MAXIM MAX5885EVKIT

19-2978; Rev 0; 9/03
MAX5885 Evaluation Kit
Ordering Information
PART
TEMP RANGE
MAX5885EVKIT
0°C to +70°C
Features
♦ Fast Evaluation and Performance Testing
♦ CMOS Compatible
♦ SMA Coaxial Connectors for Clock Input and
Analog Output
♦ 50Ω Matched Clock Input and Analog Output
Signal Lines
♦ Single-Ended to Differential Clock Signal
Conversion Circuitry
♦ Differential Current Output to Single-Ended
Voltage Signal Output Conversion Circuitry
♦ Full-Scale Current Output Configured for 20mA
♦ External 1.25V Reference Source Available
IC PACKAGE
♦ Fully Assembled and Tested
48 QFN-EP*
♦ Also Evaluates the 14-Bit MAX5884 and 12-Bit
MAX5883
*EP = Exposed pad.
Component List
DESIGNATION
C1
C2–C13
C14, C17,
C20, C25
C15, C18,
C21, C26
QTY
DESCRIPTION
0
Not installed, ceramic capacitor
(0603)
12
0.1µF ±10%, 10V X5R ceramic
capacitors (0402)
TDK C1005X5R1A104K or
Taiyo Yuden LMK105BJ104KV
4
4
47µF ±10%, 6.3V tantalum
capacitors (B)
AVX TAJB476K006R or
Kemet T494B476K006AS
10µF ±10%, 10V tantalum
capacitors (A)
AVX TAJA106K010R or
Kemet T494A106K010AS
4
1µF ±10%, 10V X5R ceramic
capacitors (0603)
TDK C1608X5R1A105K
C23, C24
0
Not installed, ceramic capacitor
(0805)
CLK, OUT
2
SMA PC-mount vertical connectors
IOUTP, IOUTN
2
Scope probe jacks
J1
1
2 x 20 pin surface-mount header
Samtec TSM-120-02-S-MT
C16, C19,
C22, C27
DESIGNATION
QTY
JU1
1
3-pin header
DESCRIPTION
JU2–JU5
4
2-pin headers
L1–L4
4
Chip bead core inductors
Panasonic EXC-CL-4532U1
R1, R2
2
49.9Ω ±0.1% resistors (0603)
IRC PFC-W0603R-03-49R9-B
R3
1
100Ω ±1% resistor (0603)
R4, R5, R6
0
Not installed, resistors (0603)
R7
1
2kΩ ±1% resistor (0603)
R8–R26
19
0Ω ±5% resistors (0402)
R27, R28
2
24.9Ω ±1% resistors (0402)
R29–R45
0
Not installed, resistors (0402)
T1, T3
2
Transformers
Mini-Circuits ADTL1-12
T2
1
Transformer
Coilcraft TTWB3010-1
TP1–TP4
4
PC test points, black
TP5
1
PC test point, red
U1
1
MAX5885EGM (48-pin QFN-EP)
U2
1
1.25V voltage reference (8-pin SO)
Maxim MAX6161AESA
None
5
Shunts (JU1–JU5)
None
1
MAX5885 PC board
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
Evaluates: MAX5883/MAX5884/MAX5885
General Description
The MAX5885 evaluation kit (EV kit) is a fully assembled
and tested circuit board that contains all the components necessary to evaluate the performance of the
MAX5885 16-bit parallel input, 200Msps, current-output, digital-to-analog converter (DAC). The EV kit operates with CMOS-compatible data inputs, a singleended clock input, and 3.3V power supplies for simple
board operation.
The MAX5885 EV kit can also be used to evaluate the
MAX5884 (14 bit) and the MAX5883 (12 bit).
Evaluates: MAX5883/MAX5884/MAX5885
MAX5885 Evaluation Kit
Component Suppliers
SUPPLIER
PHONE
FAX
WEBSITE
AVX
843-946-0238
843-626-3123
www.avxcorp.com
Coilcraft
847-639-6400
847-639-1469
www.coilcraft.com
IRC
361-992-7900
361-992-3377
www.irctt.com
Kemet
864-963-6300
864-963-6322
www.kemet.com
Mini-Circuits
718-934-4500
718-934-7092
www.minicircuits.com
Panasonic
714-373-7366
714-737-7323
www.panasonic.com
Samtec
800-726-8329
812-948-5047
www.samtec.com
Taiyo Yuden
800-348-2496
847-925-0899
www.t-yuden.com
TDK
847- 803-6100
847-390-4405
www.component.tdk.com
Note: Please indicate that you are using the MAX5885 when contacting these component suppliers.
