MAXIM MAX1448EVKIT

19-1799; Rev 1; 7/01
MAX1448 Evaluation Kit
Features
♦ Up to 80Msps Sampling Rate
♦ Low-Voltage, Low-Power Operation
♦ Single-Ended or Fully Differential Signal Input
Configuration
♦ Clock-Shaping Circuit
♦ Fully Assembled and Tested
Ordering Information
PART
TEMP. RANGE
MAX1448EVKIT
0°C to +70°C
IC PACKAGE
32 TQFP
Component List
DESIGNATION
QTY
C1, C2, C4–C8,
C10,C16–C20,
C22, C27,
C33–C39
22
C3, C9
2
C11, C21, C24,
C26, C28, C29,
C31, C32
8
C12–C15
4
DESCRIPTION
DESIGNATION
QTY
0.1µF, 50V X7R ceramic
capacitors (0805)
Taiyo Yuden UMK212BJ104KG or
equivalent
R4, R5, R38
3
R8, R24–R33
11
100Ω ±1% resistors (0805)
R9, R10, R36
3
2kΩ ±1% resistors (0805)
R11
1
6.04kΩ ±1% resistor (0805)
R12, R37
2
4.02kΩ ±1% resistors (0805)
R40
1
10kΩ ±1% resistor (0805)
R41
1
3.9Ω ±5% resistor (0805)
2.2µF,10V tantalum capacitors (A)
AVX TAJA225K010 or
Kemet T494A225K010AS
R34
1
5kΩ potentiometer
T1
1
RF transformer
Mini-Circuits TT1-6-KK81
10µF, 10V tantalum capacitors (B)
AVX TAJB106M010 or
Kemet T494B106K010AS
U1
1
MAX1448EHJ (32-pin TQFP)
U2
1
Dual CMOS differential line
receiver (8-pin SO)
Maxim MAX9113ESA
U3
1
Buffer/driver 3-state output
(48-pin TSSOP)
Texas Instruments
SN74ALVCH16244DGG or
Pericom PI74ALVCH16244A
SINGLE, DIFF,
CLOCK
3
SMA PC-mount connectors
None
4
Shunts (JU1 to JU4)
None
1
MAX1448 PC board
None
1
MAX1448 data sheet
None
1
MAX1448 EV kit data sheet
22pF, 200V ceramic capacitors
(0805)
Murata GRM2195C2D220JV01
C23, C30
0
Not installed (0805)
C25
1
1000pF, 50V COG ceramic
capacitor (0805)
Murata GRM2195C1H102JA01
J1
1
2 × 20-pin header
JU1, JU2
2
2-pin headers
JU3, JU4
2
3-pin headers
2
Ferrite chip beads (1206)
Fair-Rite Products Corp.
2512069007Y0 or
HiQ Magnetics 436-2600
L1, L2
DESCRIPTION
24.9Ω ±1% resistors (0805)
R1, R39
0
Not installed (0805)
R2, R3,
R13–R23, R35
14
49.9Ω ±1% resistors (0805)
________________________________________________________________ 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: MAX1444/MAX1446/MAX1448/MAX1449
General Description
The MAX1448 evaluation kit (EV kit) is a fully assembled
and tested circuit board that contains all the components
necessary to evaluate the performance of the MAX1444,
MAX1446, MAX1448, or MAX1449 10-bit analog-to-digital
converters (ADCs). The MAX1444/MAX1446/MAX1448/
MAX1449 ADCs process differential or single-ended analog inputs. The EV kit allows the user to evaluate the
ADCs with both types of signals from one single-ended
analog signal. The digital output produced by the ADCs
can be easily sampled with a user-provided high-speed
logic analyzer or data-acquisition system. The EV kit
comes with the MAX1448 installed. Order free samples of
the MAX1444EHJ, MAX1446EHJ or MAX1449EHJ to evaluate these parts. The EV kit operates from a +3V power
supply. It includes circuitry that generates a clock signal
from an AC signal provided by the user.
