DS1844-100+ Maxim Integrated Products, DS1844-100+ Datasheet
DS1844-100+
Specifications of DS1844-100+
Related parts for DS1844-100+
DS1844-100+ Summary of contents
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... Operating Temperature Range - Industrial: -40°C to +85°C DESCRIPTION The DS1844 Quad Digital Potentiometer is a four-channel, digitally controlled linear potentiometer. Each potentiometer is comprised of 63 equi-resistive sections and has three terminals accessible to the user. These include the high side terminals, H wiper position on the resistor ladder is selected via an 8-bit register value. Communication and control of the device are supported by two types of serial interface ...
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... The DS1844 is a volatile device and will always power-up with the wiper positions set to mid-tap (position 32-decimal). The end-terminal H will have wiper position value 0-decimal. Because the DS1844 is a 64-position device only 6 bits of data are necessary to write a wiper’s value. However, communication with the DS1844 will require using a full 8 bits, with the remaining 2 bits specifying the potentiometer selected ...
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... The bus must be controlled by a master device which generates the serial clock (SCL), controls the bus access, and generates the START and STOP conditions. The DS1844 operates as a slave on the two-wire bus. Connections to the bus are made via the open-drain I/O lines SDA and SCL. ...
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... Slave transmitter mode: The 1 However, in this mode the direction bit will indicate that the transfer direction is reversed. Serial data is transmitted on SDA by the DS1844 while the serial clock is input on SCL. START and STOP conditions are recognized as the beginning and end of a serial transfer. ...
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... SLAVE ADDRESS A command/control byte is the 1 The command/control byte consists of a 4-bit control code. For the DS1844, this is set as 0101 binary for read/write operations. The next 3 bits of the command/ control byte are the device select bits or slave address (A2, A1, A0). They are used by the master device to select which of eight devices accessed ...
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... DS1844, potentiometer wiper data is transmitted to the DS1844 by the master device the case of the 5-wire serial protocol, a data byte for the DS1844 will contain potentiometer select data and wiper position value. The six least significant bits of data specify the wiper position value while the two most significant bits specify the potentiometer to be loaded ...
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ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature * This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the ...
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ANALOG RESISTOR CHARACTERISTICS (-40°C to +85°C; V PARAMETER SYMBOL End-to-End Resistor Tolerance Absolute Linearity Relative Linearity -3dB Cutoff frequency Temperature Coefficent 2-WIRE ADDRESSABLE INTERFACE AC ELECTRICAL CHARACTERISTICS PARAMETER SYMBOL Port Select Setup SCL Clock Frequency Bus Free Time Between STOP ...
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SERIAL INTERFACE AC ELECTRICAL CHARACTERISTICS PARAMETER Port Select Setup R/ W Setup Clock Frequency Width of CLK Pulse Data Setup Time Data Hold Time Progapation Delay Time High to Low Level Clock to Output RST High to Clock Input ...
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... For 5-wire control logic and V = +0.6V. 16. Absolute linearity is used to measure expected wiper voltage versus measured wiper voltage as determined by wiper position. The DS1844 is specified to provide an absolute linearity of ± 0.5 LSB. 17. Relative linearity is used to determine the change in wiper voltage between two adjacent wiper positions. The DS1844 is specified to provide a relative linearity of ± ...
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... DS1844 BLOCK DIAGRAM Figure 1 WIPER REGISTER CONFIGURATION Figure ...
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... SERIAL TIMING DIAGRAM Figure 3 (A), (B) (A) WRITING DATA TO THE DS1844 ...
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DATA TRANSFER OVERVIEW Figure 4 START COMMAND/CONTROL BYTE Figure 5 2-WIRE READ PROTOCOL Figure 6 2-WIRE WRITE PROTOCOLS Figure ...
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TIMING DIAGRAM Figure 8 DIGITAL OUTPUT LOAD Figure ...