Linear Technology DC503A Quick Start Manual

DC503A DEMO BOARD QUICK START GUIDE
Description:
The DC503A demo circuit board is intended to demonstrate the capabilities of the LT5512
downconverting mixer IC for cable infrastructure applications.
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The LT 5512 (Figure 1) is a broadband high signal level mixer IC optimized for high linearity
downconverter applications including cable and wireless infrastructure. The IC includes a
differential LO buffer driving a double-balanced mixer. An integrated RF amplifier improves LO-
RF isolation and eliminates the need for precision external bias resistors.
The LT5512 is a high-linearity alternative to passive diode mixers. Unlike passive mixers, which
have conversion loss and require high LO drive level, the LT5512 delivers conversion gain and
requires significantly lower LO drive levels.
The DC503A demo board downconverts 1230MHz RF input to 270-870MHz IF output. The LO is
injected from the high-side between 1500MHz and 2100MHz.
Figure 1. LT5512 IC Block Diagram
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