Overview; Purpose; Evm Circuit Overview; Power Requirements - Texas Instruments TRF370315 User Manual

TRF3703 Quadrature Modulator Evaluation Module
1

Overview

This document relates to the TRF3703-33 and TRF3703-15 (hereinafter referred to as TRF3703) direct
quadrature modulator for applications in the transmit path of base stations and communications
equipment. The TRF3703 operates between 400 MHz and 4 GHz. The quadrature modulator is used for
upconversion of signals from the transmit chain DAC to the RF power amplifier device. Evaluating
modulator complex performance involves careful bias-voltage setup, an LO signal, and two differential
(I/Q) signals at the input of the modulator. This document describes the wide range of test options
available and the factors that must be considered in using this EVM.
1.1

Purpose

The TRF3703 evaluation module (EVM) is intended for the evaluation of the TRF3703-33 and
TRF3703-15 direct-launch quadrature modulators. Unless otherwise stated, the functionality described in
this manual applies to both the TRF3703-33 and TRF3703-15 devices.
1.2

EVM Circuit Overview

The EVM comes configured for differential I/Q input signals via four SMA connectors as shown in the
schematic, Figure
For the upper sideband, the I signals are connected to J4 (I+) and J3 (I–). The Q signals are connected to
J5 (Q–) and J6 (Q+). The LO signal is fed to SAM connector J1, whereas J2 must be terminated with 50 Ω
to ground. SMA connector J7 is used to monitor the RF output signal from the quadrature modulator (U1).
The quadrature modulator requires a supply voltage of 4.5 V–5.5V at 235 mA from a regulated power
supply through headers W1 and W2. The TRF3703-33 requires a 235-mA current limit, whereas the
TRF3703-15 requires 205 mA.
The TRF3703-33 and TRF3703-15 quadrature modulators require a dc common-mode bias voltage (3.3
VDC and 1.5 VDC, respectively) on all four input pins.
1.3

Power Requirements

The TRF3703 EVM requires two 5-V V
Header W1 supplies 5 V to the LO circuitry, and W2 supplies 5 V to the modulator circuitry.
Voltage Limits
Exceeding 5.6 V may damage the TRF3703.
SLWU042B – October 2006 – Revised August 2008
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14, and in Table 1.
dc power-supply connectors through headers W1 and W2.
CC
SLWU042B – October 2006 – Revised August 2008
CAUTION
TRF3703 Quadrature Modulator Evaluation Module
User's Guide
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