Quick Start
Recommended Equipment
• Three 3.3V power supplies
• Function generator with low phase noise and low jitter for clock input (e.g., HP 8662A)
• 16-bit digital pattern generator for data inputs (e.g.,
Tektronix DG2020A)
• Spectrum analyzer (e.g., HP 8560E)
• Voltmeter
The MAX5885 EV kit is a fully assembled and tested surface-mount board. Follow the steps below for board
operation. Do not turn on power supplies or enable
signal generators until all connections are completed.
Procedure
1) Verify that a shunt is installed across pins 2 and 3
of jumper JU1 (DAC enabled).
2) Verify that shunts are not installed across jumpers
JU2, JU4, and JU5 (DAC uses the 1.2V on-chip
voltage reference).
3) Verify that a shunt is installed across jumper JU3.
4) Synchronize the digital pattern generator
(DG2020A) with the clock function generator (HP
8662A).
5) Connect the clock function signal generator to the
CLK SMA connectors on the EV kit.
6) Verify that the 16-bit digital pattern generator is
programmed for valid CMOS output voltage levels.
2
7) Connect the digital signal generator output to the
J1 input header connector on the EV kit board. The
input header pins are labeled for proper connection with the digital pattern generator (i.e., connect
bit 0 to the header pin labeled B0, connect bit 1 to
the header pin labeled B1, etc.).
8) Connect the spectrum analyzer to the OUT SMA
connector.
9) Connect a 3.3V power supply to the V_CLK pad.
Connect the ground terminal of this supply to the
CLKGND pad.
10) Connect a 3.3V power supply to the D_VDD pad.
Connect the ground terminal of this supply to the
DGND pad.
11) Connect a 3.3V power supply to the A_VDD pad.
Connect the ground terminal of this supply to the
AGND pad.
12) Turn on the three power supplies.
13) With a voltmeter, verify that 1.2V is measured at the
V_REF PC board pad on the EV kit.
14) Enable the clock function generator (HP 8662A)
and the digital pattern generator. Set the clock
function generator output power to 10dBm and the
frequency (fCLK) to less than or equal to 200MHz.
15) Use the spectrum analyzer to view the MAX5885
output spectrum or view the output waveform using
an oscilloscope.
Detailed Description
The MAX5885 EV kit is designed to simplify the evaluation of the MAX5885 16-bit, 200Msps, current-output
DAC. The MAX5885 operates with CMOS-compatible
_______________________________________________________________________________________
MAX5885 Evaluation Kit
(7dBm) is recommended or for a square wave, a minimum amplitude signal of 0.5VP-P is recommended.
The MAX5885 EV kit provides a header connector to
easily interface with a pattern generator, circuitry that
converts the differential current output to a singleended voltage signal, and circuitry to convert a usersupplied single-ended clock signal to a differential
clock signal required by the MAX5885. The EV kit circuit includes different options for supplying a reference
voltage to the DAC. The EV kit can operate with a single 3.3V power supply but also supports the use of
three separate 3.3V power supplies by dividing the circuit into digital, analog, and digital clock planes that
improve dynamic performance.
The MAX5885 requires a reference voltage to set the
full-scale analog signal output voltage. The DAC contains a stable on-chip bandgap reference of 1.2V that is
used by default. The internal reference can be overdriven by an external reference for gain control or to
enhance accuracy and drift performance.
Power Supplies
The MAX5885 EV kit can operate from a single 3.3V
power supply connected to the D_VDD, A_VDD, and
V_CLK input power pads and their respective ground
pads for simple board operation. However, three separate 3.3V power supplies are recommended for optimum
dynamic performance. The EV kit board layout is divided
into three sections: digital, analog, and digital clock.
Using separate power supplies for each section reduces
crosstalk noise and improves the integrity of the output
signal. When using separate power supplies, connect
each power supply across the D_VDD and DGND PC
board pads (digital), across the V_CLK and CLKGND PC
board pads (digital clock), and across the A_VDD and
AGND PC board pads (analog) on the EV kit.
CMOS Input Data
The MAX5885 EV kit provides a 0.1in 2 x 20 header (J1)
to interface a 16-bit CMOS pattern generator to the EV kit.
The header data pins are labeled on the board with their
appropriate data bit designation. Use the labels on the
EV kit to match the data bits from the pattern generator to
the corresponding data pins on header J1.
Clock Signal
The MAX5885 requires a differential clock input signal
with minimal jitter. The EV kit circuit provides singleended to differential conversion circuitry. The user must
supply a single-ended clock signal at the CLK SMA
connector.
