Texas Instruments TRF3701 User manual

TRF3701/TRF3702
Quadrature Modulator
Evaluation Module
2004 Wireless Infrastructure Products
User’s Guide
SLWU007

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Copyright 2004, Texas Instruments Incorporated

EVM IMPORTANT NOTICE
Texas Instruments (TI) provides the enclosed product(s) under the following conditions:
This evaluation kit being sold by TI is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION
PURPOSES ONLY and is not considered by TI to be fit for commercial use. As such, the goods being provided
may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective
considerations, including product safety measures typically found in the end product incorporating the goods.
As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic
compatibility and therefore may not meet the technical requirements of the directive.
Should this evaluation kit not meet the specifications indicated in the EVM User’s Guide, the kit may be returned
within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE
WARRANTY MADE BY SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED,
IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY
PARTICULAR PURPOSE.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user
indemnifies TI from all claims arising from the handling or use of the goods. Please be aware that the products
received may not be regulatory compliant or agency certified (FCC, UL, CE, etc.). Due to the open construction
of the product, it is the user’s responsibility to take any and all appropriate precautions with regard to electrostatic
discharge.
EXCEPT TO THE EXTENT OF THE INDEMNITY SET FORTH ABOVE, NEITHER PARTY SHALL BE LIABLE
TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
TI currently deals with a variety of customers for products, and therefore our arrangement with the user is not
exclusive.
TI assumes no liability for applications assistance, customer product design, software performance, or
infringement of patents or services described herein.
Please read the EVM User’s Guide and, specifically, the EVM Warnings and Restrictions notice in the EVM
User’s Guide prior to handling the product. This notice contains important safety information about temperatures
and voltages. For further safety concerns, please contact the TI application engineer.
Persons handling the product must have electronics training and observe good laboratory practice standards.
No license is granted under any patent right or other intellectual property right of TI covering or relating to any
machine, process, or combination in which such TI products or services might be or are used.
Mailing Address:
Texas Instruments
Post Office Box 655303
Dallas, Texas 75265
Copyright 2004, Texas Instruments Incorporated

EVM WARNINGS AND RESTRICTIONS
It is important to operate this EVM within the input and output voltage ranges described in the
EVM user’s guide.
Exceeding the specified input range may cause unexpected operation and/or irreversible
damage to the EVM. If there are questions concerning the input range, please contact a TI
field representative prior to connecting the input power.
Applying loads outside of the specified output range may result in unintended operation and/or
possible permanent damage to the EVM. Please consult the EVM User’s Guide prior to
connecting any load to the EVM output. If there is uncertainty as to the load specification,
please contact a TI field representative.
During normal operation, some circuit components may have case temperatures greater than
60°C. The EVM is designed to operate properly with certain components above 60°C as long
as the input and output ranges are maintained. These components include but are not limited
to linear regulators, switching transistors, pass transistors, and current sense resistors. These
types of devices can be identified using the EVM schematic located in the EVM User’s Guide.
When placing measurement probes near these devices during operation, please be aware
that these devices may be very warm to the touch.
Mailing Address:
Texas Instruments
Post Office Box 655303
Dallas, Texas 75265
Copyright 2004, Texas Instruments Incorporated

-3
Read This First
Preface
Read This First
About This Manual
This user’s guide describes the configuration of the of the TRF3701/2
evaluation module (EVM), modes of operation, function, and the physical
characteristics.
How to Use This Manual
This document contains the following chapters:
Chapter 1 - Overview
Chapter 2 - Physical Description
Chapter 3 - Circuit Description
Chapter 4 - Circuit Board Test Points
Chapter 5 - Schematic
Information About Cautions and Warnings
This book may contain cautions and warnings.
This is an example of a caution statement.
A caution statement describes a situation that could potentially
damage your software or equipment.
This is an example of a warning statement.
A warning statement describes a situation that could potentially
cause harm to you.

