Rainbow-electronics DS2890 Instrukcja Użytkownika

1 of 28 040202FEATURES§ Single element 256-position linear taperpotentiometer§ Supports potentiometer terminal workingvoltages up to 11V§ Potentiom

DS289010 of 28FIGURE 11. DS2890 TO-92 CONFIGURATION BLOCK DIAGRAMFigure 12. VARIABLE RESISTOR MODELRHRWIPER

DS289011 of 28FIGURE 13. Typical Wiper Resistance vs Wiper Voltage at 25oC,Charge Pump OFF0.11101000246810Voltage Across Wiper (Volts)Wiper Resistanc

DS289012 of 28FIGURE 16. 1-WIRE CRC GENERATORRX2X1X0X8X7X6X5X4X38THSTAGE7THSTAGE6THSTAGE5THSTAGE4THSTAGE3RDSTAGE2NDSTAGE1STSTAGESINPUT DATAPolynomial

DS289013 of 28READ CONTROL REGISTER [AAH]The Read Control Register command is used to obtain both the Control Register and potentiometerFeature Regist

DS289014 of 281-WIRE BUS SYSTEMThe 1-Wire bus is a system, which has a single bus master and one or more slaves. In all instances theDS2890 is a slave

DS289015 of 28FIGURE 18. BUS MASTER WITH DS2480B DRIVERVDDPOLRXDTXDVPP1-WGNDNCDS2480B+5Vto 1-WIRE connectionof DS2890serial inserial outHOST CPUseria

DS289016 of 28SEARCH ROM [F0H]When a multi-drop system is initially brought up, the bus master might not know the number of deviceson the 1-Wire bus o

DS289017 of 28RESUME COMMAND [A5H]In a typical application the DS2890 may be accessed several times to complete a control adjustment. In amulti-drop e

DS289018 of 28MASTER MODE DATA (LSB FIRST) COMMENTSTX C3h Issue Wiper Increment CommandRX <data byte> Read new wiper positionTX C3h Issue Wiper

DS289019 of 28FIGURE 19. INITIALIZATION PROCEDURE “RESET AND PRESENCEPULSES”RESISTORMASTERDS2890MASTER RX "PRESENCE PULSE"REGULAR SPEED OVE

DS28902 of 28PIN DESCRIPTIONSIGNALNAME TYPE FUNCTION1-WIRE I/O 1-Wire bus interface. Open drain, requires external pull-up resistor. Range:2.8V – 6.0

DS289020 of 28b) Write-zero Time Slot15µsRESISTORMASTER(OD: 2µs)DS289060µstLOW0Sampling Window(OD: 6µs)REGULAR SPEEDOVERDRIVE SPEED60 µs £ tLOW0 <

DS289021 of 28FIGURE 21. POTENTIOMETER FUNCTION COMMAND FLOW

DS289022 of 28FIGURE 22. POTENTIOMETER FUNCTION COMMAND FLOW (CONTINUED)

DS289023 of 28FIGURE 23. ROM FUNCTION COMMAND FLOW

DS289024 of 28FIGURE 24. ROM FUNCTION COMMAND FLOW (CONTINUED)

DS289025 of 28ELECTRICAL CHARACTERISTICSABSOLUTE MAXIMUM RATINGSVoltage on RH, RL, WIPER Relative to Ground -0.5V to +11.0VVoltage on Other Pins Relat

DS289026 of 28Notes:1. Voltage is referenced to ground.2. Valid at 25oC only.3. Wiper resistance is a function of operating characteristics. See s

DS289027 of 28AC ELECTRICAL CHARACTERISTICS - REGULAR 1-WIRE SPEED2.8V £ VPUP £ 6.0V, -40°C £ TA £ +85°CPARAMETER SYMBOL MIN TYP MAX UNITS NOTESTime S

DS289028 of 28AC ELECTRICAL CHARACTERISTICS - OVERDRIVE 1-WIRE SPEED2.8V £ VPUP £ 6.0V, -40°C £ TA £ +85°CPARAMETER SYMBOL MIN TYP MAX UNITS NOTESReco

DS28903 of 28OPERATIONThe DS2890 is a single element digital potentiometer; a block diagram of the device is shown in Figure 1.The device has a total

DS28904 of 28FIGURE 2. 1-Wire Command Hierarchical StructureDATA I/O BIT ORDERAll data is read and written least significant bit (LSB) first.POTENTIO

DS28905 of 28FIGURE 3. 1-WIRE POTENTIOMETER FEATURE REGISTERFeature Register Bit Encodingb7 b6 b5 b4 b3 b2 b1 b0PR NWP NP WSV PCFeature Register Bit

DS28906 of 28FIGURE 4. POTENTIOMETER CONTROL REGISTERControl Register Bit Encodingb7 b6 b5 b4 b3 b2 b1 b0XCPC X XWNWNControl Register Bit Definitions

DS28907 of 28POWER and CONFIGURATION CONSIDERATIONS1-Wire devices can typically derive operating power entirely from the 1-Wire bus by storing energy

DS28908 of 28Figure 6. Variable Resistor Configurations(TO92 Package)RHWIPERRLVDD1-WIREGND2.8V to 6.0VorNo Connect2.8V to 6.0VBusMasterRH1-WIREGND2.8

DS28909 of 28FIGURE 10. Typical Wiper Resistance vs Wiper Voltage at 25oC,Charge Pump ON10010000.1 5.5 11Voltage Across Wiper (V)Wiper Resistance (oh