DC2091A - Demo Manual

DEMO MANUAL DC2091A
LTC5599
30MHz to 1300MHz Low Power
Direct Quadrature Modulator
Description
Demonstration circuit 2091A is optimized for evaluation
of the LTC®5599 low power direct quadrature modulator.
The balanced I and Q baseband input ports can be either
AC- or DC-coupled to a source with a common mode voltage level of about 1.4V. Fixed LC networks on the LO and
RF ports cover a continuous 90MHz to 1300MHz range.
The SPI interface controls the supply current, modulator
gain, and allows optimization of the LO carrier feedthrough
and side-band suppression.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2091A
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
QuikEval is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners.
Measurement Setup
BB SIGNAL SOURCE
(VCMBB = 1.4VDC)
I+
I–
Q+
Q–
–6dB
–3dB
LO SIGNAL
SOURCE
SPECTRUM
ANALYZER
–
+
DC POWER SUPPLY
(3.3V)
DC2091 F01
Figure 1. Test Setup for RF Performance Measurements
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DEMO MANUAL DC2091A
Absolute Maximum Input Ratings
Supply Voltage..........................................................3.8V
Common Mode Level of BBPI, BBMI,
and BBPQ, BBMQ....................................................2V
LOL, LOC DC Voltage.............................................. ±0.1V
LOL, LOC Input Power..........................................20dBm
Voltage on Any Pin............................–0.3V to VCC + 0.3V
TJMAX..................................................................... 150°C
Case Operating Temperature Range........ –40°C to 105°C
Storage Temperature Range................... –65°C to 150°C
CAUTION: This part is sensitive to electrostatic discharge (ESD). Observe proper ESD
precautions when handling the LTC5599.
Notes on Test Equipment and Setup
• Use high performance signal generators with fully
configurable differential I and Q outputs, such as the
Rohde & Schwarz SMJ100A vector signal generator or
equivalent.
• Use narrow resolution bandwidth (RBW) and engage
video averaging on the spectrum analyzer to lower the
displayed average noise level (DANL) in order to improve
sensitivity and to increase dynamic range. The trade-off
is increased sweep time.
• Spectrum analyzers can produce significant internal distortion products if they are overdriven. Generally, spectrum
analyzers are designed to operate at their best with about
–30dBm to –40dBm at their input filter or preselector.
Sufficient spectrum analyzer input attenuation should be
used to avoid saturating the instrument, but too much
attenuation reduces sensitivity and dynamic range.
• Before taking measurements, the system performance
should be evaluated to ensure that:
1) clean input signals can be produced
2) the spectrum analyzer’s internal distortion is minimized
3) the spectrum analyzer has enough dynamic range
and sensitivity
4) the system is accurately calibrated for power and
frequency.
• Digital modulation often requires DC coupling and flat
frequency response. For best EVM performance with
complex modulation, the RC networks at the baseband
I/Q inputs are not required.
Quick Start Procedure
1. Remove the demonstration circuit from its protective
packaging in an ESD-safe working area.
2. Turn off the DC power supply as well as the baseband
and LO signal sources’ outputs.
3. Connect all test equipment as show in Figure 1.
4. Make sure jumper JP1 is installed and the jumper JP2
is installed at the 1-2 position.
5. Slowly increase the supply voltage to 3.3V. Do not
exceed 3.8V.
6. Turn on the baseband signal source. Set the baseband
common mode bias to 1.4V.
2
7. Verify the total VCC supply current is approximately
28mA. The demonstration circuit is now turned on
and is ready for measurements.
8. Turn on the output of the LO source and apply a
492.8MHz, 0dBm CW Signal.
9. Set the baseband signal source to provide a 100kHz,
200mVP-P(DIFF) baseband input signal. The I and Q
channels should be 90° shifted and set for lower
sideband selection.
10.Measure the modulator’s RF output on the Spectrum
Analyzer at 492.7MHz.
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DEMO MANUAL DC2091A
Quick Start Procedure
11.Calculate the Voltage Conversion Gain:
Gain = 20 • log (VRF(OUT)(50Ω) / VIN(DIFF)(I OR Q))
12.Measure the Output 1dB Compression Point by increasing the input signal level until the Voltage Conversion
Gain degrades by 1dB.
13.Measure the Image Rejection at 492.9MHz.
15.Connect the DC590B to the DC2091A with the ribbon
cable provided. Make sure jumper JP6 on the DC590B
is set to 3.3V.
16.Run QuikEval® to start the GUI associated with the
LTC5599.
17.The turn off procedure is the reverse of the turn on
procedure. Make sure VCC is removed after VEN.
14.Measure the LO Leakage at 492.8MHz.
Demo Board Schematic
VCC
3.3V
GND
EN
E1
FB1
330Ω AT
100MHz
C1
4.7µF
E2
SDO
SDI
E3
2
VCTRL
VCC
E4
JP1
1
R1, 1Ω
2
J1
L1, 39nH
C5, 15pF
CS
25
24 23 22 21 20 19
GND VCC EN SDO SDI SCLK CSB
C3
0.1µF
1
LO
SCLK
C2, 1000pF
VCTRL
GNDRF
GND
GNDRF
3 LOL
LTC5599IUF
4 LOC
5 GND
TTCK
TEMP
BBMI
BBPI
E5
GNDRF
GNDRF
GNDRF
6 TTCK
C4
0.01µF
17
J2
16
15
14
13
J4
R4, 0Ω
R6, 0Ω
J6
J3
R3, 0Ω
R5, 0Ω
J5
R2, OPT
E7
RF
TEMP BBPI BBMI BBPQ BBMQ GND
8
7
9
10
12
11
E6
R8
49.9Ω
GND
RF
18
C6
0.1µF
BBMQ
BBPQ
R12, OPT
R9
49.9Ω
C7
0.1µF
*
R10
49.9Ω
C8
0.1µF
R11
49.9Ω
*
C9
0.1µF
DC2091 F02
* REMOVE THE RC NETWORK FOR BEST EVM WITH COMPLEX DIGITAL MODULATION.
