The mcp41xxx is a singlechannel digital potentiometer. The difference is a digital potentiometer ic is controlled by software, while a regular potentiometer is controlled manually by a person. And8414 everything you wanted to know about digital. Maxim design support technical documents tutorials digital potentiometers app 1828 keywords. Know about digital potentiometer pot abstract the digital pot is a mixed signal device. Functional block diagram of the max5160 digital pot. Epm 3790 digital potentiometer is a compact solution for startstopfrowardreverse push buttons and indicator, with set speed on the fly. The analog portion of the device is the threeterminal analog component called potentiometer. The max5160max5161 lineartaper digital potentiome ters perform the same function as a mechanical poten tiometer or a variable resistor.
How can i obtain digital potentiometer technical support. Configured as a voltage divider, this ic provides an output of 32 discrete voltage steps between its minimum and maximum settings 0v. How to use digital potentiometers to control light and. All of its outputs are unconnected except for the mostsignificantbit pin. A digital potentiometer also known as digipot, is similar to a standard analogue potentiometer, which is a variable resistor except the digital potentiometer has an integrated chip ic that accepts a signal input rather than. Microchip mcp41xxx digital potentiometer implementation in opamp audio amplifier circuit and interfacing to microchip pic18f4520 microcontroller ahmad alqudaihi april 4th, 2010 abstract the mcp41xxx is a singlechannel digital potentiometer. Dnl max inl potentiometer dnl potentiometer inl clock freq max. Learn more about digital potentiometers from texas instruments, including single and dual channel digitpots for i2c and spi interfaces. Lineartaper digital potentiometers can be used in simple voltage divider configurations to provide these nonlinear transfer functions. Max5387 dual 256tap volatile lowvoltage linear taper. Features 32position linear taper potentiometer nonvolatile eeprom wiper storage.
Logic inputs cs, ud, and incdetermine the position of the wiper. The serial interface options allow you to easily integrate the device into your application. How to use digital potentiometers to control light and sound. Using arduino s i2c wire library, the digital pot will step through 64 levels of resistance, fading an led. The max5160max5161 lineartaper digital potentiometers perform the same function as a mechanical potentiometer or a variable resistor. For the max5160, linearity is defined in terms of h to l codedependent resistance. Just like a regular potentiometer, a digital pot ic comes in all different values of resistance.
Digital potentiometer u1 and comparator u3 form a digital trackandhold. A digital potentiometer is a digitallycontrolled electronic component that mimics the analog. Using arduino s i2c wire library, the digital pot will step through 64 levels of resistance, fading an led the i2c protocol involves using two lines to send and receive data. The digital pot can be used as a threeterminal resistive divider or as a twoterminal variable resistor. The specific digital potentiometer we will use in this circuit is the mcp41 ic. This solidstate industrial potentiometer simulates an equivalent mechanical potentiometer, and fits in the same space. Since the digitally controlled potentiometer is a digital device, it must have some kind of memory right. Digital pots bring variability and programmability to a wide variety of applications including control, parameter adjustments, and signal processing.
The ad5206 is spicompatible,and to command it, you send two bytes. Single and dualchannel digital potentiometers digipots for your design needs. The mcp41 digital potentiometer communicates via the serial peripheral interface bus, or spi bus. They are lineartaper digital potentiometers perform the same function as a mechanical potentiometer or a variable resistor. One of the most common types of variable resistors is the potentiometer. The small package size, low supply operating voltage. They consist of a fixed resistor and a wiper contact with 32 tap points that are digitally controlled by three lines for the 8pin max5160 or by two lines for the 6pin max5161. Digital potentiometers are a three terminal device, two fixed end terminals and one wiper terminal which is used to vary the resistance. They consist of a fixed resistor and a wiper contact with 32 tap points that are digitally controlled by three lines for the 8pin max5160 or by two lines for the 6. The digital portion contains the interface, control, and registers associated with the potentiometer. The selected step on the ladder determines the resistance ratio of the. Ironhorse gsdadp digital potentiometer general information the gsdadp digital potentiometer is a compact, microprocessorbased unit capable of being either field or factory configured for a number of industrial userinterface control signal needs. Thirtytwo tap points areaccessible to the wiper along the resistor stringbetween h and l. Cat512051215122 lineartaper digital pots perform the same function as a mechanical potentiometer or a variable resistor.
Back of the digital potentiometer additional board. Max5160 lowpower digital potentiometers maxim integrated. Ti home data converters digital potentiometers digipots data converters. How to build a digital potentiometer circuit with a mcp41. The basis of the circuit is a modified schmitttrigger relaxation oscillator controlled by max5160 digital potentiometer. Digital potentiometer u1 and comparator u3 form a digital trackandhold circuit, in which u1 adjusts its internal voltage divider to make v wiper track v in. Maxim design support technical documents application. Pdf coman838 an838, app838, appnote838, logarithmic potentiometer 50k simple digital volume control circuit digital potentiometers excel formula max5467 potentiometers 10k log max5464 max5463 max5462 max5460. Microchip offers digital potentiometer devices with typical endtoend resistances of 2. You can use a digital potentiometer in two ways in an analog circuit. Note that the max5160 has a powerup reset that sets the wiper position to midscale, enabling the two digital pots to. Related parts max5160 lowpower digital potentiometers max5161 lowpower digital. Ac and dc motors in modern industrial systems are often controlled via programmable logic.
