general description the max5417l evaluation system (ev system) consistsof a max5417l evaluation kit (ev kit) and a companion command module interface board (cmodusb). the max5417l ev kit is an assembled and tested pc board that features the max5417l 50k , linear-taper digital potentiometer. the max5417l ic features an inter-nal nonvolatile eeprom used to store the potentiometer? wiper position for initialization during power-up. the eeprom is programmed through the i 2 c-compatible seri- al interface, transmitting at rates up to 400kbps. themax5417l is programmed with a factory-preset address and features an address input for a total of two unique address combinations. the max5417l ev kit can also be used to evaluate other versions of the max5417, max5418 (100k ), and max5419 (200k ) digital potentiometers.the ev kit also includes windows 98-/2000-/xp-compat- ible software that provides a professional user interfacefor exercising the max5417l? features. the program is menu-driven and offers a graphical user interface (gui) complete with control buttons and a track bar. the cmodusb command module allows a personal computer (pc) to use its usb port to emulate an i 2 c 2- wire interface. order the max5417levcmodu for acomplete pc-based ev kit. order the MAX5417LEVKIT if a cmodusb command module or an i 2 c-compatible 2-wire interface system has already been purchasedwith a maxim ev system. features ? power-on recall of wiper position fromnonvolatile memory ? 2.7v to 5.25v single-supply operation ? selectable device address input ? i 2 c-compatible serial interface ? easy-to-use menu-driven software ? include windows 98-/2000-/xp-compatiblesoftware and demo pc board ? evaluate the max5417/max5418/max5419 ? assembled and tested evaluate: max5417_/max5418_/max5419_ max5417l evaluation kit/evaluation system ________________________________________________________________ maxim integrated products 1 19-3733; rev 0; 6/05 for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. part temp range ic package i 2 c in t er f a c e in c l u d ed m a x5 4 1 7 l evk i t 0 c to + 70 c 8 td fn - e p * no m a x5 4 1 7 l evc m o d u 0 c to + 70 c 8 td fn - e p * yes ordering information * ep = exposed pad. note: to evaluate the max5417m ? /n ? /p ? , max5418_, or max5419_, request a free sample with theMAX5417LEVKIT. note: the max5417l ev kit software is provided with theMAX5417LEVKIT. however, the cmodusb command module is required to interface the ev kit to the computer when using the included software. ? future product?ontact factory for availability. windows is a registered trademark of microsoft corp. designation qty description c1 1 0.1? ?0%, 16v x7r ceramiccapacitor (0603) tdk c1608x7r1c104k c2 0 n ot i nstal l ed , cer am i c cap aci tor ( 0603) j1 1 2 x 10 right-angle receptacle ju1 1 3-pin header ju2 0 not installed, 2-pin header ju3 1 2-pin header designation qty description r1, r2 0 not installed, resistors (0805) u1 1 max5417leta(8-pin, 3mm x 3mm tdfn-ep) none 1 shunt (ju1) none 1 max5417l pc board none 1 software disk (cd-rom),max5417l ev kit MAX5417LEVKIT component list part qty description MAX5417LEVKIT 1 max5417l ev kit cmodusb 1 i 2 c interface board max5417levcmodu system component list downloaded from: http:///
quick start recommended equipment windows 98/2000/xp computer and a usb port usb cable (to connect the computer? usb port tothe cmodusb command module) 5v/100ma dc power supply ? hmmeter procedure the max5417l ev kit is fully assembled and tested.follow the steps below to verify board operation. do not turn on the power supply until all connectionsare completed: 1) carefully connect the boards by aligning the 20-pin connector (j1) of the max5417l ev kit with the p3 20-pin header on the cmodusb command mod- ule. gently press them together. 2) slide both cmodusb command module sw1 dip switches to the on position. ensure that jumper j1is installed in position 1-2, setting the command module for 5v operation. 3) verify that a shunt is installed across pins 1-2 ofjumper ju1 (device address = 0x52) on the max5417l ev kit. 4) verify that a shunt is not installed on jumper ju3 on the max5417l ev kit. 5) use the install.exe program on the providedcd-rom to copy the files and create icons in the windows 98/2000/xp start menu. 6) connect the 5v dc power supply to the vdd and gnd pads on the max5417l ev kit board. 7) connect the ohmmeter across the l and w pads. 8) turn on the power supply. 