QFE1520/1550, QFE2520/2550 Design Guidelines

119 Pages·2014·3.074 MB·English

by  Qualcomm Technologies Inc.

Design Guidelines
QFE1520/1550,
QFE2520/2550
80-NL732-5 Rev. B

Confidential and Proprietary – Qualcomm Technologies, Inc.
Restricted Distribution: Not to be distributed to anyone who is not an employee of either Qualcomm
or its subsidiaries without the express approval of Qualcomm’s Configuration Management.
Confidential and Proprietary – Qualcomm Technologies, Inc.
NO PUBLIC DISCLOSURE PERMITTED: Please report postings of this document on public servers or websites to: [email protected].
Restricted Distribution: Not to be distributed to anyone who is not an employee of either Qualcomm or its subsidiaries without the express approval of Qualcomm’s
Configuration Management.
Not to be used, copied, reproduced, or modified in whole or in part, nor its contents revealed in any manner to others without the express written permission of Qualcomm
Technologies, Inc.
Qualcomm is a trademark of QUALCOMM Incorporated, registered in the United States and other countries. All QUALCOMM Incorporated trademarks are used with
permission. Other product and brand names may be trademarks or registered trademarks of their respective owners.
This technical data may be subject to U.S. and international export, re-export, or transfer (“export”) laws. Diversion contrary to U.S. and international law is strictly prohibited.
Qualcomm Technologies, Inc.
5775 Morehouse Drive
San Diego, CA 92121
U.S.A.
© 2014 Qualcomm Technologies, Inc.
Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 2
Revision History
Revision Date Description
A June 2014 Initial release
B August 2014 Slide 33: Updated and added module design package of 1-2-1 and 2-4-2 layer stacks
Slide 83: Updated and added module design package of 1-2-1 and 2-4-2 layer stacks
Slide 97: Updated QFE1520 CPL_OUT to NC and added best layout option
Slide 98: Updated QFE2520 CPL_OUT to NC and added best layout option
Slide 99: Added QFE1550 best layout option
Slide 100: Added QFE2550 best layout option
Slides 105–108: Updated schematic part designations and added the CAD design
Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 3
Contents
1 Introduction 5
1.1 Overview of Antenna Impedance Tuning 6
1.2 QFEx5x0 Devices Introduction 12
1.3 QTI Support for Qtuner device 29
2 Antenna Impedance Tuning Overview 35
3 Antenna Impedance Tuning Methods 42
3.1 Open-loop 45
3.2 Advanced Open-loop 47
3.3 Closed-loop 51
4 Antenna Tuning Design Procedure 57
4.1 QTI Reviews and Design Support 58
4.2 Process Overview 60
5 Introduction to Antenna Tuning Software 62
5.1 Characterization 65
5.2 Calibration 68
5.3 QTI Sweep Tools 70
6 Hardware Design Guidelines 82
6.1 Coupler Design Considerations 85
6.2 Maximum Voltage Swings 93
6.3 Reference Schematics 96
6.4 RF Layout Rules 101
6.5 Support Circuits 109
6.6 DC Power Line Rules 115
Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 4
Section 1
1.1 Overview of Antenna Impedance Tuning 6
Introduction 1.2 QFEx5x0 Devices Introduction 12
1.3 QTI Support for Qtuner device 29

Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 5
Section 1.1
Overview of Antenna

Impedance Tuning
Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 6
RF Front-end using the QFEx5x0
Simplified, generic RF configuration shown – not application or RFIC specific
Average VPH_PWR
power ernt
tracking VREG_xx & owme
sp
PRx MB & C e
yg
pport HB LNAs B&y GpaSsMs clock PMImarana
Su & SWs VDDs prim
s
ANT_0 Tuner HLBB GHB Tx driver circuiterters Envelope
Support DET GLB amplifiers band pconv tracking
eu
WTR as Support
B
RFIC
Modem
& s
PLRNxA LsB ers cuit IC
ertcir
vd
nn
oa
cb
ne
PDET & owas
ET Rx Db
Reconfigurable antenna impedance tuner device
QFE1520/QFE2520
The subject of this document
‘QFEx5x0' for common information
Sec. 1.1 Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 7
Antenna Impedance Tuning
Problem description
Static and dynamic variations cause mismatch losses that result in reduced Tx power and receiver sensitivity

Static variations: Fixed mismatch introduced during development; difficult to overcome – band, antenna, and

PA dependent
Dynamic variations: User-induced by holding the phone different ways; impossible to overcome in product

design

Solution – reconfigurable antenna impedance tuning
The Qtuner can reduce the mismatch loss and maximizes power transfer between the radio front-end and the

antenna in both Tx and Rx directions
The antenna tuner software feature enables Qualcomm Technologies, Inc. (QTI) customers to control

antenna matching using either closed or open-loop techniques to improve efficiency.
Sec. 1.1 Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 8
Static and Dynamic Variations
Antenna Front-end module domain
Loss in RF performance
due to mismatch between
antenna and FEM
Freespace Approx. -1 dB
Human body phantoms
Up to -3 dB
(head and hand)
Terminal Network
cost cost
Real-life (many
Up to -7 dB
user conditions)
1 dB loss in RF = 14% more sites
performance for same coverage
Source Vodafone: iwpc workshop 2011

Sec. 1.1 Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 9
Performance Improvement using Impedance Tuning
High volume commercial phone example

The power delivered to the antenna is plotted

Antenna efficiency and absorption loss is not taken into account


→

)
m
B
d
(

a
n
n
e
t
n
a

+4 dB o
t

d
e
r
e
v
i
l
e
d

r
e
w
Measured sample number → o
P
Without impedance tuning: With QFE1520 impedance tuning:
Spread = 6.58 dB Spread = 1.95 dB
 
Max = 29.37 dBm Max = 28.75 dBm
 
Min = 22.79 dBm Min = 26.80 dBm
 

Sec. 1.1 Confidential and Proprietary – Qualcomm Technologies, Inc. | MAY CONTAIN U.S. AND INTERNATIONAL EXPORT CONTROLLED INFORMATION | 80-NL732-5 Rev. B 10