The document introduces the reference circuits of Circuit Note CN-0243 Circuits from the Lab™, which are engineered and tested to help solve analog, mixed-signal, and RF design challenges. The document provides detailed information about the connected and referenced devices, as well as the high dynamic range RF transmitter signal chain using a single external frequency reference for DAC sample clock and IQ modulator LO generation.
This document presents a high dynamic range RF transmitter signal chain design utilizing the ADRF6702 IQ modulator, AD9122 dual 16-bit DAC, and AD9516 clock generator. The design supports both Zero IF (ZIF) and Complex IF (CIF) configurations and is engineered for integration with the Lab™ reference circuits system.
The note details the circuit description, focusing on the ADRF6702's divide-by-2 LO architecture which simplifies PCB layout by eliminating the need for external filters between the synthesizer and modulator. It also discusses the importance of the DAC/modulator passive interface filter and provides guidance on PCB layout for the filter section to ensure optimal performance.
It serves as a high dynamic range RF transmitter signal chain using a single external frequency reference for DAC sample clock and IQ modulator LO generation.
The AD9122 has an option of up to 8x interpolation.