数字电位器-IIC-MAX5432.pdf

General DescriptionThe MAX5432MAX5435 nonvolatile,linear-taper,digi-tal potentiometers perform the function of a mechanicalpotentiometer,but replace the mechanics with a simple2-wire serial interface.Each device performs the samefunction as a discrete potentiometer or a variable resis-tor and has 32 tap points.The MAX5432MAX5435 feature an internal,nonvolatile,electrically erasable programmable read-only memory(EEPROM)that returns the wiper to its previously storedposition at power-up.The fast-mode I2C-compatible serial interface allows communication at data rates up to400kbps,minimizing board space and reducing inter-connection complexity.Each device is available withone of four factory-preset I2C addresses(see theSelector Guide).Use the MAX5432MAX5435 in applications requiringdigitally controlled resistors.Two resistance values areavailable(50k and 100k)in a voltage-divider or vari-able resistor configuration.The nominal resistor temper-ature coefficient is 35ppm/C end-to-end,and only5ppm/C ratiometric,making the devices ideal forapplications requiring a low-temperature-coefficientvariable resistor such as low-drift,programmable-gainamplifier circuit configurations.The MAX5432/MAX5433 are available in a 3mm x 3mm 8-pin TDFN package and the MAX5434/MAX5435 are avail-able in a 6-pin thin SOT23 package.The MAX5432MAX5435 are specified over the extended(-40C to+85C)temperature range.ApplicationsMechanical Potentiometer ReplacementLow-Drift Programmable-Gain AmplifiersVolume ControlLiquid-Crystal Display(LCD)Screen AdjustmentFeatures Tiny 3mm x 3mm 8-Pin TDFN and 6-Pin ThinSOT23 Packages Power-On Recall of Wiper Position fromNonvolatile Memory 35ppm/C End-to-End Resistance TemperatureCoefficient 5ppm/C Ratiometric Temperature Coefficient 50k/100k Resistor Values Fast 400kbps I2C-Compatible Serial Interface 500nA(typ)Static Supply Current+2.7V to+5.25V Single-Supply Operation 32 Tap Positions 0.15 LSB INL(typ),0.15 LSB DNL(typ)MAX5432MAX543532-Tap,Nonvolatile,I2C,Linear,DigitalPotentiometers_ Maxim Integrated Products1Ordering Information19-3511;Rev 0;11/04For pricing,delivery,and ordering information,please contact Maxim/Dallas Direct!at 1-888-629-4642,or visit Maxims website at www.maxim-.PARTTEMP RANGEPIN-PACKAGEMAX5432LETA-40C to+85C8 TDFN-EP*MAX5432META*-40C to+85C8 TDFN-EP*MAX5433LETA-40C to+85C8 TDFN-EP*MAX5433META*-40C to+85C8 TDFN-EP*MAX5434LEZT-T-40C to+85C6 Thin SOT23-6MAX5434MEZT-T*-40C to+85C6 Thin SOT23-6MAX5434NEZT-T*-40C to+85C6 Thin SOT23-6MAX5434PEZT-T*-40C to+85C6 Thin SOT23-6MAX5435LEZT-T-40C to+85C6 Thin SOT23-6MAX5435MEZT-T*-40C to+85C6 Thin SOT23-6MAX5435NEZT-T*-40C to+85C6 Thin SOT23-6MAX5435PEZT-T*-40C to+85C6 Thin SOT23-6Purchase of I2C components from Maxim Integrated Products,Inc.,or one of its sublicensed Associated Companies,conveysa license under the Philips I2C Patent Rights to use these com-ponents in an I2C system,provided that the system conformsto the I2C Standard Specification as defined by Philips.Selector Guide appears at end of data sheet.*Future productcontact factory for availability.*EP=Exposed pad.TDFNTOP VIEWGNDSDASCL16L5WVDDSOT23234MAX5434MAX5435A0VDDSCL1287WLSDAGNDH3465MAX5432MAX5433Pin ConfigurationsMAX5432MAX543532-Tap,Nonvolatile,I2C,Linear,DigitalPotentiometers2_ABSOLUTE MAXIMUM RATINGSStresses beyond those listed under“Absolute Maximum Ratings”may cause permanent damage to the device.These are stress ratings only,and functionaloperation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied.Exposure toabsolute maximum rating conditions for extended periods may affect device reliability.VDDto GND.-0.3V to+6.0VSDA,SCL to GND.-0.3V to+6.0VA0,H,L,and W to GND.