Figure 2. Low Power I/Q Modulator Schematic
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DEMO MANUAL DC2091A
Demo Board schematic
VCC
U5
NC7WZ17P6X
VCC_L
R22
200k
1
2
3
1
R23
1k
6
C10
2.2pF
3
JP1
4
CS
R25
1k
SCLK
VCC_L
2
E8
VCC_L
GND
VCC
C12
2.2pF
5
C11
0.1µF
U3
NC7WZ17P6X
R26
1k
6
1
C13
2.2pF
3
4
2
5
SDI
VCC_L
GND
VCC
C14
0.1µF
P1
HD-2X7.0.79
ISO_7V_UNREG
ISO_5V_3p3v_REG
ISO_CSb
ISO_SCK_SCL
ISO_SDA_MOSI
ISO_MISO
EE_VCC
EE_SDA
EE_SCL
EE_GND
ISO_GND
ISO_GND
3
8
13
ISO_GND
GPI01
U4
74LVC1T45GW
1
2
1
6
C15
0.1µF 2
4
7
R20
100Ω
5
VCC_A
GND
VCC_B
DIR
6
C17
0.1µF
C16
0.1µF
5
R18
4.99k
R19
1k
4
3
VCC_L
VCC_L
C18
2.2pF
10
9
SDO
11
12
U2
24LC025
14
R15
4.99k
R14
4.99k
R13
4.99k
8 V
CC
7 WP
A0
6 SCL
5 SDA
A2
A1
VSS
1
2
3
4
DC2091 F03
Figure 3. Demo Board SPI Interface
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DEMO MANUAL DC2091A
Parts List
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
1
C1
CAP., X5R, 4.7µF, 10%, 16V, 0603
MURATA, GRM188R61C475KAAJD
2
1
C2
CAP., C0G, 1000pF, 5%, 50V, 0402
MURATA, GRM1555C1H102JA01D
3
10
C3, C6–C9, C11, C14–C17 CAP., X7R, 0.1µF, 10%, 16V, 0402
MURATA, GRM155R71C104KA88D
4
1
C4
CAP., X7R, 0.01µF, 10%, 16V, 0402
MURATA, GRM155R71C103KA01D
5
1
C5
CAP., COG, 15pF, 5%, 50V, 0402
MURATA, GRM1555C1H150JA01D
6
4
C10, C12, C13, C18
CAP.,COG, 2.2pF,+/-.1pF, 25V, 0402
MURATA, GRM1555C1E2R2BZ01D
7
5
E1, E2, E3, E7, E8
TESTPOINT, TURRET, .094"
MILL-MAX, 2501-2-00-80-00-00-07-0
8
3
E4, E5, E6
TESTPOINT, TURRET, .063"
MILL-MAX, 2308-2-00-80-00-00-07-0
9
1
FB1
FERRITE BEAD, 33Ω @100MHz
TDK, MPZ1608S331AT
10
1
JP1
HEADER, 2 PIN, 0.079 SINGLE ROW
SULLINS, NRPN021PAEN-RC
11
1
JP2
HEADER, 3 PIN, 0.079 SINGLE ROW
SULLINS, NRPN031PAEN-RC
12
2
XJP4, XJP5
SHUNT, 2mm Ctrs.
SAMTEC, 2SN-BK-G
13
6
J1–J6
CONN., SMA, 50Ω, EDGE-LANCH
E.F.JOHNSON, 142-0701-851
14
1
L1
IND., 39nH, 0402HP
COILCRAFT, 0402HP-39NXJLU
15
1
P1
HEADER, 2X7PIN, 0.079CC
MOLEX, 87831-1420
16
1
R1
RES., CHIP, 1Ω, 1%, 0402
VISHAY, CRCW04021R00FNED
17
0
R2, R12
OPT, 0402
18
4
R3, R4, R5, R6
RES., CHIP, 0Ω, 0402
VISHAY, CRCW04020000Z0ED
19
4
R8, R9, R10, R11
RES., CHIP, 49.9Ω, 1%, 0402
VISHAY, CRCW040249R9FKED
20
3
R13, R14, R15
RES., CHIP, 4.99K, 1%, 0402
VISHAY, CRCW04024K99FKED
21
5
R18, R19, R23, R25, R26
RES., CHIP, 1K, 1%, 0402
VISHAY, CRCW04021K00FKED
22
1
R20
RES., CHIP, 100Ω, 1%, 0402
VISHAY, CRCW0402100RFKED
23
1
R22
RES., CHIP, 200K, 1%, 0402
VISHAY, CRCW0402200KFKEA
24
1
U1
IC., LTC5599, QFN-24-4X4
LINEAR TECHNOLOGY, LTC5599IUF#PBF
25
1
U2
IC, EEPROM 2KBIT 400KHZ 8TSSOP
MICROCHIP TECH., 24LC025-I/ST
26
2
U3, U5
I.C., DUAL BUFFER SCHMT TRIG UHS SC706
FAIRCHILD SEMI., NC7WZ17P6X
27
1
U4
I.C., DUAL TRANSCEIVER 3ST 6TSSOP
NXP, 74LVC1T45GW,125
28
1
FAB, PRINTED CIRCUIT BOARD
DEMO CIRCUIT DC2091A
dc2091afa
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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DEMO MANUAL DC2091A
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual 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 THE 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. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. 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. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
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Linear Technology Corporation
LT 1115 REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2014
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