MAX3874EVKIT中文资料
_________________________________________________________________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 https://www.wendangku.net/doc/0a19018893.html,.
Evaluate: MAX3872/MAX3874
MAX3872/MAX3874 Evaluation Kits
________________General Description
The MAX3872/MAX3874 evaluation kits (EV kits) simplify evaluation of the MAX3872 and MAX3874 clock and data recovery with limiting amplifier ICs. These EV kits enable testing of all MAX3872 and MAX3874 functions. SMA connectors are provided for the differential inputs and outputs. All high-speed inputs and outputs have on-board AC-coupling capacitors to allow direct connection to 50?test equipment.
____________________________Features
? SMA Connectors for All High-Speed I/Os ? Operational Mode Select Pins ? Loss-of-Lock LED
? Single +3.3V Power-Supply Operation ? Fully Assembled and Tested
______________Ordering Information
PART TEMP. RANGE IC PACKAGE MAX3872EVKIT -40°C to +85°C 32 QFN MAX3874EVKIT -40°C to +85°C 32 QFN
______________Component Suppliers
SUPPLIER
PHONE FAX AVX 843-448-9411843-626-3123Coilcraft 847-639-6400847-639-1469Digi-Key 800-344-4539218-681-3380EF Johnson 402-474-4800402-474-4858Murata
770-436-1300
770-436-3030
Note: Please indicate that you are using the
MAX3872/MAX3874 when ordering from these suppliers.
______________________________________________________________Component List
DESIGNATION QTY DESCRIPTION
C1–C7, C17–
C19, C22, C24,C26, C28140.1μF ±10% ceramic capacitors (0402)Murata GRM36X7R104K016A
C8–C136
0.001μF ±10% ceramic capacitors (0402)Murata GRM36X7R102K016A C141
33μF ±10% tantalum capacitor
AVX TAJB336K016
C151
2.2μF ±10% tantalum capacitor
AVX TAJB225K016
0.82μF ceramic capacitor (0603) (MAX3872EVKIT)
C161
0.068μF ceramic capacitor (0402) (MAX3874EVKIT)
D11Red LED D21Not installed R2–R54Not installed R61910? ±5% resistor (0402)R71Not installed
R81
50k ? variable resistor
BOURNS 3296W-203
R91Not installed
L1–L33
56nH inductors (0805)
Coilcraft CS-560XKBC
DESIGNATION QTY DESCRIPTION
J1–J8, J25, J2610SMA connectors
(edge-mount, round-pin)
EF JOHNSON 142-0701-851J9, J12–J15,J17–J1983-pin headers (0.1in centers)J10
12-pin headers (0.1in centers)J11, J16, J22,
J234Not installed J20, J212Test points
Digi-Key 5000K-ND J24
1Not installed J9, J10, J12–J15, J17–J19
9
Shunts
MAX3872EGJ, 32-pin QFN (MAX3872EVKIT)
U1
1
MAX3874EGJ, 32-pin QFN (MAX3874EVKIT)
None 1
MAX3872/MAX3874 EV kit circuit board, Rev C MAX3872 datasheet (MAX3872EVKIT)None 1
MAX3874 datasheet (MAX3874EVKIT)
19-2767; Rev 0, 2/03
MAX3872/MAX3874 Evaluation Kits 2
________________________________________________________________________________________
E v a l u a t e : M A X 3872/M A X 3874
_______________Detailed Description
The MAX3872/MAX3874 EV Kit is a fully assembled and factory tested demonstration board that enables testing of all MAX3872 and MAX3874 functions.
Test Equipment Required
? +3.3V power supply with 200mA current capability ? Signal-source, 2.7Gbps minimum capability ? Jitter analyzer capable of 2.7Gbps performance ?
Oscilloscope with at least 3GHz performance
Test Equipment Interface
The serial inputs (SDI±, SLBI±) and serial outputs (SDO±, SCLKO±) have on-board AC-coupling capacitors to allow direct connection to 50? test equipment. The EV kit also has pads on the serial data and clock outputs (SDO±, SCLKO±) to allow on-board termination for coupling to high-impedance oscilloscopes.
Quick Start (MAX3872 & MAX3874)
This procedure will set up the evaluation board for 2.48832Gbps normal operation mode, with input threshold adjust disabled.
1) Place a shunt across pins 2 (SIS) and 3 (GND) of
J13.
2) Place a shunt across pins 1 (VCC) and 2 (LREF)
of J14.
3) Place a shunt across pins 2 and 3 of J15.
4) Place a shunt across pins 2 (RS1) and 3 (GND) of
J17.
5) Place a shunt across pins 2 (RS2) and 3 (GND) of
J18.
6) Place a shunt across pins 2 (RATESET) and 3
(GND) of J19.
7) Place a shunt across pins 1 (VCC) and 2 (VCTRL)
of J9.
8) Remove the shunt from J10.
9) Place a shunt across pins 2 (FREFSET) and 3
(GND) of J12.
10) Connect a 2.48832Gbps PRBS NRZ signal to the
serial data inputs (SDI±) with 50? cables. Leave the SLBI ± inputs unconnected.
11) Connect the serial data and clock outputs (SDO±,
SCLKO±) to a 50? high-speed oscilloscope.Terminate any unused outputs with 50? to GND.12) Connect +3.3V to J20 (VCC) and ground to J21
(GND).
Jitter analysis and product performance can also be observed by appropriately interfacing the EV kit with a bit-error-rate tester (BERT) and a jitter analyzer.