-4
The information in a caution or a warning is provided for your protection.
Please read each caution and warning carefully.
FCC Warning
This equipment is intended for use in a laboratory test environment only. It gen-
erates, uses, and can radiate radio frequency energy and has not been tested
for compliance with the limits of computing devices pursuant to subpart J of
part 15 of FCC rules, which are designed to provide reasonable protection
against radio frequency interference. Operation of this equipment in other en-
vironments may cause interference with radio communications, in which case
the user at his own expense will be required to take whatever measures may
be required to correct this interference.

-5
Contents
Contents
1 Overview 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Purpose 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 EVM Circuit Overview 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Power Requirements 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 TRF3701/02 EVM Operating Procedure 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Physical Description 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 PCB Layout 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Parts List 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Circuit Description 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Circuit Function 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.1 Differential/Single-Ended Inputs via Buffer Amplifiers 3-2. . . . . . . . . . . . . . . . . . . . .
3.1.2 Differential/Singled-Ended Inputs Without Buffer Amplifier 3-2. . . . . . . . . . . . . . . .
3.1.3 Power Down 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.4 Input Pins Bias 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.5 Power 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Circuit Board Test Points 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Circuit Board Test Point Locations 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 Schematics 5-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-6
Figures
2-1 Top Layer 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2 Layer 2—Ground Plane 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-3 Layer 3—Power Plane 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-4 Bottom Layer 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-1 Silkscreen Top Layer—Test Points Location 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-2 Bottom Layer—Test Points Location 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tables
1-1 EVM Configuration 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-1 Parts List 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-1 Power Supply J1 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2 CM Bias Voltage 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-3 CM Bias Voltages via Op Amp 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-1
Overview
Overview
This document relates to the TRF3701/TRF3702 direct launch quadrature
modulator for applications in the transmit path of base stations and
communications equipment. The TRF3701 operates between 400 MHz and
1.5 GHz and the TRF3702 between 1.5 GHz and 2.5 GHz. A quadrature
modulator is used for up conversion of signals from the transmit chain DAC to
the RF power amplifier device. Evaluating a modulator complex performance
involves careful bias voltage setup, an LO signal and at least two signals (I/Q)
at the input to the modulator. This document describes the wide range of test
options available with this EVM and the factors that must be considered in
using the EVM.
Topic Page
1.1 Purpose 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 EVM Circuit Overview 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Power Requirements 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 TRF3701/2 EVM Operating Procedure 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 1

Purpose
1-2
1.1 Purpose
The TRF3701/TRF3702 evaluation module (EVM) is intended for the
evaluation of the TRF3701 and TRF3702 direct launch quadrature modulator.
Unless otherwise stated, the functionality described in this manual applies to
both the TRF3701 and TRF3702 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 and Table 1-1.
The EVM has an option for differential I/Q input signals via the two THS4503
op amps as shown in the schematic and Table 1-1. The THS4503 (U2, U3)
provides single-ended/differential inputs and outputs in an 8-pin package. The
device has a unity gain bandwidth of 370 MHz, a slew rate of 2800 V/µs, and
a IMD3 –95 dBc at 30 MHz. The outputs from U2 and U3 are applied to the
TRF3701/TRF3702 quadrature modulator IC.
The I signals are connected to J4 (I+) and J8 (I-), respectively. The Q signals
are connected to J5 (Q+) and J11 (Q-), respectively. The LO signal is fed to
J2 and the SMA connector J3 is used to monitor the output signal from the
quadrature modulator (U1).
The quadrature modulator requires a supply voltage of 5 V / 145 mA from a
regulated power supply. Both the amplifiers (U2, U3) and the
TRF3701/TRF3702 are powered from external power supplies connected to
connector J1. The op amp supply voltage must not exceed ±7.5 V.
The TRF3701/TRF3702 quadrature modulator requires a dc common mode
bias voltage (3.7 Vdc) on all four input pins. Power supply connectors J6 and
J13 accepts these voltages from an external power supply.
1.3 Power Requirements
The EVM has three dc-power supply connectors: J1 accepts ±7 V for op amp
supply and a VCC of 5 V for the TRF3701/TRF3702. J6 accepts the
VCM (3.7 V) common-mode bias voltage for the TRF3701/TRF3702. J13
accepts the VCM (3.7 V) input signal common-mode bias when using op amps
U2 and U3.
Voltage Limits
Exceeding the ±7.5 V maximum may damage the THS4503 op amp.
Exceeding 5.6 V may damage the TRF3701/2

