DEMO MANUAL DC1642A
LTM9003
12-Bit Digital Predistortion
Receiver Subsystem
Description
Demonstration circuit DC1642A is an evaluation board fea-
turing Linear Technology Corporation’s LTM
®
9003 12-Bit
predistortion receiver subsystem. DC1642A demonstrates
good circuit layout techniques and recommended external
circuitry for optimal system performance.
DC1642A comes with Linear Technology’s 12-bit LTM9003
receiver subsystem installed. The board includes output
LVDS buffers. DC1642A plugs into the DC890 data acqui-
sition demo board using an FT149 adapter card and the
output can be easily analyzed with Linear Technology’s
PScope™ data processing software, which is available
for no charge on our website at
http://www.linear.com.
Design files for this circuit board are available at
http://www.linear.com/demo
L,
LT, LTC, LTM, µModule, Linear Technology and the Linear logo are registered trademarks
and PScope is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
quick start proceDure
Validating the performance of the LTM9003 is simple
with DC1642A, and requires only two input sources, a
clock source, a computer, and a lab power supply. Refer
to Figure 1 for proper board evaluation equipment setup
and follow the procedure below:
1. Connect the power supply as shown in Figure 1. There
are on-board low-noise voltage regulators that provide
the supply voltage for the DC1642A. The entire board
and all components share a common ground. The power
supply should still be a low-noise lab power supply
capable of supplying at least 1A.
2. Provide an encode clock to the ADC via SMA connector
J7. Use a low-phase-noise clock source such as a filtered
RF signal generator or a high-quality clock oscillator.
Note:
Similar to having a noisy input, a high-jitter (phase
noise) encode clock will degrade the signal-to-noise ratio
(SNR) of the system.
3. Apply an RF input signal to the board. For best results,
use a low distortion, low noise signal generator with
sufficient filtering to avoid degrading the performance
of the receiver.
4. Apply an LO input signal to the board. Note that the
difference in frequency between this signal and the RF
signal will be the IF frequency resulting at the IF filter
and ADC input.
5. Observe the ADC output with the FT149 adapter card
connected to the DC890, a USB cable, a Windows
computer, and Linear Technology’s PScope data pro-
cessing software. Note that the DC890 will also require
an external 6V/1A power supply when receiving LVDS
outputs.
orDer options
Table 1. DC1642A Variants
DC1624 VARIANTS
1624A-AA
1624A-AB
PART NUMBER
LTM9003A-AA
LTM9003A-AB
SFDR
58.8dB
62.4dB
SUPPLY VOLTAGE
2.5V ADC, 3.3V Amplifier, 3.3V Mixer
2.5V ADC, 3.3V Amplifier, 5V Mixer
BANDPASS FILTER
184MHz Center, 125MHz Bandwidth
184MHz Center, 125MHz Bandwidth
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DEMO MANUAL DC1642A
quick start proceDure
Signal
Generator
HP 8644B
or Equivalent
BPF
*
Power Supply +5V at 200mA
Power Supply +3.3V at 1A
Signal
Generator
HP 8644B
or Equivalent
BPF
To FT149+
DC890B
RF Signal Generator
(HP 8644B) or Other
Low Phase Noise
Clock Source (e.g. DC1216)
BPF
*
Note:
Even a high-quality signal synthesizer
will still have noise and harmonics that should
be attenuated with a low-pass or band-pass
filter. For good-quality high order filters, see
TTE, Lark Engineering, or equivalent.
Figure 1. Proper Measurement Equipment Setup
Table 2. DC1642A Connectors and Jumpers
REFERENCE
J2 (Mode)
J3 (SHDN/OE)
J4 (Sense)
J5 (RF)
J6 (Mixer/Amplifier Enable)
J7 (CLK)
J9 (LO)
TP1 (External Reference)
TP2 (GND)
TP3 (3.3V)
TP4 (GND)
TP5 (5V)
FUNCTION
Output Format and Clock Duty Stabilizer Pin. Default is V
DD
.
Enables/Disables the ADC. Default is ON.
Reference Input to Adjust the Full-Scale Range of the DC1642A. Default is V
DD
.
Board RF Signal Input. Impedance-matched to 50Ω for use with lab signal generators.
Enables/Disables the RF Mixer and Amplifier. Default is ON.
Board Clock Input. Impedance-matched to 50Ω. Drive with a low-phase-noise clock oscil-lator or filtered sine wave
signal source.
Board LO Signal Input. Impedance-matched to 50Ω for use with lab signal generators.
Reference Input to Adjust the Full-Scale Range of the LTM9003. Connects to the SENSE pin; by default, tied to V
DD
for
internal reference.
DC Ground.
DC Supply Input (3.3VDC).
DC Ground.
DC Supply Input (5VDC).
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DEMO MANUAL DC1642A
quick start proceDure
Other Board Circuitry
Device U1 is an EEPROM device that is used by the PScope
software to identify the board and apply the correct set-
tings for the data collection.
Using PScope Software
PScope, downloadable from Linear Technology’s website
at
http://www.linear.com/software,
processes data from the
DC890 QuikEval II data acquisition board and displays FFT
and signal analysis information on the computer screen.
The on-board EEPROM U1 should enable automatic board
detection and auto-configuration of the software.
From the Configure menu in the toolbar, uncheck “Au-
todetect Device.” The default settings for DC1642A are
shown in Figure 2.