9) connect a usb cable from the computer? usb port to the cmodusb command module. note: do not connect a power source to the p1 connector on the command module. the command module is pow- ered through the usb port. 10) start the max5417l program by opening its icon in the start menu. 11) observe as the program automatically detects the address of the max5417l and starts the main program. 12) the max5417l ev kit is ready for additional testing. detailed description of hardware the max5417l ev kit is an assembled and tested pcboard that evaluates the max5417l linear-taper digital potentiometer. the max5417l has an end-to-end resis- tance of 50k ? . the i 2 c interface is used to program the potentiometer wiper among 256 tap positions. themax5417l features an internal nonvolatile memory (eeprom) used to store the wiper position for initializa- tion during power-up. the i 2 c-compatible serial inter- face can communicate at rates up to 400kbps toprogram the nonvolatile and the volatile memory of the max5417l. the max5417l is programmed with a factory-preset address and features a configurable address bit, a0, which can set the device address to one of two unique address combinations. the max5417l ev kit can also be used to evaluate other 50k ? digital potentiometers (max5417m/n/p), each with their own unique factoryaddress. to evaluate the four versions of the max5418 (100k ? ) or the four versions of the max5419 (200k ? ) digital potentiometers, ic replacement is required. evaluate: max5417_/max5418_/max5419_ max5417l evaluation kit/evaluation system 2 _______________________________________________________________________________________ supplier phone fax website tdk 847-803-6100 847-390-4405 www.component.tdk.com component supplier note: indicate that you are using the max5417l when contacting this component supplier. downloaded from: http:///
address selection jumper ju1 sets the unique max5417l slave address.the two possible hex addresses are 0x50 or 0x52. see table 1 for jumper settings to set the max5417l slave address. note: the first 7 bits shown are the address. the y bit in table 1 is the i 2 c read/write bit. the i 2 c protocol states that this bit is a 1 for a read operation or a 0 for awrite. the y bit is always set to 0 (write only) because these digital potentiometers do not transmit data to the master device. i 2 c clock and data inputs the max5417l ev kit features a 2 x 10, right-angleheader receptacle (j1) to interface with the cmodusb command module. pin j1-7 connects to the max5417l clock pin (scl) and pin j1-3 connects to the data pin (sda) for i 2 c-compatible communications. slide both sw1 dip switches on the command module to the onposition to connect pullup resistors to the scl and sda signal lines for proper i 2 c communication. the clock and data input pins can also be accessed atthe scl and sda ev kit pads, respectively. an external i 2 c-compatible controller can be connected to the scl, sda, and gnd pads to communicate with themax5417l ic. if the external device does not have pullup resistors on the clock and data lines, 2.4k ? (typ) pullup surface-mount resistors (0805 size) must beinstalled on resistor r1 and r2 pads for proper i 2 c communication. the gnd pad must also be connectedto the external i 2 c controller. digital potentiometer pins the high (h), low (l), and wiper (w) pins of themax5417l digital potentiometer can be accessed at the ev kit? h, l, and w pads, respectively. jumper ju3 can be used to connect the l pin to the circuit ground thus providing a ground reference during evaluation. power input the max5417l ev kit requires a 2.7v to 5.25v powersupply connected across the vdd and gnd pads for normal operation. the ev kit can also use the cmodusb command module? 3.3v or 5v power source by installing a shorting jumper across ju2 of themax5417l ev kit. configure the command module? vdd select voltage to 3.3v or 5v (jumper j1) when using the command module to power the max5417l ev kit. note: ensure that all the data sheet absolute maximum specifications are not violated when operating themax5417l ev kit. evaluating other versions of the max5417/max5418/max5419 ics the max5417l ev kit pc board can be used to evalu- ate other addressing options of the max5417, max5418, or max5419 digital potentiometers. remove the max5417l ic (u1) and replace it with the new ic (see the interface section). refer to the max5417/ max5418/max5419 data sheet for a complete descrip-tion of part-to-part differences. detailed description of software note: words in boldface are user-selectable features in the software. user-interface panel the user interface (shown in figure 1) is easy to operate. use the mouse, or press the tab key to navigate through the gui controls. the