Evaluates: MAX1444/MAX1446/MAX1448/MAX1449
MAX1448 Evaluation Kit
Part Selection Table
PART
SPEED (Msps)
MAX1444EHJ
40
MAX1446EHJ
60
MAX1448EHJ
80
MAX1449EHJ
105
3)
4)
5)
Component Suppliers
SUPPLIER
PHONE
FAX
AVX
843-448-9411
843-448-1943
Fair-Rite Products
888-324-7748
888-337-7483
Kemet
864-963-6300
864-963-6322
Mini-Circuits
718-934-4500
718-934-7092
Murata
770-436-1300
770-436-3030
Pericom
800-435-2336
408-435-1100
Taiyo Yuden
800-348-2496
847-925-0899
Texas Instruments
972-644-5580
214-480-7800
Note: Please indicate that you are using the MAX1448,
MAX1444, MAX1446, or MAX1449 when contacting these
component suppliers.
Quick Start
• DC power supplies:
Digital = +3V, 100mA
Required Equipment
Analog = +3V, 100mA
• A function generator with low phase noise and low jitter for clock input (e.g., HP 8662A)
• A function generator for analog signal input (e.g.,
HP 8662A)
• A logic analyzer or data-acquisition system (e.g.,
HP 1663EP, HP 16500C)
• An analog bandpass filter (e.g., TTE elliptical function bandpass filter Q56 series)
• A digital voltmeter
The MAX1448 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
function generators until all connections are completed.
1) Connect one +3V power supply to VAIN1 and
VAIN2. Connect the ground terminal of this supply
to AGND.
2) Connect one +3V power supply to VDIN1 and
2
6)
7)
8)
9)
VDIN2. Connect the ground terminal of this supply
to DGND.
Verify that shunts are not installed in jumpers JU1
(MAX1448 enabled) and JU2 (MAX1448 output
enabled).
Connect the clock function generator to the CLOCK
SMA connector.
Connect the output of the analog signal function
generator to the input of the bandpass filter.
To evaluate differential analog signals, verify that
shunts are installed on pins 1 and 2 of jumpers JU3
and JU4. Connect the output of the bandpass filter
to the DIFF SMA connector. For single-ended analog signal evaluation, verify that shunts are installed
on pins 2 and 3 of jumpers JU3 and JU4, and connect the output of the bandpass filter to the SINGLE
SMA connector.
Connect the logic analyzer to the square pin header
(J1).
Turn on both power supplies.
With a voltmeter, verify that +1.20V is measured
across test points TP4 and TP5. If the voltage is not
+1.20V, adjust potentiometer R34 until +1.20V is
obtained.
10) Enable the function generators. Set the clock function generator to 2.4VP-P and frequency (fCLK) ≤
80MHz. Set the analog signal function generator to
2VP-P and desired frequency. The two function generators should be phase locked to each other.
11) Set the logic analyzer to latch data on the clock’s
rising edge.
12) Enable the logic analyzer.
13) Collect data using the logic analyzer.
Detailed Description
The MAX1448 EV kit is a fully assembled and tested circuit board that contains all the components necessary
to evaluate the performance of the MAX1449, MAX1448,
MAX1446, or MAX1444 10-bit ADC at a maximum clock
frequency (fCLK) of 80MHz. These ADCs can process
differential or single-ended analog inputs. With the proper board configuration, the user can evaluate the ADC
with both types of signals by supplying only one singleended analog signal to the EV kit.
The EV kit’s PC board is designed as a four-layer board
to optimize the performance of the MAX1448. Separate
analog and digital power planes minimize noise coupling between analog and digital signals. For simple
operation, the EV kit is specified to have +3V power
_______________________________________________________________________________________
MAX1448 Evaluation Kit
Power Supplies
The MAX1448 EV kit requires separate analog and digital power supplies for best performance. A +3V power
supply is used to power the analog portion of the
MAX1449/MAX1448/MAX1446/MAX1444 ADC and
the clock signal circuit. The MAX1449/MAX1448/
MAX1446/MAX1444 analog supply voltage has a range
of +2.7V to +3.3V; however, +3V must be supplied to
the EV kit (VAIN1, VAIN2) to meet the minimum input
voltage supply to the clock signal generator. A separate
+3.0V power supply is used to power the digital portion
(VDIN1, VDIN2) of the MAX1448 ADC and the buffer/driver, but it will operate with a voltage supply as low as
+1.7V and as high as +3.3V. Enhanced dynamic performance can be achieved when the digital supply voltage
is lower than the analog supply voltage.
Clock
An on-board clock-shaping circuit generates a clock signal from an AC sine-wave signal applied to the CLOCK
SMA connector. The signal should not exceed 2.6VP-P.
The typical clock frequency should be 80MHz or less.
