degrees to feed two mixers, with the intermediate frequencies (IFs) connected to two analog-to-digital converters (ADCs). This approach emphasizes the need for coding on a microcontroller (MCU) to complete the circuit functionality.

PREREQUISITES
  • Understanding of I/Q demodulation techniques
  • Familiarity with RF mixer components
  • Knowledge of PCB design for small form-factor components
  • Experience with microcontroller programming for signal processing
NEXT STEPS
  • Research the specifications and applications of the AD8333 chip
  • Learn about PCB design techniques for small SMT components
  • Explore RF mixer configurations for I/Q demodulation
  • Study programming techniques for microcontrollers in signal processing applications
USEFUL FOR

Electronics engineers, RF circuit designers, and hobbyists interested in building I/Q demodulation circuits and integrating advanced components into compact designs.

kent
Messages
13
Reaction score
0
Hi guys

I want to build a I/Q demodulation circuit...operate at 20MHz...does anyone have any experience on building this circuit in a similar frequency range? what kind of opamp + mixer shall I go for? There are too many parts I don't even know where to start from...

I have browsed through the Analog Device website and seems like there is an AD8333 chip that can do the trick for me...but the problem is that the size of the chip is extremely small...(5mm x 5mm)...and I don't know how to put that on a PCB...

here is the link to the AD8333 chip: http://www.analog.com/en/prod/0%2C28...8333%2C00.html

Thanks!
 
Last edited by a moderator:
Engineering news on Phys.org
Yea those chips are even smaller than SMT, and can only be soldered with robotic machines on an assembly line. As the industry pushed the envelope with digital demodulation, small chips are very common.

But for 20 MHz, you could cook up small demodulator using a split LO by 90 degrees and feed them to two mixers whose RF input is evenly split. The IF's would need to be hooked up to two ADC's. Then rest is coding on an MCU or what not.
 

Similar threads

Building a circuit which involves with a AD9854 DDS
  • · Replies 5 ·
Replies
5
Views
3K