MAXIM MAX3822EVKIT

19-2144; Rev 0; 8/01
MAX3822 Evaluation Kit
Features
♦ Fully Assembled and Tested
♦ Easy Loss-of-Power (LOP) Threshold
Programming
♦ LOP Indicators
♦ Channel-Select Configuration Pins
Ordering Information
Component List
DESIGNATION
QTY
DESCRIPTION
19
0.1µF ±10% 10V ceramic
capacitors
C17–C20
4
0.033µF ±10% 10V ceramic
capacitors
C26
1
33µF tantalum capacitor
C27
1
2.2µF ±10% 10V ceramic
capacitor
C1–C16, 21, 25,
28
J1–J8, J10–J17
16
SMA connectors (edge mount)
EFJohnson 142-0701-801
J9, J18–J22
6
3-pin headers (0.1in centers)
J23, J24
2
Shunts
J23, J24
2
2-pin headers (0.1in centers)
L1, L2
2
56nH SMD inductors
LED1–LED5
5
Red T1 packages
R1–R5
5
150Ω ±1% resistors
R6
1
100Ω ±1% resistor
R7
1
1kΩ potentiometer
PART
MAX3822EVKIT
TEMP. RANGE
0°C to +85°C
IC PACKAGE
48 TQFP
*Exposed pad
Component Suppliers
SUPPLIER
PHONE
FAX
Coilcraft
847-639-6400
847-639-1469
Sprague
207-324-4140
603-224-1430
Note: Please indicate that you are using the MAX3822 EV kit
when contacting these component suppliers.
Quick Start
1) Set the channel-select (CS) pin to enable channel
1 by removing the shunt from J9.
2) Set the threshold level to mid-range by adjusting
threshold control potentiometers R7 and R8 for
650Ω measured between VTH and ground.
R8
1
200Ω potentiometer
U1
1
MAX3822ECM 48-pin TQFP
3) Enable the LOP and LOP1 indicators by placing
shunts across the LED side of J22 and J18.
VCC, GND
2
Test points
4) Ensure shunts on J23 and J24 are in place.
None
1
MAX3822 evaluation circuit
board, Rev C
5) Connect ground and a +3.3V supply to the proper
terminals on the EV kit.
None
1
MAX3822 data sheet
None
1
MAX3822 EV kit data sheet
6) Connect the inputs of channel 1 to a 50Ω source
using 50Ω SMA cables. Set the source to produce
a differential 50mVp-p 2.5Gbps signal.
7) Connect the outputs of channel 1 to a 50Ω oscilloscope with 50Ω SMA cables.
8) Power up the EV kit.
9) Check that the amplified and limited input pattern
is present on the output.
________________________________________________________________ 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: MAX3822
General Description
The MAX3822 evaluation kit (EV kit) is a fully assembled
demonstration board that simplifies evaluation of the
MAX3822 quad limiting amplifier. The EV kit is shipped
from the factory with all components needed to interface with standard 50Ω test equipment. The kit features
on-board power-supply filtering and consumes approximately 240mA with a +3.3V supply. To facilitate evaluation of the MAX3822 at speed, the EV kit is laid out with
50Ω controlled impedance on all signal lines.
Evaluates: MAX3822
MAX3822 Evaluation Kit
Detailed Description
The MAX3822 EV kit contains all components necessary to evaluate the MAX3822 quad-limiting amplifier.
The completely assembled and factory-tested EV kit
features on-board power-supply filtering and operates
from a single +3.3V supply. In quad-channel operation,
the MAX3822 EV kit consumes approximately 240mA
(current consumption drops to approximately 70mA for
single-channel operation). The MAX3822 EV kit is
shipped from the factory configured for interfacing with
standard 50Ω test equipment.
Side-mount SMA connectors are used for the
MAX3822’s signal I/O ports. To simplify interfacing to
50Ω test equipment, the EV kit provides AC-coupling
for the MAX3822’s CML inputs and outputs. All differential input and output data paths are 50Ω controlledimpedance transmission lines.
The MAX3822 EV kit facilitates programming of the
input signal level threshold with two potentiometers.
Use R7 for coarse tuning and R8 for fine tuning. Test
points and LEDs are provided for monitoring the
MAX3822’s LOP output. The LOP outputs are connected to the two pins on the OUT side of J18–J22.
Program the MAX3822’s operational mode with J9.
Single-, dual-, and quad-channel operation is accom-
plished by shunting (or removing the shunt from) the
appropriate pins of J9. For single-channel operation,
remove the shunt from J9 to enable channel 1. For
dual-channel operation, shunt pins 1 and 2 on J9 to
enable channels 1 and 2. For quad-channel operation,
shunt pins 2 and 3 on J9 to enable all four channels.
When in single- or dual-channel operation, the unused
amplifiers are shut down and overall current consumption is reduced. If desired, current consumption can be
further reduced by disabling the LOP diodes’ drive current. Current is delivered to the LEDs through J18–J22.
For example, to conserve current while in dual-channel
operation, disable LEDs for channels 1 and 2 by removing the shunts from J18 and J19.
Connections, Adjustments,
and Controls
Layout Considerations
The MAX3822 quad limiting amplifier is a high-gain,
high-frequency device whose performance can be
affected by poor board layout. The MAX3822 EV kit is
fabricated on a four-layer board with controlled impedance transmission lines and separate power and
ground planes. Supply noise filtering is done with
inductive filtering and decoupling capacitors placed
close to the IC’s VCC pins.