The frequency of the sinusoidal input signal determines
the sampling frequency of the ADC. A DS90LV028A differential line receiver processes the input signal to produce the CMOS clock signal. The signal’s duty cycle can
be adjusted with potentiometer R34. A clock signal with a
50% duty cycle can be achieved by adjusting R34 until
+1.2V is produced across test points TP4 and TP5 at +3V
analog voltage supply (40% of the analog power supply).
Input Signal
The MAX1448 ADC is able to process differential or single-ended analog input signals. The EV kit requires only
one single-ended analog input signal provided by the
user. During single-ended signal operation, the signal is
applied directly to the ADC, and in differential signal
operation, an on-board transformer takes the singleended analog signal and generates a differential analog
signal at the ADC’s differential input pins. For singleended or differential signal board operation, see Table 1
for jumper configuration.
Note: When a differential signal is applied to the ADC,
its positive and negative input pins each receive half of
the input signal supplied at SMA connector DIFF centered at (VAIN1) / 2.
MAX1448 Enable/Shutdown
The MAX1448 EV kit features jumpers to enable and disable the MAX1448 (JU1) or its digital outputs (JU2). See
Table 1 for jumper settings.
External Voltage Reference
The MAX1448 ADC requires an input voltage reference
at pin 31 (REFIN) to set the full-scale analog signal voltage input. The ADC also has a stable on-chip voltage
reference of +2.048V that can be accessed at REFOUT.
The EV kit was designed to use the on-chip voltage reference by connecting REFIN to REFOUT through resistor R40. The user can externally adjust the reference
level, and hence the full-scale range, by installing a
resistor at R39. The adjusted reference level can be calculated by applying the following equation;
VREFIN = (R39 / (R40 + R39)) x VREFOUT
where R39 is the value of the resistor installed, R40 is a
10kΩ resistor, and VREFOUT is +2.048V. Alternatively,
the user can also apply a stable, low-noise, external reference voltage directly at the REFIN pad to set the full
scale.
Table 1. MAX1448 EV Kit Jumper Selection
JUMPER
JU1
JU2
SHUNT STATUS
CLOSED
OPEN
CLOSED
PIN CONNECTION
EV KIT OPERATION
PD connected to VDDUT
MAX1448 is disabled (powered down)
PD connected internally to GND
MAX1448 is enabled
OE connected to VDDUT
MAX1448 digital outputs are disabled
OE connected internally to GND
MAX1448 digital outputs are enabled
1 and 2
IN+ and IN- pins connected to SMA
connector DIFF
Analog input signal is coupled into the
ADC as a differential input
2 and 3
IN+ pin connected to SMA connector
SINGLE and IN- pin connected to COM
pin
Analog input signal is coupled into the
ADC as a single-ended input
OPEN
JU3, JU4
_______________________________________________________________________________________
3
Evaluates: MAX1444/MAX1446/MAX1448/MAX1449
supplies applied to analog and digital power planes.
However, the digital supply can be operated down to
+1.7V without compromising the board’s performance.
The logic analyzer’s threshold should be adjusted
accordingly.
Access to the output is provided through connector J1.
The 40-pin connector can easily interface directly to a
user-provided logic analyzer or data-acquisition system.
Figure 1. MAX1448 EV Kit Schematic
_______________________________________________________________________________________
TP5
R36
2kΩ
CLOCK
R34 3
5kΩ 2
1
C22
0.1µF
R35
49.9Ω
C4
0.1µF
TP4
4
3
6
5
T1
R1
OPEN
2
1
R37
4.02kΩ
R3
49.9Ω
C2
0.1µF
R2
49.9Ω
C1
0.1µF
R12
4.02kΩ
R11
6.04kΩ
R4
24.9Ω
R5
24.9Ω
3
2
4
1
C25
1000pF
VADUT
R38
24.9Ω
RIN2+
RIN1+
RIN2-
GND
ROUT2
ROUT1
VCC
U2
MAX9113
RIN1-
C32
2.2µF
10V
1
3
JU4 2
1
3
JU3 2
C10
0.1µF
R10
2kΩ
R9
2kΩ
5
6
7
8
R8, 100Ω
C33
0.1µF
C3
22pF
C9
22pF
C28
2.2µF
10V
C27
0.1µF
C6
0.1µF
C5
0.1µF
C26
2.2µF
10V
C29
2.2µF
10V
C7
0.1µF
R39
OPEN
C24
2.2µF
10V
C14
DGND 10µF
10V
C13
VDIN2 10µF
10V
VDIN1
TP3
TP2
TP1
NOTE: ALL RESISTORS ARE 0805 1% UNLESS OTHERWISE NOTED.
