_______________general description the max459 evaluation kit (ev kit) simplifies the evalua- tion of the max458 and max459 video crosspoint switches. the max459 is already installed and a sam- ple max458 can be ordered from maxim. simply replace the max459 with the max458; no other changes are necessary. the kit includes an assembled printed circuit board, a 5 1/4" program disk, and a data sheet. this manual pro- vides easy instructions for using the ev kit. separate sections describe driving coaxial cables, controlling serial/parallel address modes, and daisy chaining mul- tiple ev kits. ____________________________features ? 100mhz bandwidth (max458) 90mhz bandwidth (max459) ? low differential gain/phase error ? 75 w output impedance ? 300v/ m s slew rate ? 70ns channel switching time ? high-z amplifier output capability ? 16-bit serial and 6-bit parallel address modes ? pc-compatible software for controlling serial and parallel address modes note: to evaluate the max458, request a max458cqh sample. max459 ev kit max459 evaluation kit ________________________________________________________________ maxim integrated products 1 call toll free 1-800-998-8800 for free samples or literature. part temp. range board type MAX459EVKIT-plc 0? to +70? surface mount qty component description u1 1 maxim max459cqh c1, c2 2 10 m f, 10v tantalum capacitors c3, c4 2 0.1 m f ceramic capacitors r1?12 12 75 w , 5% resistors r13, r14 2 50k w , 5% sip resistors r15, r16, r17 3 500 w , 5% sip resistors sw1 1 12-position dip switch label ____________________component list ______________ordering information j1 1 26-pin male connector in0?n7, out0?ut3 12 bnc jacks _________________________quick start the max459 ev kit is fully assembled and tested. to verify board functionality, follow these quick start instructions. do not turn on the power supply until all connections are completed. 1) connect a +5v supply to the pad marked v cc . connect a -5v supply to the pad marked v ee . connect power supply ground to the pad marked gnd. 2) connect the output marked out0 to an oscillo- scope through a terminated 75 w cable. 3) set all logic control switches on sw1 to logic low, except c s , which should be set to logic high. 4) turn on the power supply. 5) apply a signal ( 1.25v max) to the bnc jack input marked in0. 6) verify the output signal on the oscilloscope. 7) refer to the controlling parallel/serial modes sec- tion for changing address modes.
max459 ev kit max459 evaluation kit 2 _______________________________________________________________________________________ _______________detailed description the max458/max459 operate on 5v, allowing output signal levels of 2.5v. bnc jacks are provided for all input and output signals. design architecture ensures that no two inputs will be shorted together. and, a digitally con- trolled shutdown mode reduces power consumption. the parallel address mode can be set manually or through software. and, multiple ev boards can be daisy-chained to form larger switch arrays. driving coaxial cables high-speed performance, excellent output current, and an internally fixed gain of 2v/v make the max459 ideal for driving 50 or 75 w back-terminated coaxial cables. the ev kit is configured with 75 w terminating resistors on all inputs, and 75 w back-terminating resistors on all outputs for 75 w coaxial-cable matching. using the max459 results in an overall gain of one at the terminated cable? output. with the max458 installed, the overall gain is reduced to one-half the input signal when driving a terminated cable. layout considerations the max459 ev kit layout is optimized for high-speed signals. each signal trace is kept the same length and as short as possible to maintain phase relationship and minimize inductance. separate ac grounds surround each signal trace to reduce coupling. further layout recommendations can be found in the grounding and bypassing, pc board layout section of the max458/max459 data sheet. controlling parallel/serial modes a digital interface for parallel address modes can be established manually with dip switches or with pc-com- patible software. serial-interface control is established only through serial software (see the software control section). for details on the operation and for truth tables, refer to the digital section?arallel/serial mode sections of the max458/max459 data sheet. manual control dip switch sw1 provides manual control of the logic inputs in parallel mode. all logic input lines have 50k w pull-up resistors to +5v. 1) set all switches on sw1 to logic low, except cs , update , and wr , which should be set to logic high. 2) select an output amplifier with switches a0 and a1. to disable an output amplifier, set d3 to logic high. 3) select an input for the output selected in step 2 with switches d0?2. 4) pulse wr low to latch input registers. 5) pulse update low to latch the switch registers and update the outputs. refer to text under digital section?arallel mode and tables 1? of the max458/max459 data sheet for more details of operation and truth table. the ev kit will not respond properly to manual control if the interface cable (as described below) connects the board to the parallel port of the pc. software control applications software comes with the max459 ev kit for programming serial or parallel address modes. 459evkit.bas is the source code written in microsoft quickbasic. 459evkit.exe is the compiled program that is executable from the dos command line. it uses the computer? ?pt1?output to interface to the ev board. follow the instructions below for serial or parallel digital control: 1) set all switches on sw1 high (except shdn) prior to starting the computer program. 2) connect an interface cable from the computer? parallel port to the evaluation board. recommended cable and connectors are: 26-conductor ribbon cable d-subminiature 25-pin, male, crimp-type connector 26-pin idc crimp-type socket connector the ev kit board and software are designed for a ?traight-through?cable configuration. table 1 shows the pin assignments for the cables. 3) load the disk and type the command 459evkit. 4) select serial or parallel address mode. once the user selects a mode, the program displays a valid list of input commands. the program displays the current state of the input and switch registers.