The clock signal can be either a sine wave or a square
wave. For a sine wave, a minimum amplitude of 1.5VP-P
Reference Voltage Options
The MAX5885 EV kit features three ways to provide a
reference voltage to the DAC: internal, on-board external, and user-supplied external reference. Verify that a
shunt is not connected across jumper JU5 to use the
internal reference. The reference voltage can be measured at the V_REF pad on the EV kit. The EV kit circuit
is designed with an on-board 1.25V temperature-stable
external voltage reference source (U2, MAX6161) that
can be used to overdrive the internal reference provided by the MAX5885. Install a shunt across jumpers JU4
and JU5 to use the on-board external reference. The
user can also supply an external voltage reference in
the 0.125V to 1.25V range by connecting a voltage
source to the V_REF pad and removing the shunts
across jumpers JU4 and JU5. See Table 1 to configure
the shunts across jumpers JU4 and JU5 and select the
source of the reference voltage.
Full-Scale Current
The MAX5885 requires an external resistor to set the
full-scale output current. The MAX5885 EV kit full-scale
current is set to 20mA with resistor R7. Replace R7 to
adjust the full-scale output current. Refer to the
Reference Architecture and Operation section in the
MAX5885 data sheet to select different values for R7.
Table 1. Reference Voltage Selection
JU4 AND JU5 SHUNT
POSITIONS
Installed
VOLTAGE REFERENCE MODE
External 1.25V reference (U2)
connected to MAX5885 REFIO pin
Not installed
MAX5885 internal 1.2V bandgap
reference
Not installed
User-supplied voltage reference at
the V_REF pad (0.125V to 1.25V)
_______________________________________________________________________________________
3
Evaluates: MAX5883/MAX5884/MAX5885
data inputs, a differential clock input signal, an internal
1.2V reference voltage, and a 3.3V power supply for
simple board operation.
Evaluates: MAX5883/MAX5884/MAX5885
MAX5885 Evaluation Kit
Differential Output
The MAX5885 complementary current outputs are terminated into differential 50Ω resistance to generate a voltage signal with an amplitude of 1VP-P differential. The
positive and negative rails of the differential signal can be
sampled at the IOUTP and IOUTN probe connectors. The
differential signal is converted into a 50Ω singled-ended
signal with transformers T1 and T2 and can be sampled
at the OUT SMA connector. A shunt on jumper JU3 connects the center tap of the transformer T2 to AGND to
enhance the dynamic performance of the MAX5885. The
single-ended output signal from the transformer generates a -2dBm full-scale output power when terminated
into 50Ω. A shunt should always be installed across
jumper JU3 for optimum dynamic performance.
Table 2. Jumper JU1 (Power-Down)
SHUNT LOCATIONS
MAX5885 FUNCTION
1 and 2
Power-down mode
2 and 3
Normal operation
Table 3. Segment Shuffling Mode
(Jumper JU2)
SHUNT
LOCATION
SEL0 PIN
(JU2)
SEGMENTSHUFFLING
MODE
Installed
Connected to
D_VDD
Enabled
Not installed
Connected to
DGND with internal
pulldown resistor
Disabled
Power-Down
The MAX5885 can be powered down or up by reconfiguring jumper JU1. In power-down mode, the total power
dissipation of the DAC is reduced to less than 1mW.
See Table 2 for the jumper JU1 configuration.
Segment Shuffling
The segment shuffling function on the MAX5885
improves the dynamic performance at the cost of a
slight increase in the DAC’s noise floor. The MAX5885
EV kit provides jumper JU2, which allows the user to
enable and disable the segment-shuffling function. See
Table 3 to configure jumper JU2.
XOR Input
The MAX5885 provides an XOR input pin that may be
used to troubleshoot possible spurious or harmonic distortion degradation due to digital data feedthrough on
the PC board. The XOR pin can be accessed at pin 7
of header J1. Connect an external device to this pin to
assert a logic signal on the XOR pin. Refer to the XOR
Function (XOR ) section in the MAX5885 data sheet for
further details.
4
Evaluating the MAX5884 or MAX5883
The MAX5885 EV kit can be used to evaluate the
MAX5884 or MAX5883. The MAX5884 is a 14-bit and
the MAX5883 is a 12-bit DAC. Except for the input pins,
these DACs are pin-for-pin compatible with the
MAX5885. Replace the MAX5885 (U1) with the
MAX5884 or the MAX5883 and refer to the respective
data sheet to compare the differences in input pins and
how to modify the connections between the pattern
generator and the EV kit’s J1 input connector.
Board Layout
The MAX5885 EV kit is a four-layer board design optimized for high-speed signals. All high-speed signal
lines are routed through 50Ω impedance-matched
transmission lines. The length of these 50Ω transmission lines is matched to within 40 mils (1mm) to minimize layout-dependent data skew. The board layout
separates the digital, analog, and digital clock sections
of the circuit for optimum performance.