Table 1. Jumpers, Test Points, and Indicators
2
NAME
TYPE
FUNCTION
J9
3-pin header
Channel-Select Input. Leave all pins open to enable channel 1. Short pins 1 and 2 to
activate channels 1 and 2. Short pins 2 and 3 to enable all four channels.
J18
3-pin header
Connects LOP LED Indicator to the LOP Output of Channel 1. Shunting pins on the LED
side causes the LOP output to be connected to the LED and removing the shunt opens the
LOP LED.
J19
3-pin header
Connects LOP LED Indicator to the LOP Output of Channel 2. Shunting pins on the LED
side causes the LOP output to be connected to the LED and removing the shunt opens the
LOP LED.
J20
3-pin header
Connects LOP LED Indicator to the LOP Output of Channel 3. Shunting pins on the LED
side causes the LOP output to be connected to the LED and removing the shunt opens the
LOP LED.
_______________________________________________________________________________________
MAX3822 Evaluation Kit
Evaluates: MAX3822
Table 1. Jumpers, Test Points, and Indicators (continued)
NAME
TYPE
FUNCTION
J21
3-pin header
Connects LOP LED Indicator to the LOP Output of Channel 4. Shunting pins on the LED
side causes the LOP output to be connected to the LED and removing the shunt opens the
LOP LED.
J22
3-pin header
Connects the General LOP LED Indicator to the General LOP Output of Quad Limiting
Amplifier. Shunting on the LED side causes the LOP output to be connected to the LED
and removing the shunt opens the LOP LED.
J23
2-pin header
Jumper from Power Supply to the Device VCC
J24
2-pin header
Jumper from Power Supply to the LEDs
LED1
LED
LOP Indicator for Channel 1. Lights when limiting amplifier 1 is in the LOP state.
LED2
LED
LOP Indicator for Channel 2. Lights when limiting amplifier 2 is in the LOP state.
LED3
LED
LOP Indicator for Channel 3. Lights when limiting amplifier 3 is in the LOP state.
LOP Indicator for Channel 4. Lights when limiting amplifier 4 is in the LOP state.
LED4
LED
LOP LED5
LED
VCC
Test point
General LOP Indicator. Lights when any of the four limiting amplifiers is in the LOP state.
Power-Supply Connection
GND
Test point
R7
Potentiometer
Coarse Power-Detection Threshold Adjustment
Ground Connection
R8
Potentiometer
Fine Power-Detection Threshold Adjustment
_______________________________________________________________________________________
3
Evaluates: MAX3822
MAX3822 Evaluation Kit
3
C17
0.033µF
R8
200Ω
1
J9
2
P7
J5
C5
0.1µF
P8
P9
P10
C6
0.1µF
P11
J6
J7
C7
0.1µF
J8
C8
0.1µF
P12
VCC
IN2+
IN2-
VTH
GND
OUT2+
OUT2-
U1
VCC
VCC
IN3+
IN3-
VCC
VCC
OUT3+
OUT3-
MAX3822
VCC
VCC
IN4+
IN4-
OUT4+
OUT4-
C19
0.033µF
C20
0.033µF
J23
L2
56nH
J24
C9
0.1µF
J10
C10
0.1µF
J11
P34
P33
C11
0.1µF
J12
P32
P31
C12
0.1µF
P30
P29
P28
P27
P26
J13
C13
0.1µF
J14
P25
C14
0.1µF
J15
C15
0.1µF
J16
C16
0.1µF
J21
R4
150Ω
J17
LED4
J20
R3
150Ω
LED3
J19
R2
150Ω
LED2
J18
R1
150Ω
LED1
J22
R5
150Ω
LED5
Figure1. MAX3822 EV Kit Schematic
4
C26
33µF
L1
56nH
P40
P39
P38
P37
OUT1VCC
LOP3
LOP4
P6
GND
GND
P42
P41
P48
P47
P46
P45
P44
P43
P5
OUT1+
P36
P35
P24
C4
0.1µF
P3
P4
C27
2.2µF
R7
1kΩ
IN1+
IN1-
LOP1
LOP2
J4
C3
0.1µF
P1
P2
P22
P23
J3
GND
CZ1+
CZ1GND
CZ2+
CZ2GND
CS
C2
0.1µF
GND
CZ4CZ4+
GND
CZ3CZ3+
GND
LOP
J2
P13
P14
P15
P16
P17
P18
P19
P20
P21
C1
0.1µF
C25
C21
C28
0.1µF 0.1µF 0.1µF
3
C18
0.033µF
1
J1
GND
R6
100Ω
2
_______________________________________________________________________________________
VCC
MAX3822 Evaluation Kit
Evaluates: MAX3822
1.0"
1.0"
Figure 2. MAX3822 EV Kit Component Placement Guide—
Component Side
1.0"
Figure 3. MAX3822 EV Kit PC Board Layout—Component Side
1.0"
Figure 4. MAX3822 EV Kit PC Board Layout—Ground Plane
Figure 5. MAX3822 EV Kit PC Board Layout—Power Plane
_______________________________________________________________________________________
5
Evaluates: MAX3822
MAX3822 Evaluation Kit
1.0"
Figure 6. MAX3822 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.
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.