parallel address mode there are 4 amplifiers that can be configured individu- ally as follows: 1) select a valid amplifier (0?) and a valid input (0?). with c e low and w r high, the program presents the input/output information to the chip at a0, a1 and d0?3. the program pulses w r low as each input is selected, and the data is then latched into the input registers. 2) to latch the switch registers and update the out- puts, select the latch command code l. this puls- es the u p d a t e line low. 3) to disable the selected amplifier, select d. the program places d3 high and pulses w r low. select l to latch the data. during parallel mode, the program keeps c s high and sclk and din low. input codes: 0 7 sets the selected input channel and output amplifier (0? only). l latches switch registers and updates outputs. d disables specified output amplifier. e exits program. serial address mode in serial address mode, amplifiers 0? are configured with 16 bits of data in 4-bit blocks (d3?0) as follows: 1) enter four input settings to set up the amplifiers. 2) update the outputs to the current input settings, by selecting latch command l. the program then pulses c s high. outputs remain unchanged until the rising edge of c s . 3) to disable an output, select d. input codes: 0? sets the selected input channel. l latches switch registers and update outputs. d disables output amplifier. e exits program. during serial mode, the program keeps w r , u p d a t e , and c e high. daisy-chain configuration multiple ev boards can be daisy-chained and separat- ed in serial address mode to form larger switch arrays. to form a chain: 1) connect dout of the first board to din of the sec- ond board. 2) tie c s from each board together and sclk from each board together, as shown in figure 12 of the max458/max459 data sheet. the boards will be programmed in a first-in, first-out (fifo) manner. for example, the second board in the chain will receive its first 4-bit block when the first board receives its fifth 4-bit block. max459 ev kit max459 evaluation kit _______________________________________________________________________________________ 3 table 1. cable pin assignments ev kit board (j1) pin pin signal 1 1 w r 2 3 d0 3 5 d1 4 7 d2 5 9 d3 6 11 a0 7 13 a1 8 15 din 9 17 sclk 14 2 u p d a t e 16 6 c s 17 8 c e 10 19 no connect 11 21 no connect 12 23 no connect 13 25 no connect 15 4 no connect 18?5 10, 12, 14, 16, 18, 20, 22, 24, 26 gnd parallel port (lpt1) signal strobe data bit 0 data bit 1 data bit 2 data bit 3 data bit 4 data bit 5 data bit 6 data bit 7 auto feed init. prt. select ack busy paper end select in error bit 0? gnd
max459 ev kit max459 evaluation kit 4 _______________________________________________________________________________________ out0 38 in0 4 v cc r1
75 w r9
75 w 7 in1 r2
75 w out1 36 in2 9 r3
75 w r10
75 w in3 11 r4
75 w out2 34 in4 13 r5
75 w r11
75 w in5 15 r6
75 w out3 out0 out1 out2 out3 shdn a1 d1 a0 d0 d2 d3 wr cs update ce din sclk dout 31 21 29 28 27 26 25 23 42 41 40 44 1 43 20 21 24 23 22 14 15 16 17 18 19 13 11 13 3 5 7 9 2 1 8 6 15 17 22 in6 17 r7
75 w r12
75 w in7 in0 in1 in2 in3 in4 in5 in6 in7 19 r8
75 w 50k w 500 w r13g r15a r15b r15c r15d r15e r17a r16c r16d r16a r16e r17b r16b v cc v cc v cc v ee v ee r13a r13b r13c r13d r13e r13f r14e r14f r14g r14c r14a r14d 2 3 6 5 8 10 16 18 24 20 30 32 37 39 33 14 v ee 12 35 c1
10 m f
10v c3
0.1 m f c4
0.1 m f c2
10 m f
10v j1 dip
switch
sw1 gnd max458/max459 parallel
interface serial
interface 5 4 1 231110987612 figure 1. max459 ev kit schematic
max459 ev kit max459 evaluation kit _______________________________________________________________________________________ 5 figure 2. max459 ev kit component placement guide?omponent side
max459 ev kit max459 evaluation kit 6 _______________________________________________________________________________________ figure 3. max459 ev kit component placement guide?older side
max459 ev kit max459 evaluation kit _______________________________________________________________________________________ 7 figure 4. max459 ev kit pc board layout?omponent 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. 8 ___________________maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 (408) 737-7600 1994 maxim integrated products printed usa is a registered trademark of maxim integrated products. max459 ev kit max459 evaluation kit figure 5. max459 ev kit pc board layout?older side
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