MAXIM MAX1002, MAX1003 Technical data

_________________________Quick Start
The MAX1002/MAX1003 EV kits are fully assembled and tested. Follow these steps to verify proper board operation. Do not turn on the power supplies until all
connections to the EV kit are completed.
1) Connect a +5V power supply to the pad marked VCC. Connect this supply’s ground to the pad marked GND.
2) Connect a +3.3V (MAX1003) or +5V (MAX1002) power supply to the pad labeled VCCO. Connect the supply ground to the pad marked OGND.
3) Connect a +4V power supply to the pad marked VTUNE. Connect the supply ground to the GND pad.
4) Remove the shunt from jumper JU5. This sets a 250mVp-p full-scale range.
_______________General Description
The MAX1002/MAX1003 evaluation kits (EV kits) simplify evaluation of the 60Msps MAX1002 and 90Msps MAX1003 dual, 6-bit analog-to-digital converters (ADCs). The kits include the basic components necessary to operate the on-chip oscillator as a voltage-controlled oscillator (VCO). Each board can also be easily modified to accommodate an external clocking source.
Connectors for power supplies, analog inputs, and digital outputs simplify connections to the device. The PC board features an optimized layout to ensure the best possible dynamic performance. The EV kits include a MAX1002 or MAX1003.
____________________________Features
5.85 Effective Number of Bits at 20MHz Analog
Input Frequency
Separate Analog and Digital Power and Ground
Connections with Optimized PC Board Layout
Matched Single-Ended or Differential Analog
Inputs for Both I and Q Channels
Square-Pin Header for Easy Connection of Logic
Analyzer to Digital Outputs
User-Selectable ADC Full-Scale Gain RangesFully Assembled and Tested
Evaluate: MAX1002/MAX1003
MAX1002/MAX1003 Evaluation Kits
________________________________________________________________
Maxim Integrated Products
1
19-1250; Rev 0; 6/97
QTY DESCRIPTION
C1, C10,
C11, C12
4
C2, C3,
C6, C7
4
C4, C15 2
0.22µF, 25V min, 10% ceramic capacitors
C5 1
C8, C9,
C13, C14
4
0.1µF, 10V min, 10% ceramic capacitors
R1 1
R2, R3 2
R4–R7 4
L1 1
220nH inductor Coilcraft 1008CS-221TKBC
MAX1003CAX, 90Msps
D1 1
Varactor diode M/A-COM MA4ST079CK-287, SOT23
IIN+, IIN-,
QIN+, QIN-
4 BNC connectors
None 1 MAX1002/MAX1003 circuit board
5pF, 10V min, 10% ceramic capacitor (MAX1003)
47pF, 25V min, 5% ceramic capacitors
0.01µF, 25V min, 10% ceramic capacitors
SUPPLIER* PHONE FAX
AVX (803) 946-0690 (803) 626-3123
______________Component Suppliers
DESIGNATION
10k, 5% resistor 47k, 5% resistors
49.9, 1% resistors
____________________Component List
______________Ordering Information
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
Coilcraft (847) 639-6400 (847) 639-1469 M/A-COM (617) 564-3100 (617) 564-3050 Sprague (603) 224-1961 (603) 224-1430
JU1, JU2,
JU6, JU7
4 0resistors
JU3, JU4,
JU8, JU9
4 2-pin headers
JU5 1 3-pin header
JU11 1 2-pin header (MAX1002 only)
J1 1 26-pin connector
None 1 Shunt for JU5
22pF, 10V min, 10% ceramic capacitor (MAX1002)
U1 1
MAX1002CAX, 60Msps
*
Please indicate that you are using the MAX1002/MAX1003 when contacting these component suppliers.
PART
MAX1002EVKIT-SO MAX1003EVKIT-SO 0°C to +70°C
0°C to +70°C
TEMP. RANGE BOARD TYPE
Surface Mount Surface Mount
C16, C17 2
10µF, 10V min, 20% tantalum caps AVX TAJC106K016
查询MAX1002EVKIT供应商
Evaluate: MAX1002/MAX1003
5) Using an RF power splitter-combiner, connect a 250mVp-p, 20MHz sine-wave source to both analog inputs at BNC J3 and J6. The analog input imped­ance is 50for each channel.
6) Connect a logic analyzer to connector J1 to monitor the digital outputs.
