View MAX3850EVKIT_324137.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

19-2363; Rev 0; 4/02
MAX3850 Evaluation Kit
General Description
The MAX3850 evaluation kit (EV kit) is an assembled demonstration board that provides optical or electrical evaluation of the MAX3850. The EV kit is composed of two independent electrically isolated sections on the PC board. The output of the electrical evaluation section is interfaced to an SMA connector, which can be connected to a 50 terminated oscilloscope. The output of the optical evaluation section is configured for attachment to a laser/monitor diode. o Fully Assembled and Tested o +3.3V Operation o Input Termination Provided On-Board o Independent Electrical Monitoring of Modulation and Bias Currents o Supports Optical and Electrical Evaluation
Features
Evaluates: MAX3850
Component Suppliers
SUPPLIER AVX Coilcraft Murata Zetex PHONE 843-444-2863 847-639-6400 814-237-1431 516-543-7100 FAX 803-626-3123 847-639-1469 814-238-0490 516-864-7630 PART MAX3850EVKIT
Ordering Information
TEMP RANGE -40C to +85C IC PACKAGE 32 QFN
Note: Please indicate that you are using the MAX3850 when ordering from these suppliers.
Electrical Component List
DESIGNATION C7 C8 C24, C25, C28, C32 C26, C27, C29, C30, C33 C40 C41, C45 C42 C43 D3 J5-J9 JU4, JU5 JU4, JU5 L9 Q2 QTY 1 1 4 5 1 2 1 1 1 5 2 2 1 1 DESCRIPTION 0.5pF 0.1pF, 10V min, ceramic capacitor (0402) 1.0pF 0.1pF, 10V min, ceramic capacitor (0402) 0.01F 10%, 10V min, ceramic capacitors (0402) 0.1F 10%, 10V min, ceramic capacitors (0402) 10F 20%, 10V min, tantalum capacitor (case B) 0.01F 10%, 10V min, ceramic capacitors (0603) 0.1F 10%, 10V min, ceramic capacitor (0603) 1000pF 10%, 10V min, ceramic capacitor (0402) LED red T1 pkg Digi-Key P363-ND SMA connectors, edge mount 1 x 2-pin headers, 0.1in centers Shunts Digi-Key 220nH inductor Coilcraft 1008HS-221TKBC FMMT591A SOT-23 Zetex "91A" marking DESIGNATION R4, R17, R44 R5, R22 R6 R23 R28, R32 R34 R37, R43 R38 R40 R41 R42 R46 R47 R49 TP2, TP3, TP8, TP10-TP13, TP17, TP18, TP21, TP22 U2 U3 QTY 3 2 1 1 2 1 2 1 1 1 1 1 1 1 11 1 1 DESCRIPTION 30.1 1% resistors (0402) 1.5k 1% resistors (0402) DO NOT INSTALL (0603) 1k 1% resistor (0402) 100 1% resistors (0402) 110 1% resistor (0603) 392 1% resistors (0402) 49.9 1% resistor (0402) 100k variable resistor Bourns 3296W-104-ND Digi-Key 50k variable resistor Bourns 3296W-104-ND Digi-Key 200k variable resistor Bourns 3296W-104-ND Digi-Key 15 1% resistor (0603) 1.5k 1% resistor (0603) 75 1% resistor (0402) Test points MAX3850EGJ 32 QFN MAX495ESA 8-pin SO
________________________________________________________________ Maxim Integrated Products
1
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.