_______________________________________________________________________________________
_______________________________________________________________________________________
TP2
3
1
1
AVDD
JU4
4
CLKGND
C12
0.1µF
C20
47µF
6.3V
L2
MAX6161
U2
C24
OPEN
JU1
VCLK
C9
0.1µF
JU5
VREF
C22
1µF
C3
0.1µF
AVDD
12
11
10
8
9
7
6
5
4
3
2
1
13
REFIO
AGND
AVDD
PD
CLKGND
VCLK
CLKN
CLKP
CLKGND
VCLK
B2
48
R33
OPEN
14
47
15
DACREF
B3
R12
0Ω
J1–15
J1–26
R7
2kΩ
1%
FSADJ
R11
0Ω
J1–13
J1–28
XOR
B0
B1
R32
OPEN
C2
0.1µF
CLKGND
C8
0.1µF
VCLK
VCLK
C16
1µF
CLKGND
TP5
C21
10µF
10V
3
1
2
AVDD
R26
0Ω
R25
0Ω
C23
OPEN
R29
OPEN
R30
OPEN
R31
OPEN
C15
10µF
10V
DVDD
N.C. 8
7
N.C.
6
OUT
5
N.C.
R8
0Ω
R9
0Ω
R10
0Ω
R28
24.9Ω
C11
1%
0.1µF
R27
24.9Ω
1%
GND
N.C.
IN
N.C.
CLKGND
4
3
2
1
CLKGND
T3
6
J1–1
J1–3
J1–5
J1–7
J1–9
J1–11
CLKGND
V_CLK
C10
0.1µF
CLKGND
CLKGND
CLKGND
2
CLK
J1–40
J1–38
J1–36
J1–34
J1–32
J1–30
DGND
C14
47µF
6.3V
L1
JU3
16
B4
46
N.C.
R34
OPEN
R35
OPEN
C13
0.1µF
IOUTN
17
AGND
R13
0Ω
J1–17
J1–24
R6
SHORT
R1
49.9Ω
0.1%
B5
45
1
1
6
5
C1
OPEN
6
18
2
TP3
3
4
19
R4
OPEN
T1
DVDD
43
4
T2
3
U1
42
DGND
TP1
1
2
OUT
R5
SHORT
R37
OPEN
IOUTP
20
AGND
MAX5885
R2
49.9Ω
0.1%
IOUTP
B6
44
C7
0.1µF
R15
0Ω
DVDD
J1–21
J1–20
R3
100Ω
1%
R36
OPEN
IOUTN
R14
0Ω
J1–19
J1–22
21
AVDD
B7
41
B8
40
R39
OPEN
22
AGND
R17
0Ω
J1–25
J1–16
C4
0.1µF
R38
OPEN
AVDD
R16
0Ω
J1–23
J1–18
AVDD
B9
39
R40
OPEN
23
AVDD
R18
0Ω
J1–27
J1–14
C5
0.1µF
B10
38
R19
0Ω
J1–29
J1–12
24
N.C.
N.C.
N.C.
N.C.
N.C.
SEL0
DGND
DVDD
B15
B14
B13
B12
B11
37
AGND
R41
OPEN
25
26
27
28
29
30
32
31
33
34
35
36
R20
0Ω
J1–31
J1–10
R45
OPEN
R44
OPEN
C27
1µF
R24
0Ω
R23
0Ω
R22
0Ω
R21
0Ω
R43
OPEN
R42
OPEN
DVDD
C6
0.1µF
JU2
DVDD
TP4
C19
1µF
C26
10µF
10V
C18
10µF
10V
VREF
AVDD
L4
L3
C25
47µF
6.3V
J1–39
J1–37
J1–35
J1–33
C17
47µF
6.3V
AGND
V_REF
J1–2
J1–4
J1–6
J1–8
AGND
A_VDD
Evaluates: MAX5883/MAX5884/MAX5885
D_VDD
MAX5885 Evaluation Kit
Figure 1. MAX5885 EV Kit Schematic
5
Evaluates: MAX5883/MAX5884/MAX5885
MAX5885 Evaluation Kit
Figure 2. MAX5885 EV Kit Component Placement Guide—Component Side
6
_______________________________________________________________________________________
MAX5885 Evaluation Kit
Evaluates: MAX5883/MAX5884/MAX5885
Figure 3. MAX5885 EV Kit PC Board Layout—Component Side
_______________________________________________________________________________________
7
Evaluates: MAX5883/MAX5884/MAX5885
MAX5885 Evaluation Kit
Figure 4. MAX5885 EV Kit PC Board Layout—Ground Plane
8
_______________________________________________________________________________________
MAX5885 Evaluation Kit
Evaluates: MAX5883/MAX5884/MAX5885
Figure 5. MAX5885 EV Kit PC Board Layout—Power Plane
_______________________________________________________________________________________
9
Evaluates: MAX5885/MAX5884/MAX5883
MAX5885 Evaluation Kit
Figure 6. MAX5885 EV Kit PC Board Layout—Solder Side
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
10 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2003 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.