7) Turn on all power supplies and signal sources.
8) Observe the digitized analog input signals with the logic analyzer.
_______________Detailed Description
EV Kit Jumpers
The MAX1002/MAX1003 EV kits contain several jumpers that control board and part options. The follow­ing sections describe the different jumpers and their purposes. Table 1 lists the jumpers on the EV kits and their default positions.
Table 1. EV Kit Jumpers and Default Positions
Power Requirements
Both the MAX1002 and the MAX1003 require +5V at about 65mA for their analog VCCsupply. Power-supply requirements for the digital outputs, however, are differ­ent for the two devices. 0resistors are installed at jumper sites JU1, JU2, JU6, and JU7, and can be removed to sense device power-supply currents with an ammeter.
MAX1003 Digital Outputs Supply
The MAX1003 requires +3.3V for the V
CCO
supply. The current requirement from the power supply is a function of the sampling clock and analog input frequencies, as well as the capacitive loading on the digital outputs. With 15pF loads and a 20MHz analog input frequency sampled at 90Msps, the current draw is about 10mA.
MAX1002 Digital Outputs Supply
The MAX1002 uses +5V for its V
CCO
supply. As with the MAX1003, the current requirement is a function of the analog input frequency and capacitive loading on the outputs. With 15pF loads and a 20MHz analog input sampling at 60Msps, the current requirement is about 13mA. You can also use a single power supply for both the VCCand V
CCO
supplies by installing jumper JU11, located near the EV kit power-supply connectors. However, for best dynamic performance, use separate analog and digital power supplies.
Analog Inputs
The analog inputs to the dual ADCs are provided through BNC connectors IIN+, IIN-, QIN+, and QIN-. The connectors are terminated with 49.9to ground and are AC coupled to the converter’s analog inputs, which are internally self-biased at 2.35V DC. A typical application circuit drives the IIN+ and QIN+ noninvert­ing analog inputs using AC-coupled in-phase and quad­rature signals. The nominal 20kinput resistance of the analog inputs, plus the 0.1µF AC-coupling capacitor value, sets the low-frequency corner at about 80Hz.
You can drive the analog inputs either single-ended or differentially using AC- or DC-coupled inputs. Either the inverting or the noninverting input can be driven single­ended. If the inverting input is driven, then the digital output codes are inverted (complemented). Refer to the MAX1002 or MAX1003 data sheet for typical circuits.
ADC Gain Selection
The single GAIN-select pin on the MAX1002 or MAX1003 controls the full-scale input range for both the I and the Q channels. Jumper JU5 is used to manually select the desired gain range as shown in Table 2. The EV kits are shipped with the mid-gain range selected (jumper pins open).
Table 2. Gain-Selection Jumper JU5 Settings
MAX1002/MAX1003 Evaluation Kits
2 _______________________________________________________________________________________
Open
Offset-correction amplifier enabled
JU3, JU4,
JU8, JU9
Shorted with 0
resistors
Power-supply current­sense ports
JU1, JU2,
JU6, JU7
DEFAULT POSITION
FUNCTIONJUMPER(S)
Open
VCCO tied to VCC for single-supply operation (MAX1002)
JU11
Open
ADC full-scale range selection
JU5
Mid-gain, 250mVp-p
No pins shorted
Low-gain, 500mVp-pPins 1 and 2 shorted
ADC GAIN RANGECONNECTIONJU5 SETTING
High-gain, 125mVp-pPins 2 and 3 shorted
JU5
1 2 3
JU5
1 2 3
JU5
1 2 3
Table 3 lists the possible input-drive combinations for the mid-gain (250mVp-p) full-scale range selection. Drive levels are referenced to the open-circuit, com­mon-mode voltage of the analog inputs (typically
2.35V) if DC coupled, or to ground if AC coupling is used. If the low-gain (500mVp-p) range is selected, the input-drive requirements are twice those listed in Table
3. If the high-gain (125mVp-p) range is selected, the input-drive requirements are half those listed in Table 3.
Table 3. Typical Input-Drive Requirements for Mid-Gain
Offset-Correction Amplifiers
The offset-correction amplifiers included on the MAX1002 and MAX1003 are usually enabled in a typi­cal AC-coupled application circuit. For DC-coupled applications, the amplifiers must be disabled by installing shorting blocks on jumpers JU3, JU4 (I chan­nel); and JU8, JU9 (Q channel). These jumpers short device pins IOCC+ (pin 2), IOCC- (pin 3), QOCC- (pin
16), and QOCC+ (pin 17) to ground and disable the amplifiers. The MAX1002/MAX1003 EV kits are config­ured with the offset-correction amplifiers enabled (jumpers open) and AC-coupled analog inputs.