VA
DIFF
SINGLE
C23
OPEN
GND
IN-
IN+
GND
GND
VDD
COM
REFN
C18
0.1µF
C19
0.1µF
C11
2.2µF
10V
8
7
6
5
4
3
2
1
C8
0.1µF
R40
10kΩ
9
REFIN
32
REFP
VDD
31
REFIN
VDD
30
VDDUT
VD
C38
0.1µF
10
U1
28
29
MAX1448
GND
GND
11
REFOUT
R41
3.9Ω
JU1
CLK
12
27
D4
D8
D7
D6
D5
OVDD
T.P.
OGND
VA
VADUT
JU2
D0
PD
13
25
D3
D9
26
D1
GND
14
D2
OE
15
4
16
17
18
19
20
21
22
23
24
VDDUT
OVDD
OVDD
C12
10µF
10V
C15
10µF
10V
DGND
VDIN1
C20
0.1µF
C16
0.1µF VDIN2
C17
0.1µF
C30
OPEN
C35
0.1µF
R24, 100Ω
R25, 100Ω
R26, 100Ω
R27, 100Ω
R28, 100Ω
R29, 100Ω
C34
0.1µF
R30, 100Ω
R31, 100Ω
R32, 100Ω
R33, 100Ω
C31
2.2µF
10V
C39
0.1µF
1A1
1A2
GND
1A3
1A4
VCC
2A1
2A2
GND
2A3
2A4
3A1
3A2
GND
3A3
3A4
VCC
4A1
4A2
GND
4A3
4A4
3DE
48 2DE
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
VD
L2
13
14
15
16
17
18
19
20
21
22
23
24
1DE
1Y1
1Y2
GND
1Y3
1Y4
VCC
2Y1
2Y2
GND
2Y3
1
2
3
4
5
6
7
8
9
10
11
2Y4 12
3Y1
3Y2
GND
3Y3
3Y4
VCC
4Y1
4Y2
GND
4Y3
4Y4
4DE
U3
SN74ALVCH16244
L1
C21
2.2µF
10V
C36
0.1µF
VDDUT
R13, 49.9Ω
C37
0.1µF
R15, 49.9Ω
R17, 49.9Ω
R19, 49.9Ω
R21, 49.9Ω
R14, 49.9Ω
R16, 49.9Ω
R18, 49.9Ω
R20, 49.9Ω
R22, 49.9Ω
R23, 49.9Ω
J1-21
J1-19
J1-17
J1-15
J1-13
J1-11
J1-9
J1-7
J1-5
J1-3
J1-1
J1-40
J1-39
J1-37
J1-38
J1-35
J1-36
J1-33
J1-34
J1-32
J1-31
J1-30
J1-28
J1-29
J1-27
J1-26
J1-25
J1-24
J1-23
J1-22
J1-20
J1-18
J1-16
J1-14
J1-12
J1-10
J1-8
J1-6
J1-4
J1-2
Evaluates: MAX1444/MAX1446/MAX1448/MAX1449
MAX1448 Evaluation Kit
MAX1448 Evaluation Kit
1.0"
without compromising the digital output signal. The outputs of the buffer are connected to a 40-pin header (J1)
located on the right side of the EV kit where the user can
connect a logic analyzer or data-acquisition system.
1.0"
Figure 2. MAX1448EV Kit Component Placement Guide—
Component Side
1.0"
Figure 3. MAX1448EV Kit PC Board Layout—Component Side
1.0"
Figure 4. MAX1448EV Kit PC Board Layout—Solder Side
Figure 5. MAX1448EV Kit Component Placement Guide—
Solder Side
_______________________________________________________________________________________
5
Evaluates: MAX1444/MAX1446/MAX1448/MAX1449
Output Buffer/Driver
The SN74ALVCH16244 buffer/driver buffers the
MAX1448’s digital output, which produces straight offset
binary data. The buffer is able to drive capacitive loads,
which may be present at the logic analyzer connection,
Evaluates: MAX1444/MAX1446/MAX1448/MAX1449
MAX1448 Evaluation Kit
1.0"
1.0"
Figure 6. MAX1448EV Kit PC Layout—Ground Planes
Figure 7. MAX1448EV Kit PC Layout—Power Planes
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.
6 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2001 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.