Operational Modes
The MAX3872/MAX3874 has three modes of operation: normal, system loopback, and clock holdover. The three operational modes are programmed by connecting the appropriate pins of JU13 (SIS) and JU14 (LREF). See Table 1. Normal operation mode requires a serial data stream at the SDI ± inputs, system loopback mode requires a serial data stream at the SLBI ± inputs, and clock holdover mode requires a reference clock signal at the SLBI ±inputs.
Normal and System Normal and System Loopback Settings Loopback Settings
Three jumpers (RS1, RS2, RATESET) are available for setting the SDI ± or SLBI ± inputs to receive the appropriate data rate (Table 2). The FREFSET pin can be set high or low while in normal or system loopback mode.
Clock Frequencies in Holdover Mode
Set the incoming reference clock frequency and outgoing serial clock frequency by setting RS1, RS2,RATESET, and FREFSET appropriately. See Table 3.
Auto Switch to Clock Holdover Mode
To switch from normal mode to clock holdover mode automatically when there are no data transitions applied to the SDI ± inputs connect LOL directly to LREF by placing a shunt across pins 1 and 2 of J15.
Vertical Threshold Adjustment
To compensate for optical noise presented on the data logic high caused by EDFAs in a WDM transmission system, an external analog control input is provided for adjusting the data decision threshold to an optimum level.
To enable data decision threshold adjustment, place a shunt across pins 2 and 3 of J9 and shunt pins 1 and 2of J10. Set the decision threshold by adjusting the potentiometer R8. The center point for the decision threshold is 1.2V at the VCTRL pin.
Jumpers, Controls, Test Points
Table 4 summarises the functions of all jumpers,controls, and test points of the MAX3872/MAX3874 EV Kit.
MAX3872/MAX3874 Evaluation Kits
_________________________________________________________________________________________ 3Evaluate: MAX3872/MAX3874
Table 1. Operational Mode Settings
Table 2. Data Rate Settings
SHUNT POSITIONS INPUT DATA RATE
RS1RS2RATESET 2.666Gbps 2 and 3 2 and 3 1 and 2 2.488Gbps/2.5Gbps 2 and 3 2 and 3 2 and 3 1.244Gbps/1.25Gbps* 1 and 2 1 and 2 2 and 3 666.51Mbps* 2 and 3 1 and 2 1 and 2 622.08Mbps* 2 and 3 1 and 2 2 and 3 166.63Mbps* 1 and 2 2 and 3 1 and 2 155.52Mbps* 1 and 2 2 and 3 2 and 3 *Setting not available on the MAX3874
Table 3. Clock Holdover Frequency Settings
SHUNT POSITIONS REFERENCE CLOCK FREQUENCY SCLKO FREQUENCY
RS1RS2RATESET FREFSET 666.51MHz 2.666GHz 2 and 3 2 and 3 1 and 2 2 and 3 666.51MHz*666.51MHz 2 and 3 1 and 2 1 and 2 2 and 3 666.51MHz*166.63MHz 1 and 2 2 and 3 1 and 2 2 and 3 622.08MHz/625MHz* 1.244GHz/1.25GHz 1 and 2 1 and 2 2 and 3 2 and 3 622.08MHz/625MHz 2.488GHz/2.5GHz 2 and 3 2 and 3 2 and 3 2 and 3 622.08MHz*622.08MHz 2 and 3 1 and 2 2 and 3 2 and 3 622.08MHz*155.52MHz 1 and 2 2 and 3 2 and 3 2 and 3 166.63MHz 2.666GHz 2 and 3 2 and 3 1 and 2 1 and 2 166.63MHz*666.51MHz 2 and 3 1 and 2 1 and 2 1 and 2 166.63MHz*166.63MHz 1 and 2 2 and 3 1 and 2 1 and 2 155.52MHz/156.25MHz* 1.244GHz/1.25GHz 1 and 2 1 and 2 2 and 3 1 and 2 155.52MHz/156.25MHz 2.488GHz/2.5GHz 2 and 3 2 and 3 2 and 3 1 and 2 155.52MHz*622.08MHz 2 and 3 1 and 2 2 and 3 1 and 2 155.52MHz*155.52MHz 1 and 2 2 and 3 2 and 3 1 and 2 *Setting not available on the MAX3874
MAX3872/MAX3874 Evaluation Kits 4
________________________________________________________________________________________
E v a l u a t e : M A X 3872/M A X 3874
Table 4. Jumpers, Controls, Test Points
MAX3872/MAX3874 Evaluation Kits
_________________________________________________________________________________________ 5Evaluate: MAX3872/MAX3874
Figure 1. MAX3872 EV Kit Schematic
MAX3872/MAX3874 Evaluation Kits
6
________________________________________________________________________________________
E v a l u a t e : M A X 3872/M A X 3874
Figure 2. MAX3874 EV Kit Schematic
MAX3872/MAX3874 Evaluation Kits
_________________________________________________________________________________________ 7
Evaluate: MAX3872/MAX3874
Figure 3. MAX3872/MAX3874 EV Kit Component
Placement Guide—Component Side
Figure 4. MAX3872/MAX3874 EV Kit PC Board Layout— Figure 5. MAX3872/MAX3874 EV Kit PC Board Layout—Component Side Ground Plane
MAX3872/MAX3874 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
2003 Maxim Integrated Products Printed USA
is a registered trademark of Maxim Integrated Products.
E v a l u a t e : M A X 3872/M A X 387
4
Figure 6. MAX3872/MAX3874 EV Kit PC Board Layout— Figure 7. MAX3872/MAX3874 EV Kit PC Board Layout—Power Plane Solder Side