Voltage-Controlled-Oscillator Operation
The EV kits include a voltage-controlled-oscillator (VCO) circuit to set the analog-to-digital converter (ADC) sampling rate using an external resonant tank and a varactor diode. A voltage applied to the VTUNE pad changes the varactor diode’s capacitance to adjust the tank’s resonant frequency, which sets the oscillator’s sampling frequency. VTUNE voltage can be varied from 0V to a maximum of 8V.
The EV kits are designed so that a nominal VTUNE con­trol voltage of about 4V sets the ADC sampling rate to either 60Msps for the MAX1002 or 90Msps for the MAX1003. The VTUNE control voltage should be well filtered, as any noise on the supply contributes to jitter in the internal oscillator and degrades the converters’ dynamic performance. Figures 1 and 2 show the VTUNE control-voltage typical frequency-adjustment ranges for the MAX1002 and MAX1003 EV kits, respec­tively.
Evaluate: MAX1002/MAX1003
MAX1002/MAX1003 Evaluation Kits
_______________________________________________________________________________________ 3
INPUT DRIVE
Single-Ended
Noninverting
0
+125mV
QIN+ or IIN+
-125mV
Open Circuit
Open Circuit
QIN- or IIN-
Open Circuit
100000
111111
OUTPUT
CODE
000000
Open Circuit
Open Circuit
Open Circuit
0
+125mV
-125mV
Single-Ended
Inverting
011111
000000
111111
0
+62.5mV
-62.5mV
0
-62.5mV
+62.5mV
Differential
100000
111111
000000
Figure 1. MAX1002 Oscillator Frequency vs. VTUNE Control Voltage
60
70 65
80 75
90 85
95
105 100
110
0 2 31 4 5 6 7 8
MAX100/1003-fig2
VTUNE CONTROL VOLTAGE (V)
FREQUENCY (MHz)
Figure 2. MAX1003 Oscillator Frequency vs. VTUNE Control Voltage
70 68 66 64 62 60 58
FREQUENCY (MHz)
56 54 52 50
0 2 31 4 5 6 7 8
VTUNE CONTROL VOLTAGE (V)
MAX100/1003-fig1
Evaluate: MAX1002/MAX1003
External Clock Operation
The MAX1002/MAX1003 EV kits can be converted to drive the ADCs from an external clock source. This involves removing the external resonator components from the VCO circuit and adding a few new compo­nents. Table 4 lists the EV kit changes required to con­vert the board to accept an external clock source. The resulting schematic is shown in Figure 4.
The new 49.9value of R3 shown in Figure 4 provides proper termination for a 50external signal generator. AC-coupling capacitor C6 couples the external clock signal to the MAX1002/MAX1003 oscillator circuitry at TNK+ (pin 9). R2 and C7 ensure that the impedance at both ports of the oscillator is balanced. After all modifi­cations are complete, connect an external clock source to the BNC connector on the EV kit marked CLOCK OVERDRIVE. The recommended clock amplitude is 1Vp-p; however, the ADC operates correctly with as lit­tle as 100mVp-p or up to 2.5Vp-p on CLOCK OVER­DRIVE.
The external clock source should have low phase noise for best dynamic performance. A low-phase-noise sine-wave oscillator serves this purpose well. A square­wave clock source is not necessary to drive the MAX1002/MAX1003. The devices contain sufficient gain to amplify even a low-level-input sine wave to drive the ADC comparators, while ensuring excellent dynam­ic performance.
Digital Outputs
The TTL/CMOS-compatible digital outputs are present­ed in parallel from both I and Q channels at connector J1. The data format is offset binary with the MSB as D5 and the LSB as D0. The row of pins closest to the board edge is digital output ground (OGND), while the data bits occupy the inside row. Located in the middle of the connector is the pin for the output clock labeled DCLK. This signal can be used to latch the parallel out­put data for capture into a logic analyzer or external DSP circuitry. Both digital outputs are updated on DCLK’s rising edge (see the timing diagram in the MAX1002 or MAX1003 data sheet).