MAX3850 Evaluation Kit Evaluates: MAX3850
Optical Component List
DESIGNATION QTY C1-C4, C17, C38 C5, C10-C13 C6 C16 C19 C20, C22, C36 C35 D1 J1-J4 JU1, JU2 JU1, JU2 L2 L4 6 5 1 1 1 3 1 1 4 2 2 1 1 DESCRIPTION 0.01F 10%, 10V min, ceramic capacitors (0402) 0.1F 10%, 10V min, ceramic capacitors (0402) 1000pF 10%, 10V min, ceramic capacitor (0402) 0.1F 10%, 10V min, ceramic capacitor (0603) 10F 20%, 10V min, tantalum capacitor (Case B) 0.01F 10%, 10V min, ceramic capacitors (0603) 8.2pF 10%, 10V min, ceramic capacitor (0402) LED red T1 pkg Digi-Key 363-ND SMA connectors, edge mount 1 x 2-pin headers, 0.1in centers Shunts Digi-Key Ferrrite bead Murata BLM18HG601SN1 220nH inductor Coilcraft 1008HS-221TKBC DESIGNATION QTY R1, R2 R3 R8, R12 R14 R15 R16 R18 R19, R35 R20 R21, R36 R27 TP1, TP4, TP5, TP6, TP14, TP15, TP16, TP19, TP20 U1 U4 None None None 2 1 2 1 1 1 1 2 1 2 1 DESCRIPTION 1.5k 1% resistors (0402) 1k 1% resistor (0402) 100 1% resistors (0402) 50k variable resistor Bourns 3296W-503-ND Digi-Key 200k variable resistor Bourns 3296W-503-ND Digi-Key 100k variable resistor Bourns 3296W-503-ND Digi-Key 110 1% resistor (0603) 392 1% resistors (0402) 11 1% resistor (0402) 49.9 1% resistors (0402) 16.2 1% resistor (0402)
9
Test points
1 1 1 1 1
MAX3850EGJ 32-pin QFN User-supplied laser diode MAX3850 data sheet MAX3850 EV kit circuit board, rev B MAX3850 EV kit data sheet
Quick Start
Electrical Evaluation
In the electrical configuration, an automatic power control (APC) test circuit is included to emulate a semiconductor laser with a monitor photodiode. Monitor diode current is provided by Q2, which is controlled by an operational amplifier (U3). The APC test circuit, consisting of U3 and Q2, applies the simulated monitor diode current (the laser bias current divided by a factor of 100) to the MD pin of the MAX3850. To ensure proper operation of the electrical configuration, set up the evaluation board as follows: 1) If data is to be latched, remove the shunt from JU4 to enable the input clock; otherwise, leave the shunt in place.
2) Remove the shunt from JU5 to enable the output. Note: When performing the following resistance checks, manually set the ohmmeter to a high resistance range to avoid forward biasing the on-chip ESD-protection diodes. 3) Adjust R41, the MODSET potentiometer, for 10k resistance between test point 3 and ground. 4) Adjust R42, the BIASMAX potentiometer, for 10k resistance between test point 2 and ground. 5) Adjust R40, the APCSET potentiometer, for 10k resistance between test point 8 and ground. 6) Apply a differential input signal (max amplitude 800mV per side) to J7 and J8 (DATA+ and DATA-).
2
_______________________________________________________________________________________
MAX3850 Evaluation Kit
7) If the latch is enabled, apply a differential clock signal (max amplitude 800mV per side) to J5 and J6 (CLK+ and CLK-). 8) Attach a high-speed oscilloscope with 50 inputs to J9. 9) Power up the board with a +3.3V supply 10) Adjust R40 until the desired laser bias current is achieved. V - VTP12 IBIAS = TP13 15 Note: The APC function can only subtract from the maximum programmed bias current (set by the BIASMAX resistor, R42). If an APC failure flags before the desired bias current is achieved, increase the maximum bias current by tuning R42 counterclockwise. 11) Adjust R41 until the desired laser modulation current is achieved. IMOD = Signal amplitude (V) 15
Optical Evaluation
For optical evaluation of the MAX3850, configure the evaluation board as follows: 1) If data is to be latched, remove the shunt from JU1 to enable the input clock. Otherwise, leave the shunt in place. 2) Remove the shunt from JU2 to enable the output. 3) The EV kit is designed to allow connection of various laser/monitor diode pin configurations. Connect a TO-header style laser with monitor diode (Figure 1) as follows: * Keeping its leads as short as possible, connect the laser diode to two of the three pads in the cut-out portion on the top (component) side of the PC board. Solder the laser diode cathode to the center pad, and solder the anode to either of the other two pads, which are both connected to VCC. * Connect the monitor photodiode to two of the five pads on the bottom (solder) side of the PC board, directly below the laser diode pads. Three of these pads (the middle and outside positions) initially are not connected. The other two pads are connected to VCC. Solder the anode and cathode of the monitor photodiode to any two of the three pads that are not connected. Then connect the anode to the MD pin by shorting the corresponding solder jumper (Figure 1). Connect the cathode to V CC by using solder to bridge to an adjacent VCC pad.