TRF3701/02 EVM Operating Procedure
1-3
Overview
1.4 TRF3701/02 EVM Operating Procedure
Set up the EVM as follows:
1) Verify all settings against Table 1-1.
Table 1-1.EVM Configuration
Configuration Table
Op-Amp No Op-Amp
Single-Ended Inputs Available – TRF370x Driven
Single-Endedly DC-Coupled Differential Inputs Available – TRF370x Driven Differentially (Default
Configuration)
W5 pins 1-2, W1, W3, W7, W8, W9, W10, R6, R7, R13,
R15, R12{, R14{, R17{, R18{, C53-C56{, W2{, W4{
Apply dc offset (VCM = 3.7 Vdc) to J13. Adjust VCOM1 and
VCOM2 externally to optimize.Apply I signal to J4, Q to J5.
W5 pins 1-2, W1{, W3{, W7{, W8, W9{W10, W2, W4,
R12-R15{, (C53 -C56)⇒replace with 0 Ω, (R29-R32)⇒if
50-Ωtermination required.
All dc offsets adjusted externally.
Apply I signal to J9, I to J7, Q to J12, Q to J10.
Differential Inputs Available – TRF370x Driven
Differentially DC-Coupled Single-Ended Inputs Available – TRF370x Driven Single-Endedly
W5 pins 1-2,W2, W4, W8, W10, R12-R15, R6{, R7{, R17,
R18, C53-C56{, W1{, W3{, W7{, W9{
Apply dc offset (VCM = 3.7 Vdc) to J13. Adjust VCOM1 and
VCOM2 externally to optimize. Residual dc can be applied
to op-amp inputs for adjusting the complementary inputs if
desired.
Apply I signal to J4, /I to J8, Q to J5 and /Q to J11.
W5 pins 1-2, W1, W3, W7{, W8, W9{, W10, W2{, W4{,
R12-R15{, (C54, C56)⇒replace with 0 Ω, C53{, C55{,
(R30, R32)⇒if 50-Ωtermination required.
Apply dc offset (VCM = 3.7 Vdc) to J6 and adjust R33 and
R34 to optimize the dc offset level of the complementary I,Q
inputs.
Apply I signal to J9, Q to J12.
Single-Ended Inputs Available – TRF370x Driven
Differentially AC-Coupled Single-Ended Inputs Available – TRF370x Driven Single-Endedly
W5 pins 1-2, W2, W4, W8, W10, R12-R15, R6, R7, R17{,
R18{, C53-C56{, W1{, W3{, W7{, W9{
Apply dc offset (VCM = 3.7 Vdc) to J13. Adjust VCOM1 and
VCOM2 externally to optimize. Residual dc can be applied
to op-amp inputs for adjusting the complementary inputs if
desired. In this case, follow the connections of the section
above (differential drive).
Apply I signal to J4, Q to J5.
W5 pins 1-2, W1, W3, W7, W8, W9, W10, W2{, W4{,
R12-R15{, C54, C56, C53{, C55{, (R30, R32)⇒if 50-Ω
termination required.
Apply dc offset (VCM = 3.7 Vdc) to J6 and adjust R33 and
R34 to optimize.
Apply I signal to J9, Q to J12.
AC-Coupled Differential Inputs Available –
TRF370x Driven Differentially
W5 pins 1-2, W1, W3, W7, W8, W9, W10, W2, W4,
R12-R15{, C54, C56, C53, C55, (R29-R32)⇒if 50-Ω
termination required.
Apply dc offset (VCM = 3.7 Vdc) to J6 and adjust R33 and
R34 to optimize.
Apply I signal to J9, I to J7, Q to J12, Q to J10.
†Remove from circuit
2) Connect the regulated power supplies to the EVM as follows:
a) Switch on the VCC (5 V) supply and verify that the current drawn is
approximately 130 - 140 mA.
b) Switch on the VCM (3.7 Vdc) precision regulated bias voltage supply
connected to J6 (if needed).