_____________Layout Considerations
The MAX1002/MAX1003 EV kit layouts have been opti­mized for high-speed signals. Careful attention has been given to grounding, power-supply bypassing, and signal-path layout to minimize coupling between the analog and digital sections of the circuit. For example, the ground plane has been removed under the tank cir­cuitry to reduce stray capacitive loading on the relative­ly small capacitors required in the external resonant tank formed by C5, L1, and D1. Other layout considera­tions are detailed in the following sections.
Power Supplies and Grounding
The EV kits feature separate analog and digital power supplies and grounds for best dynamic performance. A thin trace located on the backside of the circuit board near the VCC power-supply connector ties the analog and output ground planes together. This trace can be cut if the power-supply grounds are referenced else­where.
Referencing analog and digital grounds together at a single point usually avoids ground loops and corruption of sensitive analog circuitry by noise from the digital outputs. If the ground trace on the backside of the board is cut, observe the absolute maximum ratings between the two grounds.
MAX1002/MAX1003 Evaluation Kits
4 _______________________________________________________________________________________
5pF capacitor (MAX1003), 22pF capacitor (MAX1002)
Clock input BNC connector
DESCRIPTION
47pF capacitors
COMPONENT
Clock Overdrive
C6, C7
C5
Remove
Add
MODIFICATION
Replace with
0.01µF capaci­tors
10kresistor
220nH inductor
Remove
Remove
47kresistors
Replace with
49.9resistors
L1
R2, R3
R1
Varactor diode RemoveD1
Table 4. External Clock Source EV Kit Modifications
Bypassing
Proper bypassing is essential to achieve the best dynamic performance from the converters. The MAX1002/MAX1003 EV kits use 10µF bypass capaci­tors located close to the power-supply connectors on the board to filter low-frequency supply ripple. High-fre­quency bypassing is accomplished with ceramic chip capacitors located very close to the device’s supply pins.
As the digital outputs toggle, transient currents in the V
CCO
supply can couple into sensitive analog circuitry and severely degrade the converters’ effective number of bits performance. Of particular concern is effectively bypassing V
CCO
to OGND. For best results, locate the bypass capacitors on the same side of the board and place them close to the device. This avoids the use of through-holes and results in lower series inductance. The capacitor size chosen for the EV kits (size 0603) keeps the layout compact. Finally, the modest value (47pF) and small size result in a high self-resonant fre­quency for effective high-frequency bypassing.
__________Applications Information
To achieve the full dynamic potential from the convert­ers, minimize the capacitive loading on the digital out­puts to reduce the transient currents at V
CCO
and OGND. The maximum capacitance per output bit should be less than 15pF. For example, the capaci­tance of the digital output traces and the J1 connector on the EV kits is about 3pF per trace. In an applications circuit, this could be further reduced by locating the digital receiving chip very close to the MAX1002/ MAX1003 and removing the ground plane from under the output bit traces.
A logic analyzer can be connected to the J1 connector on the EV kits for evaluation purposes. The analyzer should be directly connected to the EV kit without any additional ribbon cables. Even a short length of ribbon cable can exceed the maximum recommended capaci­tive loading of the digital outputs. A typical high-speed logic analyzer probe adds about another 8pF loading per digital bit, which is acceptable for good dynamic performance.