correct i 2 c write operation is gen- erated to update the internal memory registers of themax5417l when any of these controls are used. the software divides ev kit functions into logical blocks. the interface box indicates the current device type , device address , i2c bus speed , ev kit status, and the last write operation command sent and data sent indi- cators. this data is used to confirm proper device opera- tion. the potentiometer control box changes the wiper position and transfers the data from the volatile memory to the nonvolatile memory or vice-versa. the max5417l ev kit software features additional func- tions to simplify operation. automatic diagnostics continually probe the interface board and themax5417l ev kit to make sure that all connections are maintained and that all devices are working properly. evaluate: max5417_/max5418_/max5419_ max5417l evaluation kit/evaluation system _______________________________________________________________________________________ 3 max5417l address shunt position max5417l address a0 pin binary hexadecimal 1-2 connected to vdd 0101 001y 0x52 2-3 connected to gnd 0101 000y 0x50 table 1. jumper settings for device address (ju1) downloaded from: http:///
evaluate: max5417_/max5418_/max5419_ these functions create some activity on the i 2 c bus. the silence i2c activity checkbox reduces i 2 c bus activity to the max5417l ev kit to enable easy trigger- ing of an oscilloscope. the factory reset button pro- grams the volatile and nonvolatile memory to midscale(wiper position = 127). software startup the max5417l ev kit software automatically searchesfor the cmodusb and the max5417l ev kit during startup. the status indicator shows if the interface board and the max5417l ev kit are operational. if the interface board is not found, verify that the command module and the usb cable are connected properly, power is applied to the ev kit, and click the yes button on the retry-connection message box. the nonfunctional gui can be viewed by clicking the no button on the retry-connection message box when attempting to start the software without the cmodusb being connected. restart the software with the com- mand module and ev kit properly connected for normal operation. wiper position the trackbar in the potentiometer control box can be used to change the wiper position between the h and lend points. use the computer mouse, arrow keys, or page-up/page-down keys to move the trackbar between the 256 position points. the wiper position canalso be changed by entering the numerical position (0 to 255) in the volatile edit fields. a trackbar or volatile edit field change writes to the volatile memory (0x11command) and the wiper position is updated with the data sent. the data in the nonvolatile memory remains unchanged. the position of the wiper is shown in the volatile edit fields. the top volatile field shows the wiper position with respect to the h end point and thebottom volatile field shows the wiper position with respect to the l end point. during ev kit power-up, thedata (wiper position) in the nonvolatile memory is trans- ferred to the volatile memory and the wiper position is updated. the volatile and non-volatile edit fields dis- play ???after initializing the ev kit software becausethe max5417l does not transmit data to the master. max5417l evaluation kit/evaluation system 4 _______________________________________________________________________________________ figure 1. max5417l ev kit software main window downloaded from: http:///
evaluate: max5417_/max5418_/max5419_ max5417l evaluation kit/evaluation system _______________________________________________________________________________________ 5 nonvolatile programming the non-volatile edit fields can be used to program the nonvolatile memory of the digital potentiometer. whenwriting to the nonvolatile memory (0x21 command), the volatile memory and the wiper position remain unchanged. the non-volatile edit fields accept the numerical position from 0 to 255. the top non-volatile edit field shows the wiper position with respect to the hend point and the bottom non-volatile edit field shows the wiper position with respect to the l end point. volatile/nonvolatile data transfer the potentiometer control box contains buttonsvreg->nvreg and nvreg->vreg that are used to transfer data from the volatile memory to the nonvolatilememory and the nonvolatile memory to the volatile mem- ory. when the vreg->nvreg button is clicked, the data present in the volatile memory is transferred to the non-volatile memory (0x51 command). when the nvreg->vreg button is