TRF3701/02 EVM Operating Procedure
1-4
c) Switch on the ±7-V op amp supply, then turn on the precision
regulated power supply connected to J13, set to VCM, and used to
provide the VCOM1 and VCOM2 voltages (if needed).
3) Use a suitable 50-Ωoutput signal generator to supply the LO signal:
0 dBm.
4) Use an arbitrary waveform generator to provide the I/Q input signals. A
typical setup is as follows: a 1-Vp-p sine wave, a frequency of 900 KHz,
a dc-offset of 0 V, and an output impedance 50-Ω.
5) Connect a spectrum analyzer to the SMA connector marked RFOUT (J3)
and monitor the TRF3701/TRF3702 output.
6) To optimize the carrier suppression, this modulator performs the following
(if using on-board dc offset through J3):
a) Connect a spectrum analyzer to output port J3, rotate R33 to decrease
the LO feed through as required.
b) Then rotate R34 to further decrease the LO feed through.
c) Repeat this procedure until you obtain the minimum LO feed through.
A typical optimized sideband suppression value is 60 dBc.
7) Use an arbitrary waveform generator to suppress the sideband. Adjust the
I/Q amplitude and phase of the CW signal coming from the arbitrary
waveform generator. A typical optimized side band suppression value is
60 dBc.

2-1
Physical Description
Physical Description
This chapter discusses the four layer PCB layout, component placement, and
list of components used on the evaluation module.
Topic Page
2.1 PCB Layout 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Parts Llists 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 2

PCB Layout
2-2
2.1 PCB Layout The EVM is constructed on a four layer, 76 mm x 76 mm x 1,575 mm thick PCB
using FR-4 material. Figure 2-1 through Figure 2-4 show the individual
layers.
Figure 2-1.Top Layer