-0.3V to(VDD+0.3V)Maximum Continuous Current into H,L,and WMAX5432/MAX5434.1.3mAMAX5433/MAX5435.0.6mAInput/Output Latchup Immunity.50mAContinuous Power Dissipation(TA=+70C)6-Pin Thin SOT23(derate 9.1mW/C above+70C).727mW8-Pin TDFN(derate 24.4mW/C above+70C).1951mWOperating Temperature Range.-40C to+85CJunction Temperature.+150CStorage Temperature Range.-60C to+150CLead Temperature(soldering,10s).+300CELECTRICAL CHARACTERISTICS(VDD=+2.7V to+5.25V,VH=VDD,VL=GND,TA=-40C to+85C,unless otherwise noted.Typical values are at VDD=+5V,TA=+25C.)(Note 1)PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSDC PERFORMANCEResolution32TapsMAX5432/MAX543437.55062.5End-to-End ResistanceRH-LMAX5433/MAX543575100125kEnd-to-End ResistanceTemperature CoefficientTCR35ppm/CRatiometric ResistanceTemperature Coefficient5ppm/CVDD=5V0.150.5Variable resistor(Note 2)VDD=3V0.150.5VDD=5V0.150.5Integral NonlinearityINLVoltage-divider,MAX5432/MAX5433(Note 3)VDD=3V0.150.5LSBVDD=5V0.150.5Variable resistor(Note 2)VDD=3V0.150.5VDD=5V0.150.5Differential NonlinearityDNLVoltage-divider,MAX5432/MAX5433(Note 3)VDD=3V0.150.5LSBMAX5432,50k-0.5Full-Scale Error(Note 4)MAX5433,100k-0.5LSBMAX5432,50k+0.5Zero-Scale Error(Note 5)MAX5433,100k+0.5LSBWiper ResistanceRWMAX5432/MAX5433(Note 6)6101200DIGITAL INPUTSInput High VoltageVIH(Note 7)0.7 xVDDVInput Low VoltageVIL(Note 7)0.3 xVDDVInput Leakage CurrentILEAK1AInput Capacitance5pFMAX5432MAX543532-Tap,Nonvolatile,I2C,Linear,DigitalPotentiometers_3ELECTRICAL CHARACTERISTICS(continued)(VDD=+2.7V to+5.25V,VH=VDD,VL=GND,TA=-40C to+85C,unless otherwise noted.Typical values are at VDD=+5V,TA=+25C.)(Note 1)PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSDYNAMIC CHARACTERISTICSMAX5432/MAX5434500-3dB Bandwidth(Note 8)MAX5433/MAX5435250kHzMAX5432/MAX54340.5Wiper Settling Time(Note 9)MAX5433/MAX54351.0sNONVOLATILE MEMORY RELIABILITYData RetentionTA=+85C50YearsTA=+25C200,000EnduranceTA=+85C50,000StoresPOWER SUPPLYPower-Supply VoltageVDD2.705.25VStandby CurrentIDDDigital inputs=VDD or GND,TA=+25C0.52AProgramming CurrentDuring nonvolatile write;digital inputs=VDD or GND(Note 10)200900ANote 1:All devices are production tested at TA=+25C and are guaranteed by design and characterization for-40C TA+85C.TIMING CHARACTERISTICS(VDD=+2.7V to+5.25V,VH=VDD,VL=GND,TA=-40C to+85C,unless otherwise noted.Typical values are at VDD=+5V,TA=+25C.)(Figures 1 and 2)(Note 11)PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSSCL Clock FrequencyfSCL400kHzSetup Time for START ConditiontSU-STA0.6sHold Time for START ConditiontHD-STA0.6sCLK High TimetHIGH0.6sCLK Low TimetLOW1.3sData Setup TimetSU-DAT100nsData Hold TimetHD-DAT00.9sSDA,SCL Rise TimetR300nsSDA,SCL Fall TimetF300nsSetup Time for STOP ConditiontSU-STO0.6sBus Free Time Between STOPand START ConditiontBUF1.3sPulse Width of Spike SuppressedtSP50nsCapacitive Load for Each BusLineCB(Note 12)400pFNonvolatile Store TimeIdle time required after a nonvolatilememory write(Note 13)12msMAX5432MAX543532-Tap,Nonvolatile,I2C,Linear,DigitalPotentiometers4_TIMING CHARACTERISTICS(continued)(VDD=+2.7V to+5.25V,VH=VDD,VL=GND,TA=-40C to+85C,unless otherwise noted.Typical values are at VDD=+5V,TA=+25C.)(Figures 1 and 2)(Note 1)Typical Operating Characteristics(VDD=+5V,TA=+25C,unless otherwise noted.)00.30.90.61.21.5-4010-15356085STANDBY SUPPLY CURRENTvs.TEMPERATUREMAX543235 toc01TEMPERATURE(C)SUPPLY CURRENT(A)DIGITAL INPUTS=GND OR VDDVDD=5VVDD=3V00.20.60.40.81.02.53.53.04.04.55.05.5SUPPLY CURRENTvs.SUPPLY VOLTAGEMAX543235 toc02SUPPLY VOLTAGE(V)SUPPLY CURRENT(A)DIGITAL INPUTS=GND OR VDD02135SUPPLY CURRENTvs.DIGITAL INPUT VOLTAGEMAX543235 toc03DIGITAL INPUT VOLTAGE(V)SUPPLY CURRENT(A)10000.1110100VDD=5VVDD=3V4VVVWHH-31.VVVWLH-31.Note 2:The DNL and INL are measured with the potentiometer configured as a variable resistor.For