They consist of a fixed resistor and a wiper contact with 32 tap points that are digitally controlled by three lines for the or by two lines for the 6pin max5161. The gsdadp allows the user to adjust the displayed value via the frontpanel push buttons. Digital pot control this example controls an analog devices ad5206 digital potentiometer. Digital potentiometer is also called digital pot in short. Unlike mechanical pots, digital pots can be controlled dynamically in active control applications. Audio gain control using digital potentiometers tutorial. Potentiometer or pots, are three terminal devices, used to vary the resistance in a circuit. It is a kind of mixed signal ic, which is able to dynamically change the internal resistors through mcu like arduino. Digital potentiometers design guide supporting digital potentiometer applications, including. Please view our selection of digital potentiometer ics below. The mcp41xxx and mcp42xxx devices are 256 position, digital potentiometers available in 10k.
Note that the max5160 has a powerup reset that sets the wiper position. The integrated eeprom option allows you to save digital potentiometer settings at powerdown and restore to its original value and powerup. Unlike the majority of the digital potentiometers in. Digitally controled 500k resistor all about circuits. Mostly the digipots use volatile memory, meaning that when powered down, they will lose the prior information and will reset to a default value when powered up. Potentiometer circuits electronics tutorial and schematics. A digital potentiometer is built either from a resistor ladder integrated circuit or a digital toanalog converter although a resistor ladder construction is the more common. The digital potentiometer is based on the cmos string dac.
Pdf an1291 ad5227 ad5227 an120520315 ad512 op amp adr512. When the digital potentiometer board is connected to easypic, lv18f, easylv18f, easy2433 and bigpic development systems, the following switches on the dip switch sw1 should be set to the on position. Maxim design support technical documents application notes digital potentiometers app 843 keywords. The key to this circuit is a lowpower digital potentiometer ic, 100k. Normally lurking unseen inside stereo systems, the digital potentiometer needs no adjustment, because it adjusts itself. This is done by making use of a resistor ladder, a string of small resistors in series. This example shows how to control a analog devices ad5171 digital potentiometer which communicates via the i2c synchronous serial protocol. The most commonly available digital pots are effectively linear pots, i.
Its fluctuating resistance can change the color or brightness of a light, the loudness or frequency of a sound, or any other parameters that depend on voltage and current. A digital potentiometer can be, the analog devices website. Maxim integrated digital potentiometer ics are available at mouser electronics. The binary digital data is converted to analog by a r2r resistor network. Other ways of communicating are through the i 2 c bus and the serial uart bus the spi us was originally created by motorola and is a fullduplex serial communication standard that enables simultaneous bidirectional communication between a master device and one or more slave devices. Do you want to add a small motor to the 500k pot you have, or alter the circuit to use the 10k digital pot you can buy, or what. The biggest digital potentiometer that i could find was a 10k one like reply. The variable resistor offers a completely programmable value of resistance, between the a terminal and the wiper or.
Digital potentiometer additional board mcp41010 circuit is a digital potentiometer connectors used to connect the additional board to a controlled device figure 2. Digital potentiometer programs and stabilizes voltage reference. For the following examples of these types of transfer functions, the 50k. Protocolspecific digipots for i2c, spi and parallel interfaces. Max5160 digital potentiometers maxim three resistance values are available for each part type.
Singledual digital potentiometer with spi interface microchip. The max5160 max5161 lineartaper digital potentiometers perform the same function as a mechanical potentiometer or a variable resistor. A reasonably constant dbperstep law is desirable in audio volume. Each channels pins are labeled a connect this to voltage w this is the pots wiper, which changes when you set it b connect this to ground. Digital potentiometer ics are available at mouser electronics from industry leading manufacturers. This is why i chose a digital potentiometer that has 128 taps, so we could make it step up and down with an 8bit timer. A digital potentiometer also known as digital resistor has the same function as a normal potentiometer but instead of mechanical action it uses digital signals and switches. Digital potentiometer ad5242 the cascaded counters counts the clock you generate by key press to count updown in binary. Digital potentiometers convert voltage to resistance.
Digital potentiometers digipots 9 digital toanalog converters dacs 334 highspeed dacs 10msps 72 precision dacs digital xray. Mcp4xxxx digital potentiometer cross reference guide. Digital potentiometers design guide microchip technology. Digital potentiometer ics digital pot 128 step spi sngl ch 5 pieces by microchip technology only 3 left in stock order soon. There are three different models of this device, mcp41010, mcp41050, and mcp41100. A listing of scillcs productpatent coverage may be accessed at.
Ad5207 2channel 256position digital potentiometer datasheet pdf technical report. It can be applied to applications such as led dc dimming, linear stable voltage source, oscillator, low pass filter or differential amplifier. The final circuit and schematic are shown in figure e, using a 74hc4520 timer chip, which contains two 4bit counters, chained together. Scales from 1999 to 9999 with moveable decimal point.