Evaluates: MAX3850
Note: Because DC voltage at the output is approximately VCC/2, an SMA attenuator might be required.
Adjustment and Control Descriptions (see Quick Start first)
COMPONENT OPTICAL JU1 JU2 None R14 R15 ELECTRICAL JU4 JU5 J9 R41 R42 NAME Clock Disable Output Disable Electrical Output SMA MOD BIAS FUNCTION Enables/disables the clock input. Shunt for direct data transition. Remove shunt to enable the clock input. Enables/disables the output currents. Shunting disables the output currents. Remove shunt for normal operation. Electrical output. Adjusts the laser modulation current. Adjusts the laser bias current. In open-loop mode, R42 or R15 adjusts the laser bias current. In closed-loop operation, R40 or R16 adjusts the maximum laser bias current. For closed-loop operation, R40 or R16 adjusts the monitor diode current level. TTL low level indicates a failure in the APC loop. Refer to the Design Procedure section of the MAX3850 data sheet. Set APC current, then increase bias current until the LED goes off (the LED is illuminated when the APC loop is open, and off when the APC loop is closed).
R16 TP1 D1
R40 TP10 D3
APC Fail Indicator Fail Indicator
_______________________________________________________________________________________
3
MAX3850 Evaluation Kit Evaluates: MAX3850
Note: When performing resistance checks, manually set the ohmmeter to a high resistance range to avoid forward-biasing the on-chip ESD protection diodes. 4) Adjust R14, the MODSET potentiometer, for maximum resistance between test point 5 and ground. 5) Adjust R15, the BIASMAX potentiometer, for maximum resistance between test point 4 and ground. 6) Adjust R16, the APCSET potentiometer, for desired optical power. (Refer to the Design Procedure section of the MAX3850 data sheet. Note that R3 adds 1k to the total resistance.) 7) Apply a differential input signal (max amplitude 800mV per side) to J1 and J2 (DATA+ and DATA-). 8) Apply a differential clock signal (max amplitude 800mV per side) to J3 and J4 (CLK+ and CLK-). 9) Attach the laser diode fiber connector to an optical/electrical converter. 10) Power up the board with a +3.3V supply. 11) Adjust R15 until the LED (D1) no longer is illuminated. Optical power can be observed on an oscilloscope connected to an optical/electrical converter. 12) Adjust R14 until the desired optical amplitude is achieved. Optical amplitude can be observed on an oscilloscope connected to an optical/electrical converter.
4
_______________________________________________________________________________________
MAX3850 Evaluation Kit Evaluates: MAX3850
CONFIGURATION 1 CONFIGURATION 2
TOP OF PC BOARD
TOP OF PC BOARD
LD
TO-46 CAN LASER/PHOTODIODE PAIR
LD
TO-46 CAN LASER/PHOTODIODE PAIR
BOTTOM OF PC BOARD PD PD
BOTTOM OF PC BOARD
SOLDER BRIDGES
VCC
VCC
SOLDER BRIDGES
CONFIGURATION 3
CONFIGURATION 4
TOP OF PC BOARD
TOP OF PC BOARD
TO-46 CAN LASER/PHOTODIODE PAIR
LD
TO-46 CAN LASER/PHOTODIODE PAIR
LD
BOTTOM OF PC BOARD
PD
BOTTOM OF PC BOARD
PD
VCC
VCC
SOLDER BRIDGES
SOLDER BRIDGES
PAD LAYOUT
GND GND GND
Figure 1. Attachment of Laser/Monitor Diode to the MAX3850 EV Kit _______________________________________________________________________________________ 5