clicked, the data present in the nonvolatile memory is transferred to the volatile mem-ory (0x61 command) and the wiper position is updated. these commands do not send any new data to the device because the commands transfer data already contained in the volatile or nonvolatile registers. interface the max5417l ev kit software automatically searchesfor the max5417l during startup using the two possible addresses: 0x50 or 0x52. if the software finds the max5417l digital potentiometer, the status indicator shows the max5417l is operational or if it is not found, the status indicator shows that the max5417l was not found and the device address is set to ??? when evaluating other versions of the max5417 or the max5418/max5419 digital potentiometers, use the device type combo box to select the correct device and select the auto detect option from the device address combo box, after starting the max5417l ev kit software.use the i2c bus speed combo box to set the bus speed to 400khz or 100khz. simple i 2 c commands there are two methods for communicating with themax5417l ev kit; through the normal user-interface panel (figure 1) or by using low-level i 2 c commands available through the 2-wire interface diagnostic (figure 2) item from the main program? options main menu. a window is displayed that allows i 2 c operations, such as read byte and write byte . the read byte operation is not used because the max5417l does notsend data to the master. to stop normal user-interface execution so that it does not override the manually set values, turn off the update timer by unchecking the automatic diagnostics checkbox in the max5417l main program.the i 2 c dialog boxes accept numeric data in binary, decimal, or hexadecimal. hexadecimal numbersshould be prefixed by $ or 0x. binary numbers must be exactly eight digits. see figure 2 for an example of this tool. figure 2 shows a simple smbus write-byte oper- ation using the included 2-wire interface diagnostics. in this example, the software is writing data 0x4e to the register address 0x11 (volatile memory) of the device with device address 0x50. the above data sequence sets the wiper position of the max5417l to position 78. general troubleshooting problem: software reports it cannot find the board. is the cmodusb command module power led(led1) lit? is the usb communications cable connected? has windows plug-and-play detected the board?bring up control panel, then system, then device manager, and look at what device nodes are indicat- ed for usb. if there is an ?nknown device?node attached to the usb, delete it. this forces plug-and- play to try again. problem: unable to find device-under-test (dut). is power connected to the max5417l ev kit? are the scl and sda signals pulled up to vddthrough appropriate resistors (2.4k ? typ)? the cmodusb command module dip switch sw1enables the on-board resistors. there must be pullup resistors somewhere on the i 2 c bus. if using jumper wires to connect, could the scl andsda signals be swapped? could the ground return be missing? smbus is a trademark of intel corporation. downloaded from: http:///
evaluate: max5417_/max5418_/max5419_ max5417l evaluation kit/evaluation system 6 _______________________________________________________________________________________ figure 2. simple smbus write-byte operation downloaded from: http:///
evaluate: max5417_/max5418_/max5419_ max5417l evaluation kit/evaluation system _______________________________________________________________________________________ 7 vdd vbus vbus vdd v dd scl r1 open c2 open ju2 open ju3 c1 0.1 f scl j1-1 j1 j1-2 j1-3 j1-4 j1-5 j1-6 j1-7 j1-8 j1-9 j1-10 j1-11 j1-12 j1-13 n.c. j1-14 j1-15 j1-16 j1-17 j1-18 j1-19 j1-20 gnd 1 scl 2 sda 3 ao 87 6 5 4 h w l gnd gnd 123 ju1 vdd vbus vbus sda sda scl r2 open sda h w l max5417l u1 n.c.n.c. n.c. n.c. n.c. n.c. figure 3. max5417l ev kit schematic downloaded from: http:///
evaluate: max5417_/max5418_/max5419_ max5417l evaluation kit/evaluation system 8 _______________________________________________________________________________________ figure 4. max5417l ev kit component placement guide component side figure 5. max5417l ev kit pc board layout?omponent side downloaded from: http:///
evaluate: max5417_/max5418_/max5419_ max5417l evaluation kit/evaluation system 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 _____________________ 9 2005 maxim integrated products printed usa is a registered trademark of maxim integrated products, inc. figure 6. max5417l ev kit pc board layout?older side downloaded from: http:///
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