Evaluates: MAX3946 19-5755 Rev 0 2/11 MAX3946 Evaluation Kit General Description Features The MAX3946 evaluation kit (EV kit) is an assembled S Drives Differential-Connected Lasers demonstration board that provides optical evaluation S Software Control of the MAX3946 of the MAX3946 1.0625Gbps to 11.3Gbps laser driver. S Power Supplied Through USB or External The controlling software communicates with the EV kit Connection through the USB port and provides simplified control of all the device functions. The EV kit can be fully powered by the USB port, or the user can choose to power the device by a single external 3.3V supply Ordering Information while the USB port supplies the on-board microcon- troller. The flex-cable connection on the EV board PART TYPE allows attachment of lasers incorporating flex cables. MAX3946EVKIT EV Kit EV Kit Contents S MAX3946 EV Kit Board Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION C1C6, C8, C9, 0.01FF Q10% ceramic L10, L14, 10 4 10FH Q10% inductors (0603) C16, C41 capacitors (0402) L15, L16 R1, R2 2 1.00kI Q1% resistors (0402) C7, C10, C12, 0.1FF Q20% ceramic capacitors 4 C14 (0204) R3 1 680I Q5% resistor (0402) R5, R6 2 20I Q5% resistors (0603) 10FF Q10% ceramic capacitors C11, C13, C15 3 (0805) R7, R8 2 100I Q5% resistors (0603) C17C20 0 Not installed R15, R50 2 4.7kI Q5% resistors (0402) R16, R17 2 1kI Q5% resistors (0402) 33pF Q10% ceramic capacitors C21, C22 2 (0402) R18, R52, R55, 5 51I Q5% resistors (0402) R66, R73 C25, C26, C27, 0.1FF Q10% ceramic capacitors 5 C49, C52 (0402) R24 1 1.5kI Q5% resistor (0402) R31, R51, R53 3 10kI Q5% resistors (0402) 1FF Q10% ceramic capacitors C34, C55 2 (0603) SW1 1 SPDT switch 4.7FF Q10% ceramic capacitors 1.0625Gbps to 11.3Gbps, SFP+ C35, C37, C38 3 (0805) U1 1 laser driver (24 TQFN-EP*) Maxim MAX3946ETG+ D6 1 Green LED J1, J2 2 SMA edge-mount connectors Low-noise LDO regulator U2 1 (8 TDFN-EP*) J3, J4, TP3, TP7, 8 Test points Maxim MAX8902AATA+ TP10TP13 J8 1 USB connector U6 0 User-supplied TOSA JU2 1 2 x 6 header, 0.1in centers Microcontroller (28 SO) U10 1 Microchip PIC16C745-I/SO 22FH Q20% inductor L1 1 Taiyo Yuden CBC3225T220M 6MHz crystal Y2 1 ECS Inc. ECS-60-32-5PXDN L2, L3 2 18nH Q2% inductors (0402) Ferrite beads (0402) PCB: MAX3946 EVALUATION L4, L11, L12 3 1 Murata BLM15GG471 BOARD, REV A *EP = Exposed pad. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.MAX3946 Evaluation Kit 7) Connect a 50I source to TIN- and TIN+ (J1 and J2). Quick Start Set the source differential amplitude to 500mV . P-P Note: In the following sections, software-related items 8) Connect the output from the TOSA to an optical are identified by bolding. Text in bold refers to items receiver (optical-to-electrical converter or optical directly from the EV kit software. Text in bold and input head on an oscilloscope). M underlined refers to items from the Windows operating 9) All device controls are available in the software. system. Fault and warning indicators are displayed on the 1) Solder a laser to connection U6. See Figure 1 for right side of the graphical user interface (GUI) more information about the laser connection. window. When a hard fault has occurred the device 2) Set SW1 to the desired power-supply option (USB goes into latched shutdown. The source of the fault or external supply). should be removed and the DISABLE checkbox should be toggled to reset the part. 3) If an external power supply is used, set the voltage to 3.3V, the current limit to 300mA, and connect the 10) The registers contain a default setting and can be supply to the board. read using the Tx Read All button. For detailed reg- ister functions, refer to the MAX3946 IC data sheet. 4) To download the latest version of the EV kit software (MAX3946Rev1.ZIP), visit the Maxim website at 11) To enable the part, the DISABLE checkbox should www.maxim-ic.com/evkitsoftware. Unzip the file be toggled (checked and then unchecked) and the to a local folder and run the installation file (setup. Tx Enable checkbox should be checked. After doing EXE). Installation requires administrative rights and this, click the Tx Read All button twice and verify can also require Internet access to download nec- whether any faults are indicated. All fault indicators essary drivers. should be green if everything is set up properly. 5) After installation is complete, follow this path 12) The Tx De-emphasis Control edit box can be used to start the program: Start All Programs to adjust the eye diagram. After choosing a new MAX3946EVGUI MAX3946EVGUI. setting, click the Tx De-emphasis Control edit box Load button followed by the IMod edit box Load 6) Connect the computer to the EV kit with a USB cable button. Doing so loads the new preemphasis setting (A-male to Mini-B-male). LED D6 should illuminate, to the modulation current driver. Further improve- indicating that USB power is detected. Click the USB ments to the eye diagram can be accomplished by Connect button in the software to initiate communica- adjusting the component values of L2, L3, L11, L12, tion to the EV kit. The Status indicator turns green and R5R8. when communication is established. 1 U6 Figure 1. TOSA Connection Windows is a registered trademark of Microsoft Corp. 2 Evaluates: MAX3946 N.C. GND LD ANODE LD CATHODE GND N.C.