Figure 2. Entering the Correct Device Information for Your ADC. Select the Correct Parameters for the DC1642A. Under
Normal Conditions, PScope Should Automatically Recognize the Board and Adjust the Software Settings Accordingly
dc1642af
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DEMO MANUAL DC1642A
parts list
ITEM
QTY
REFERENCE
LTM9003CV, Demo Board #1642A
1
1
C4
2
4
C1, C2, C10, C44
3
10
C19, C27-C32, C34, C35, C36
4
1
C45
5
4
C5, C6, C8, C9
6
2
C3, C7
7
0
C37, C42
8
1
C39
9
1
C43
10
1
J1
11
4
J2, J3, J4, J6
12
3
J5, J7, J9
13
1
J8
14
1
L1
15
1
L5
16
0
R41
17
0
R52
18
3
R3, R13, R14
19
1
R50
20
6
R37, R42-R46
21
17
R17-R23, R28, R30-R35, R38-R40
22
4
R6, R8, R53, R54
23
3
R10, R24, R48
24
2
R12, R49
25
1
R47
26
3
R4, R5, R51
27
2
R1, R2
28
2
R7, R11
29
5
R25, R26, R27, R29, R36
30
1
R9
31
1
T2
32
5
TP1-TP5
33
1
U1
34
2
U3, U4
35
2
U5, U10
36
6
XJP2, XJP3, XJP4, XJP6 (See Drawing)
37
3
(Stand-Off)
38
2
LTM9003CV-AA, Demo Board #1642A-AA
1
1
DC1642AA
2
0
R15
3
1
R16
4
1
U2
5
1
LTM9003CV-AB, Demo Board #1642A-AB
1
1
DC1642AA
2
1
R15
3
0
R16
4
1
U2
5
1
PART DESCRIPTION
Capacitor, NPO, 8.2pF 50V, 0.25pF 0402
,
,
Capacitor, X5R, 0.01µF 16V, 0.1, 0402
,
Capacitor, X5R, 0.1µF 10V, 0.1, 0402
,
Capacitor, X5R, 10µF 6.3V, 0.2, 0805
,
Capacitor, X5R, 4.7µF 10V, 0.2, 0805
,
Capacitor, X7R, 0.1µF 16V, 0.1, 0603
,
Capacitor, DNI
Capacitor, NPO, 0.5pF 50V, 0.25pF 0402
,
,
Capacitor, NPO, 1pF 50V, 0.25pF 0402
,
,
Connector, HSMC, Mezzanine
Header, 3×2, 2mm
Connector, SMA Female Edge Mount
Header, 2×1, 2mm
Inductor, 3.9nH, 5%, 0402
Inductor, 2.7nH, 5%, 0402
Resistor, DNI
Resistor, 0.01, 1/16W, 0603
Resistor, 0Ω Jumper, 0805
Resistor, 0Ω Jumper, 1206
Resistor, 10Ω, 0.01, 1/4W, 1206
Resistor, 100Ω, 0.01, 39833, 0201
Resistor, 1000Ω, 0.01, 1/10W, 0603
Resistor, 100k, 0.01, 39829, 0402
Resistor, 10k, 0.01, 39829, 0402
Resistor, 32.4k, 0.01, 39829, 0402
Resistor, 4.99Ω, 0.01, 39829, 0402
Resistor, 49.9Ω, 0.01, 39829, 0402
Resistor, 499Ω, 0.01, 1/10W, 0603
Resistor, 4990Ω, 0.01, 39829, 0402
Resistor, 64.9k, 0.01, 39829, 0402
XFRMR, 1:1, SMT, SM-22
Turret
IC, Serial_EEPROM, TSSOP8
IC, RPTR, LVDS, OCTAL, SMT, TSSOP
IC, VREG, ADJ, 500MA, DFN
SHUNT
Stand-Off, Nylon, 0.25"
Stencil, Component & Solder Sides
General BOM
Resistor, DNI
Resistor, 0Ω Jumper, 0805
I.C., µModule
Printed Circuit Board
General BOM
Resistor, 0Ω Jumper, 0805
Resistor, DNI
I.C., µModule
Printed Circuit Board
MANUFACTURER/PART NUMBER
AVX/04025A8R2CAT2A
AVX/0402YC103KAT
AVX/0402ZD104KAT
AVX/08056D106MAT
AVX/0805ZD475MAT
AVX/0603YC104KAT
AVX/04025A0R5CAT2A
AVX/04025A1R0CAT2A
Samtec/ASP-122952-01
Samtec/TMM-103-02-L-D
E.F
.JOHNSON/142-0701-851
Samtec/TMM-102-02-L-S
Coilcraft/0402CS-3N9XJLW
Coilcraft/0402CS-2N7XJLW
Vishay, CRCW0603XXXX
Vishay, CRCW08050000ZOEA
NIC, NRC12ZOTR
Vishay, CRCW120610R0FNEA
Vishay, CRCW0201100RFNED
Vishay, CRCW06031K00FKEA
Vishay, CRCW0402100KFKED
Vishay, CRCW040210K0FKED
Vishay, CRCW040232K4FKED
Vishay, CRCW04024R99FKED
Vishay, CRCW040249R9FKED
Vishay, CRCW0603499RFKEA
Vishay, CRCW04024K99FKED
Vishay, CRCW040264K9FKED
Macom/MABA-007159-000000
Mill_Max/2308-2
Microchip/24LC025-I_ST
Fairchild/FIN1108
Linear Technology/LT1763CDE
Samtec 2SN-BK-G
Keystone/ 8831(Snap On)
Vishay CRCW08050000Z0EA
Linear Tech. Corp. LTM9003CV-AA
Demo Circuit 1642A
Vishay CRCW08050000Z0EA
Linear Tech. Corp. LTM9003CV-AB
Demo Circuit 1642A
dc1642af
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DEMO MANUAL DC1642A
schematic Diagram
dc1642af
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 representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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