VCC VCC VCC
VCC
GND
Evaluates: MAX3850
R40 100k VCC TP3 R47 1.5k VCC TP13 TP2 2 Q2 1 4 3 R5 1.5k MD R6 OPEN VCC C25 0.01F 32 VCC2 GND CAPC VCC3 BIASMAX MODSET APCSET C26 0.1F N.C. VCC C43 1000pF MD GND3 U2 GNDM VCC4 VCC 20 19 18 17 BIAS GND VCC4 BIAS 15 16 VCC TP12 R49 75 VCC C7 0.5pF OUTOUT+ VCC4 21 GND GND 22 23 GND R17 30.1 C8 1.0pF R4 30.1 Z0 = 30 R44 30.1 24 1 C27 0.1F C28 0.01F DATAVCC1 4 5 CLK+ CLKVCC1 LATCH ENABLE GND BIASMON MODMON FAIL APCFILT 6 C30 0.1F 7 VCC 8 R32 100 3 R28 100 VCC1 2 DATA+ 31 30 29 28 27 26 25 MD VCC R22 1.5k R23 1k C42 0.1F 3 6 BIAS 7 U3 2 R46 15 C45 0.01F VCC TP8
MAX3850 Evaluation Kit
Figure 2. MAX3850 EV Kit Electrical Configuration Schematic
TP11 VCC R41 50k C40 10F C41 0.01F R42 200k
6
MAX495
APC TEST CIRCUIT C24 0.01F C29 0.1F
R38 49.9
TP21
VCC
L9 220nH
TP22
GND
DATA+
J7
DATA-
J8
MAX3850
CLK+
J5
Z0 = 30
CLK-
J6
J9 OUT
JU4 JU5 9 10 11 12 13 14
VCC
C33 0.1F R37 392 TP17 TP10 D3 LED VCC R34 110
_______________________________________________________________________________________
C32 0.01F VCC R43 392 TP18
TP6 R16 100k
R21 49.9 TP14 VCC1 R14 50k TP5
TP19 C19 10F R1 1.5k VCC1 C1 0.01F 32 N.C. SB1 SB6 GND VCC1 GND R27 16.2 R20 11 VCC1 VCC1 20 19 18 17 R36 49.9 C35 8.2pF SB5 SB4 654 PHOTODIODE VCC1 U4* 1 2 3 LASER C36 0.01F C17 0.01F C38 0.01F C22 0.01F VCC2 GND CAPC VCC3 MODSET APCSET C10 0.1F VCC1 C6 VCC1 1000pF MD GND3 U1 GNDM VCC4 OUTOUT+ VCC4 BIAS GND VCC4 21 22 23 24 1 C11 0.1F C3 0.01F R8 100 BIASMAX 31 30 29 28 27 26 25 SB2 SB3 *NOTE: SEE FIGURE 1 FOR DETAILS OF U4 CONNECTION VCC1 R2 1.5k R3 1k C16 0.1F C20 0.01F R15 200k TP4
VCC
L4 220nH
TP20
GND
ENABLE
GND
BIASMON
MODMON
FAIL
JU2
9
10
11
12
13
APCFILT
Figure 3. MAX3850 EV Kit Optical Configuration Schematic
C2 0.01F C12 0.1F
DATA+
J1
DATA-
J2
MAX3850
CLK+ C13 0.1F VCC1 R12 100
J3
CLK-
J4
VCC1 2 DATA+ 3 DATA4 VCC1 5 CLK+ 6 CLK7 VCC1 8 LATCH L2 MURATA BLM18HG601SNI VCC1 C4 0.01F TP1 VCC1 D1 R19 TP15 392 R18 110 VCC1 C5 0.1F
JU1 14 15 16
VCC1 TP16 R35 392
Evaluates: MAX3850
_______________________________________________________________________________________
MAX3850 Evaluation Kit
7
MAX3850 Evaluation Kit Evaluates: MAX3850
1.0"
1.0"
Figure 5. MAX3850 EV Kit PC Board Layout--Component Side
Figure 4. MAX3850 EV Kit Component Placement Guide-- Component Side 8
_______________________________________________________________________________________
MAX3850 Evaluation Kit Evaluates: MAX3850
1.0"
Figure 6. MAX3850 EV Kit PC Board Layout--Solder Side
1.0"
Figure 7. MAX3850 EV Kit PC Board Layout--Ground Plane
_______________________________________________________________________________________
9
MAX3850 Evaluation Kit Evaluates: MAX3850
1.0"
Figure 8. MAX3850 EV Kit PC Board Layout--Power Plane
1.0"
Figure 9. MAX3850 EV Kit Component Placement Guide-- 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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 10 (c) 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.

▲Up To Search▲

Price & Availability of MAX3850EVKIT

	To Download MAX3850EVKIT Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .