1 of 10 features ? s ingle 100 - position taper pot entiometer ? nonvolatile (nv) on - demand wiper stora ge ? operates from 3v or 5v s upplies ? up/ down, increment - controlled in terface ? available in 8 - p in (300 mil s ) dip, 8 - p in (150 mil s ) so, and 8- p in (118 m il s ) sop ? - 40 c to +85 c operating temperature range ? standard resistance values: ? ds1804 - 010: 10k ? ? ds1804 - 050: 50k ? ? ds1804 - 100: 100k ? pin a ssignment pin desc r iption h - high - terminal of potentiometer l - low - t erminal of potentiometer w - wiper of potentiometer v cc - 3v or 5v power supply cs - chip select u/ d - up/down control inc - increment/decrement wiper control gnd - ground description the ds1804 nv trimmer potentiometer is a nonvolatile digital potentiometer that has 100 positions. the device provides an ideal method for low - cost trimming applications using a cpu or manual control input with minimal external circuitry. wiper position of the ds1804 can be stored in eeprom memory on demand. the device?s wiper position is manipulated by a three - terminal port that provides an increment/ decrement counter controlled interface. this port consists of the control inputs cs , inc , and u/ d . the ds1804 is available in three resistor grades, which include a 10k ? , 50k ? , and 100k ? . the device is provided in an industrial temperature grade. additionally, the ds1804 will operate from 3v or 5v supplies and is ideal for portable application requirements. three packaging options are available and include the 8 - pin (300 mil s ) dip, 8 - pin (150 mil s ) so, and 8- pin (118 mils ) sop . ds1804 n onvolatile trimmer potentiometer 19- 5876; rev 6/11 inc 1 8 v cc u/d 2 7 cs h 3 6 l gnd 4 5 w dip (300 mil s ) so (150 mil s ) sop (118 mil s )
ds1804 2 of 10 operation the ds1804 is a single nonvolatile potentiometer. the device has a total of 100 tap - points including the l - and h - terminals. a total of 99 resistive segments exist between the l - and h - terminals. these tap - points are accessible to the w - terminal, whose position is controlled via a three - terminal control port. a block diagram of the ds1804 is shown in figure 1. the three - terminal port of the ds1804 provides a n increment/decrement interface which is activated via a chip - select input. this interface consists of the input signals cs , inc , and u/ d . these input signals control a 7 - bit up/down counter. t he output of the 7 - bit up/down counter controls a 1 of 100 decoder to select wiper position. additionally, this interface provides for a wiper storage operation using the cs and inc input control pins. the timing d iagram for the three - terminal interface control is shown in figure 2. pin descriptions v cc - power supply. the ds1804 will support supply voltages ranging from +2.7v to +5.5v. gnd - ground. h - high - terminal potentiometer. this is the high terminal of the potentiometer. it is not required that this terminal be connected to a potential greater than the l - terminal. voltage applied to the h - terminal cannot exceed the power - supply voltage, v cc , or go below ground. l - low - terminal potentiometer. this is the low terminal of the potentiometer. it is not required that this terminal be connected to a potential less than the h - terminal. voltage applied to the l - terminal cannot exceed the power - supply voltage, v cc , or go below ground. w - wiper of the potenti ometer. this pin is the wiper of the potentiometer. its position on the resistor array is controlled by the three - terminal control port. voltage applied to the wiper cannot exceed the power - supply voltage, v cc , or go below ground. cs - chip select. the cs input is used to activate the control port of the ds1804. this input is active low. when in a high - state, activity on the inc and u/ d port pins will not affect or change wiper position. inc - wiper movement control. this input provides for wiper position changes when the cs pin is low. wiper position changes of the w - terminal will occur one position per high - to - low transition of th is input signal. position changes will not occur if the cs pin is in a high state. u/ d - up/down control. this input sets the direction of wiper movement. when in a high state and cs is low, any high - to - low transition on inc will cause a one position movement of the wiper towards the h - terminal. when in a low state and cs is low, any high - to - low transitions on inc will cause the pos ition of the wiper to move towards the l - terminal.
ds1804 3 of 10 ds1804 block diagram figure 1 power - up/power - down conditions on power - up, the ds1804 will load the value of eeprom memory into the wiper position register (or 1 of 100 decoder ). the value of this register can then be set to another wiper position if desired, by using the three - terminal control port. on power - up, wiper position will be loaded within a maximum time period of 500 s once the power - supply is stable. additionally, th e three - terminal interface port will be active after 50ms. on power - down, the wiper position register data will be lost. on the next device power - up, the value of eeprom memory will be loaded into the wiper position register. on shipment from the facto ry, maxim integrated products does not guarantee a specified eeprom memory value. this value should be set by the customer as needed. nonvolatile wiper storage wiper position of the ds1804 can be stored using the inc and cs inputs. storage of the wiper position takes place whenever the cs input transitions from low - to - high while the inc is high. once this condition has occurred the value of the current wip er position will be written to eeprom memory. the ds1804 is specified to accept 50,000 writes to eeprom over 0c to 70oc before a wear - out condition. after wear - out the ds1804 will still function and wiper position can be changed during powered conditions using the three - terminal control port. however, on power - up the wiper - position will be indeterminate. one - time programmability (otp) the ds1804 can be easily used as an otp device. the user of the ds1804 can trim the desired value of the wiper position a nd set this position for storage as described above. any activity through the three - terminal port can then be prevented by connecting the cs input pin to v cc . also, an otp application does not adversely affect the number of times eepro m is written, since eeprom will only be loaded and not written during a power - up or power - down condition. on power - up, the ds1804 will load the current value of eeprom memory into the wiper position register.
ds1804 4 of 10 absolute maximum ratings voltage on any pin relative to ground - 1.0v to + 6 .0v operating temperature range - 40c to +85c storage temperature range - 55c to +125c lead temperature (soldering, 10s) +300 c soldering temperature (reflow) +260c this is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. exposure to absolute maximum rating conditions for extended periods of time may affect reliability. recommended dc operating conditions ( t a = - 40 c to +85c , unless otherwise noted. ) parameter symbol min typ max units notes supply vo ltage v cc +2.7 5.5 v 1 input logic 1 v ih 2.0 v cc + 0. 3 v 1, 2 input logic 0 v il - 0. 3 +0.8 +0.6 v 1, 15 resistor inputs l, h, w v gnd - 0. 2 v cc + 0. 2 v 1, 3 dc electrical characteristics ( v cc = 2.7v to 5.5v, t a = - 40 c to +85 c , unless otherwise noted. ) parameter symbol min typ max units notes supply current i cc 400 a 4 input leakage i li - 1 +1 a wiper resistance r w 400 1000 ? wiper current i w 1 ma standby current: 3v 5v i stby 10 20 48 a a 5 wiper load time t wlt 500 s 6 power - up time t pu 50 ms 14
ds1804 5 of 10 analog resistor characteristics ( v cc = 2.7v to 5.5v, t a = - 40 c to +85 c , unless otherwise noted. ) parameter symbol min typ max units n otes end - to - end resistor tolerance - 20 +20 % 8 absolute linearity 0.6 lsb 9 relative linearity 0.25 lsb 10 - 3db cutoff frequency f cutoff mhz 11 temperature coefficient 750 ppm/ c capacitance ( v cc = 2.7v to 5.5v, t a = +25c , unless otherwise noted. ) parameter symbol min typ max units notes input capacitance c in 5 pf 12 output capacitance c out 7 pf 12 ac electrical characteristics ( v cc = 2.7v to 5.5v, t a = - 40 c to +85 c , unless otherwise noted. ) parameter symbol min typ max units notes cs to inc setup t ci 50 ns 13 u/ d to inc setup t di 100 ns 13 inc low period t il 50 ns 13 inc high period t ih 100 ns 13 inc inactive to cs inactive t ic 500 ns 13 cs deselect time t cph 100 ns 13 wiper change to inc low t iw 200 ns 13 inc rise and fall times t r , t f 500 s 13 inc low to cs inactive t ik 50 ns 16 wiper storage time t wst 10 ms 13, 17
ds1804 6 of 10 notes: 1) all voltages are referenced to ground. 2) valid for v cc = 5v only. 3) resistor input voltages cannot go below ground or exceed v cc by the amounts as shown in the table. 4) maximum current specifications are based on the clock rate of inc input. this specification represents the curr ent required when changing the wiper position. 5) standby current levels apply when all inputs are driven to appropriate supply levels. cs , inc , u/ d = v cc . 6) wiper load time is specified as the time req uired for the ds1804 to load the wiper position with the contents of nonvolatile memory once v cc has reached a stable operating voltage equal to or greater than 2.7v. 7) the ds1804 is available in three resistor values. these include the ds1804 - 010, 10k ? ; th e ds1804 - 050, 50k ? ; and the ds1804 - 100, 100k ? . 8) valid at t a = + 25c only. 9) absolute linearity is used to compare measured wiper voltage versus expected wiper voltage as determined by wiper position. the ds1804 is specified to provide an absolute linearity of 0. 60 lsb. 10) relative linearity is used to determined the change in voltage between successive tap positions. the ds1804 is specified to provide a relative linearity specification of 0.25 lsb. 11) - 3db cutoff frequency characteristics for the ds1804 depend on po tentiometer total resistance. ds1804 - 010, 1mhz; ds1804 - 050, 200 khz; and ds1804 - 100, 100 khz. 12) capacitance values apply at t a = + 25c. 13) see figure 2. 14) power - up time is specified as the time required before the three - terminal control becomes active after a stable power supply level has been reached. 15) at v cc = 2.7v, v il = 0.8v. 16) the inc low to cs inactive is specified to be 50ns minimum. this is the transition condition which allows the ds1804 three - terminal port to become i nactive without writing the eeprom memory of the part. 17) wiper storage time, t wst , is the time require for the ds1804 to write eeprom memory for storage of a new wiper position. the maximum time required to accomplish this task is specified at 10ms.
ds1804 7 of 10 three - terminal interface timing diagram figure 2 ordering information part version (k ?) temp range pin - package ds1804 - 010+ 10 - 40c to +85c 8 dip (300 mils ) ds1804 - 050+ 50 - 40c to +85c 8 dip (300 mils ) ds1804 - 100+ 100 - 40c to +85c 8 dip (300 mils ) ds1804z - 010+ 10 - 40c to +85c 8 so (150 mils ) ds1804z - 050+ 50 - 40c to +85c 8 so (150 mils ) ds1804z - 100+ 100 - 40c to +85c 8 so (150 mils ) ds1804u - 010+ 10 - 40c to +85c 8 sop (118 mils ) ds1804u - 050+ 50 - 40c to +85c 8 sop (118 mils ) ds1804u - 100+ 100 - 40c to +85c 8 sop (118 mils ) + denotes a lead (pb) /rohs - compliant package.
ds1804 8 of 10 branding information figure 3 d s1804m yywwrv ###xx 1804 rv nnn top brand bottom brand 8-pin dip 8-pin soic 8-pin usop cccccc yyww ###xx ds1804 brand codes code description values nnn pot size (dip/usop) 010 10k ohm 050 50k ohm 100 100k ohm m pot size (soic) x 10k ohm l 50k ohm c 100k ohm yyww date code. it identifies the year and work week the device was assembled eg. 0035 is the 35th work week of 2000 rv die revision generally this is a letter followed by a number (eg. b2) ###xx lot code cccccc country of assembly cccccc ds1804-nnn yywwrv ###xx
ds1804 9 of 10 package information for the latest package outline information and land patterns (footprints), go to www.maxim - ic.com/packages . note that a ?+?, ?#?, or ? - ? in the package code i ndicates rohs status only. package drawings may show a different suffix character, but the drawing pertains to the package regardless of rohs status. package type package code outline no. land pattern no. 8 dip p8+2 21- 0043 ? 8 so s8+2 21- 0041 90- 0096 8 sop u8+3 21- 0036 90- 0092
ds1804 10 of 10 maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circu it 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 ? 2011 maxim integrated products maxim is a registered trademark of maxim integrated products, inc. revision history revision date description pages changed 6/11 removed the flip chip package option 1, 7 updated the soldering temperatur e information and added lead temperature information in the absolute maximum ratings section 4 changed v ih(max) from v cc + 0.5v to v cc + 0.3v, changed v il(min) from -0.5v to -0.3v, changed the resi stor inputs min from gnd - 0.5v to v gnd - 0.2v and max from v cc + 0.5v to v cc + 0.2v in the recommended dc operating conditions table 4 updated the ordering information table to include lead-free options 7 added the package information table 9
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