PCB Layout
2-3
Physical Description
Figure 2-2. Layer 2—Ground Plane

PCB Layout
2-4
Figure 2-3.Layer 3—Power Plane

PCB Layout
2-5
Physical Description
Figure 2-4. Bottom Layer

Parts List
2-6
2.2 Parts List
Table 2-1.Parts List
Description Footprint Qty Part Number MFR Reference
Description Not Installed
47 µF, tantalum, 10%, 10 V 7343 5 10TPA47M Sanyo C43-C47
0.1 µF, 16 V, 10% capacitor 508 8 C6-C11, C48,
C49
0.1 µF, 16 V, 10% capacitor 603 6 ECJ-1VB1C104K Panasonic C12-C17
10 µF, 10 V, 10% capacitor 3528 5 GRM42X5R106K10 Murata C1-C5
0.01 µF, 50 V, 10%
capacitor 603 6 AVX C23-C28
1 pF, 50 V, 10% capacitor 603 6 AVX C18-C21, C50,
C51
1 µF, 16 V, 10% capacitor 1206 5 C33-C37
1800 pF, 50 V, 10%
capacitor 805 0 C22, C52
10 pF, 50 V, 10% capacitor 603 4 PCC120ACVCT AVX C29-C32
0.01 µF, 16 V, 10%
capacitor 805 5 C38-C42
Ferrite bead 1206 7 FB1-FB7
392-Ωresistor, 1/10 W, 1% 805 4 ERJ-6ENF392R0V Panasonic R8-R11
374-Ωresistor, 1/10 W, 1% 805 4 ERJ-6ENF374R0V Panasonic R4, R5, R17.
R18
402-Ωresistor, 1/10 W, 1% 805 0 ERJ-6ENF402R0V Panasonic R6, R7
56.2-Ωresistor, 1/16 W, 1% 1210 4 ERJ-13NF56R2 Panasonic R1-R3, R16
1-kΩ resistor, 1/16 W, 1% 603 4 ERJ-3EKF1.00K Panasonic R23-R26
49.9-Ωresistor, 1/16 W, 1% 603 0 ERJ-3EKF49R9V Panasonic R29-R32
22.1-Ωresistor, 1/10 W, 1% 805 0 Panasonic R12-R15
0-Ωresistor, 1/10 W, 1% 603 0 ERJ-3EKF0R00V Panasonic R27, R28
0-Ωresistor, 1/10 W, 1% 805 5 ERJ-6ENF0R00V Panasonic L1, C53-C56
10 kΩPot BOURNS_3296Y 2 3296Y-103 Bourns R33, R34
SMA connectors SMA_Jack 4 2262-0000-09 Macom J7, J9, J10, J12
3POS_header 3pow_jumper 1 TSW-150-07-L-S Samtec W5
2POS_header 2pos_jumper 1 TSW-150-07-L-S Samatec W6
2POS solder jumpers 8W1-W4, W7 -
W10
SMA connectors SMA_END_SMA 6 90F2624 Newark J2-J5, J8, J11
3-pin power connector 2 93F7124 Newark J6, J13
3-pin power mate 2 95F5347 Newark P6, P13
4-pin power connector 2 93F7125 Newark J1
4-pin power mate 1 95F5348 Newark P1
THS4503 8-SOP (D) 2 THS4502ID Texas
Instruments U2, U3
TRF3701 or TRF3702 16-RHC (QFN) 1TRF3701 or
TRF3702 Texas Instruments U1
Screws 4-40 screw 4

3-1
Circuit Description
Circuit Description
This chapter discusses the various functions of the EVM.
Topic Page
3.1 Circuit Function 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 3

Circuit Function
3-2
3.1 Circuit Function
Two quad sets of SMA connectors are provided on the EVM for inputting
differential I/Q signals via the op amp or directly to the input pins of
TRF3701/TRF3702. Connectors J4, J8, J5, and J11 are for connecting the I/Q
signals via the op amp, while connectors J7, J9, J10, and J12 are used to
directly connect the signal source I/Q signals to the TRF3701/TRF3702.
3.1.1 Differential/Single-Ended Inputs via Buffer Amplifiers
Connectors J4, J8, J5, and J11 are used to dc-couple differential signal pairs
I+, I- and Q+, Q- to the unity gain differential buffer amplifier U2 and U3. For
a gain of two, change the value of R8, R9, R10, and R11 to 825 Ω.
For single-ended input, the I-channel input signal can be applied to either J4
or J8. However, the EVM is configured to accept the single ended I-channel
signal on J4.
The Q-channel input is via J5.
3.1.2 Differential/Singled-Ended Inputs Without Buffer Amplifier
Direct I/Q inputs, without the op amp, are routed to the TRF3701/TRF3702
through another set of SMA connectors, namely: J7, J9, J10, and J12.
3.1.3 Power Down
The EVM has a 3-position jumper (W5) for controlling the operation of the
device. For normal operation W5 pins 1-2 are shorted. In power-down mode,
W5 pins 2-3 are shorted.
3.1.4 Input Pins Bias
The TRF3701/TRF3702 I/Q input pins common-mode bias voltage is provided
either through J6 and adjusted by potentiometers R33 and R34 or via the op
amp VCOM1 and VCOM2 inputs through J13.
3.1.5 Power
Power is supplied to the EVM via header J1. Header J1 is a Molex 861904
4-pin male connector, and allows easy connection to a standard bench power
supply through a Molex 860504 4-pin female connector. The connector pin
outs are listed in Table 3-1.