Evaluate: MAX1002/MAX1003
MAX1002/MAX1003 Evaluation Kits
_______________________________________________________________________________________ 5
Evaluate: MAX1002/MAX1003
MAX1002/MAX1003 Evaluation Kits
6 _______________________________________________________________________________________
36
35
34
33
32
31
30
29
28
27
26
25
24
23
1
1 3
JU5
2
2
3
4
5
6
7
8
9
10
11
12
13
14
MAX1003
(MAX1002)
22
21
20
19
15
QIN-
V
CC
GND
GND
TNK-
TNK+
VCCGND
VCCIIN-
IIN+
IOCC-
IOCC+
GAIN
IIN+
QIN-
QIN+
BNC
BNC
R4
49.9
R5
49.9
R3
47k
C10
0.01µF
C4
0.22µF
R1
10k
D1
R2
47k
R7
49.9
R6
49.9
VTUNE
VCC
BNC
(22pF)
BNC
= ANALOG GROUND (GND)
= DIGITAL GROUND (OGND)
1
2
3
C8
0.1µF
C9
0.1µF
JU4
VCC
JU3
JU6
0
C13
0.1µF
C1
0.01µF
C3
47pF
C2
47pF
C11
0.01µF
C12
0.01µF
C14
0.1µF
C6
47pF
C7
47pF
C5
5pF
L1
220nH
VCC
JU7
0
IIN-
GND
QOCC+
QOCC-
QIN+
V
CC
DI5
DI4
DI3
DI2
DI1
DQ2
DI0
DCLK
V
CC
OGND
V
CC
DQ0
DQ1
GND
DQ3
DQ4
DQ5
J1–1
J1–3
J1–5
J1–7
J1–9
J1–11
J1–13
JU2
0
JU1
0
VCC
VCCO
J1–15
J1–17
J1–19
J1–21
J1–23
J1–25
J1–4
J1–6
J1–8
J1–10
J1–12
J1–2
J1–16
J1–18
J1–20
J1–22
J1–24
J1–26
J1–14
U1
16
17
18
VTUNE VTUNE
= MAX1002
C16
10µF
VCC
VCCO
JU11
CUT HERE
TO SEPARATE
GROUNDS
JU9
JU8
VCC
GND
VCCO
C15
0.22µF
C17
10µF
OGND
( )
Figure 3. MAX1002/MAX1003 EV Kit Schematic (Voltage-Controlled-Oscillator Mode)
Evaluate: MAX1002/MAX1003
MAX1002/MAX1003 Evaluation Kits
_______________________________________________________________________________________ 7
36
35
34
33
32
31
30
29
28
27
26
25
24
23
1
1 3
JU5
2
2
3
4
5
6
7
8
9
10
11
12
13
14
MAX1003
(MAX1002)
22
21
20
19
15
QIN-
V
CC
GND
GND
TNK-
TNK+
VCCGND
VCCIIN-
IIN+
IOCC-
IOCC+
GAIN
VCC
IIN+
QIN-
QIN+
BNC
BNC
R4
49.9
R5
49.9
C10
0.01µF
C4
0.22µF
R6
49.9
VCC
BNC
BNC
C8
0.1µF
C9
0.1µF C6
0.01µF
C7
0.01µF
JU4
JU3
0
JU6
C13
0.1µF
C1
0.01µF
C3
47pF
C2
47pF
C11
0.01µF
C12
0.01µF
C14
0.1µF
VCC
JU7
0
IIN-
GND
QOCC+
QOCC-
QIN+
V
CC
DI5
DI4
DI3
DI2
DI1
DQ2
DI0
DCLK
V
CC
OGND
V
CC
DQ0
DQ1
GND
DQ3
DQ4
DQ5
R7
49.9
J1–1
J1–3
J1–5
J1–7
J1–9
J1–11
J1–13
JU2
0
JU1
0
VCC
VCCO
J1–15
J1–17
J1–19
J1–21
J1–23
J1–25
J1–4
J1–6
J1–8
J1–10
J1–12
J1–2
J1–16
J1–18
J1–20
J1–22
J1–24
J1–26
J1–14
BNC
CLK_IN
R3
49.9
R2
49.9 = ANALOG GROUND
= DIGITAL GROUND
U1
16
17
18
VTUNE VTUNE
= MAX1002
C16
10µF
VCC
VCCO
JU11
CUT HERE
TO SEPARATE
GROUNDS
JU9
JU8
VCC
GND
VCCO
C15
0.22µF
OGND
C17
10µF
( )
Figure 4. MAX1002/MAX1003 EV Kit Schematic (External Clock Operation)
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.
8
___________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1997 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Evaluate: MAX1002/MAX1003
MAX1002/MAX1003 Evaluation Kits
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.
8
___________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1997 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Figure 5. MAX1002/MAX1003 EV Kit Component Placement Guide—Component Side
Figure 6. MAX1002/MAX1003 EV Kit Component Placement Guide—Solder Side
Figure 7. MAX1002/MAX1003 EV Kit PC Board Layout— Component Side
Figure 8. MAX1002/MAX1003 EV Kit PC Board Layout— Solder Side
1.0"
1.0"
1.0"
1.0"
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