the 3-terminal potentiometers(MAX5432/MAX5433),H is unconnected and L=GND.At VDD=5V,W is driven with a source current of 80A for the 50kconfiguration,and 40A for the 100k configuration.At VDD=3V,W is driven with a source current of 40A for the 50kconfiguration,and 20A for the 100k configuration.Note 3:The DNL and INL are measured with the potentiometer configured as a voltage-divider with H=VDDand L=GND(MAX5432/MAX5433 only).The wiper terminal is unloaded and measured with an ideal voltmeter.Note 4:Full-scale error is defined as Note 5:Zero-scale error is defined asNote 6:The wiper resistance is the worst value measured by injecting the currents given in Note 2 into W with L=GND.RW=(VW-VH)/IW.Note 7:The device draws current in excess of the specified supply current when the digital inputs are driven with voltages between(VDD-0.5V)and(GND+0.5V).See the Supply Current vs.Digital Input Voltage graph in the Typical Operating Characteristics.Note 8:Wiper is at midscale with a 10pF capacitive load.Potentiometer set to midscale,L=GND,an AC source is applied to H,and the output is measured as 3dB lower than the DC W/H value in dB.Note 9:This is measured from the STOP pulse to the time it takes the output to reach 50%of the output step size(divider mode).Itis measured with a maximum external capacitive load of 10pF.Note 10:The programming current exists only during NV writes(12ms typ).Note 11:Digital timing is guaranteed by design and characterization,and is not production tested.Note 12:An appropriate bus pullup resistance must be selected depending on board capacitance.Refer to the I2C-bus specifica-tion document linked to this web address: 13:The idle time begins from the initiation of the stop pulse.MAX5432MAX543532-Tap,Nonvolatile,I2C,Linear,DigitalPotentiometers_51.00.50-0.5-1.0-4010-15356085END-TO-END RESISTANCE%CHANGEvs.TEMPERATUREMAX543235 toc04TEMPERATURE(C)END-TO-END RESISTANCE CHANGE(%)50k1.00.50-0.5-1.0-4010-15356085END-TO-END RESISTANCE%CHANGEvs.TEMPERATUREMAX5432-35 toc05TEMPERATURE(C)END-TO-END RESISTANCE%CHANGE100k1s/divTAP-TO-TAP SWITCHING TRANSIENT(0 TO MIDSCALE,CL=10pF)VW1V/divSDA2V/divMAX543235 toc0650k10s/divWIPER TRANSIENT AT POWER-ONVW1V/divVDD2V/divMAX543235 toc0750kMIDSCALE WIPER RESPONSEvs.FREQUENCY(MAX5432)MAX5432 toc08FREQUENCY(kHz)GAIN(dB)100101-15-12-9-6-30-180.11000CW=10pFCW=33pF0100300200500600400700081241620242831WIPER RESISTANCE vs.TAP POSITION(MAX5432)MAX543235 toc09TAP POSITIONRESISTANCE()VDD=3V01003002005006004007000812416202428WIPER RESISTANCE vs.TAP POSITION(MAX5433)MAX5432-35 toc10TAP POSITIONRESISTANCE()VDD=3V310100300200500600400700081241620242831WIPER RESISTANCE vs.TAP POSITION(MAX5432)MAX543235 toc11TAP POSITIONRESISTANCE()VDD=5V01003002005006004007000812416202428WIPER RESISTANCE vs.TAP POSITION(MAX5433)MAX5432-35 toc12TAP POSITIONRESISTANCE()VDD=5V31Typical Operating Characteristics(continued)(VDD=+5V,TA=+25C,unless otherwise noted.)MAX5432MAX543532-Tap,Nonvolatile,I2C,Linear,DigitalPotentiometers6_Typical Operating Characteristics(continued)(VDD=+5V,TA=+25C,unless otherwise noted.)020104090301200812416202428W-TO-L RESISTANCE vs.TAP POSITIONMAX543235 toc13TAP POSITIONW-TO-L RESISTANCE(k)1101008060507050k100k31-0.5-0.3-0.4-0.1-0.20.100.20.40.30.5081241620242831RESISTANCE DNL vs.TAP POSITIONMAX543235 toc14TAP POSITIONRESISTANCE DNL(LSB)VARIABLE-RESISTOR MODEMAX5432/MAX5434-0.5-0.3-0.4-0.1-0.20.100.20.40.30.5081241620242831RESISTANCE INL vs.TAP POSITIONMAX543235 toc15TAP POSITIONRESISTANCE INL(LSB)VARIABLE-RESISTOR MODEMAX5432/MAX5434-0.5-0.3-0.4-0.1-0.20.100.20.40.30.5081241620242831RESISTANCE DNL vs.TAP POSITIONMAX543235 toc16TAP POSITIONRESISTANCE DNL(LSB)VOLTAGE-DIVIDER MODEMAX5432-0.5-0.3-0.4-0.1-0.20.100.20.40.30.5081241620242831RESISTANCE INL vs.TAP POSITIONMAX543235 toc17TAP POSITIONRESISTANCE INL(LSB)VOLTAGE-DIVIDER MODEMAX5432-0.5-0.3-0.4-0.1-0.20.100.20.40.30.50812416202428RESISTANCE DNL vs.TAP POSITIONMAX5432-35 toc18TAP POSITIONRESISTANCE DNL(LSB)VARIABLE-RESISTOR MODEMAX5433/MAX543531-0.5-0.3-0.4-0.1-0.20.100.20.40.30.50812416202428RESISTANCE INL vs.TAP POSITIONMAX5432-35 toc19TAP POSITIONRESISTANCE INL(LSB)VARIABLE-RESISTOR MODEMAX5433/MAX543531-0.5-0.3-0.4-0.1-0.20.100.20.40.30.50812416202428RESISTANCE DNL vs.TAP POSITIONMAX5432-35 toc20TAP POSITIONRESISTANCE DNL(LSB)VOLTAGE-DIVIDER MODEMAX543331-0.5-0.3-0.4-0.1-0.20.100.20.40.30.50812416202428RESISTANCE INL vs.TAP POSITIONMAX5432-35 toc21TAP POSITIONRESISTANCE INL(LSB)VOLTAGE-DIVIDER MODEMAX543331Detailed DescriptionThe MAX5432MAX5435 contain a resistor array with31 resistive elements.The MAX5432/MAX5434 providea total end-to-end resistance of 50k,and theMAX5433/MAX5435 provide an end-to-end resistanceof 100k.The MAX5432/MAX5433 allow access to the high,low,and wiper terminals for a standard voltage-divider con-figuration.Connect H,L,and W in any desired configu-ration as long as their voltages fall between GND andVDD.The MAX5434/MAX5435 are variable resistorswith H internally connected to the wiper.A simple 2-wire I2C-compatible serial interface movesthe wiper among the 32 tap points.Eight data bits,anaddress byte,and a control byte program the wiperposition.A nonvolatile memory stores and recalls thewiper position in the nonvolatile memory upon power-up.The nonvolatile memory is guaranteed for 200,000 wiperstore cycles and 50 years for wiper data retention.Digital InterfaceThe MAX5432MAX5435 feature an internal,nonvolatileEEPROM that returns the wiper to its previously storedposition at power-up.The shift register decodes thecontrol and address bits,routing the data to the propermemory registers.Write data to the volatile memoryregister to immediately update the wiper position,orwrite data to the nonvolatile register for storage.Writingto the nonvolatile register takes a minimum of 12ms.The volatile register retains data as long as the deviceis enabled and powered.Removing power clears thevolatile register.The nonvolatile register retains dataeven after power is removed.Upon power-up,thepower-on reset circuitry and internal oscillator controlthe transfer of data from the nonvolatile register to thevolatile register.Serial AddressingThe MAX5432MAX5435 operate as a slave that sendsand receives data through an I2C-and SMBus-com-patible 2-wire interface.The interface uses a serial dataaccess(SDA)line and a serial clock line(SCL)toachieve bidirectional communication betweenmaster(s)and slave(s).A master,typically a microcon-troller,initiates all data transfers to and from theMAX5432MAX5435,and generates the SCL clock thatsynchronizes the data transfer(Figure 1).SDA operates as both an input and an open-drain out-put.SDA requires a pullup resistor,typically 4.7k.SCL only operates as an input.SCL requires a pullupresistor(4.7k typ)if there are multiple masters on the2-wire interface,or if the master in a single-master sys-tem has an open-drain SCL output.Each transmission consists of a START(S)condition(Figure 3)sent by a master,followed by theMAX5432MAX5435 7-bit slave address plus the 8th bit(Figure 4),1 command byte(Figure 7)and 1 data byte,and finally a STOP(P)condition(Figure 3).Start and Stop ConditionsBoth SCL and SDA remain high when the interface isnot busy.A master signals the beginning of a transmis-sion with a START(S)condition by transitioning SDAfrom high to low while SCL is high.When the masterhas finished communicating with the slave,it issues aSTOP(P)condition by transitioning the SDA from low toMAX5432MAX543532-Tap,Nonvolatile,I2C,Linear