DS2890(3) One-Wire File System DS2890(3)

# [NAME](#NAME)

**DS2890** - 1-Wire Digital Potentiometer

# [SYNOPSIS](#SYNOPSIS)

Variable resistance

**2C** \[.]XXXXXXXXXXXX\[XX][/[ **chargepump** | **wiper** |

See the file man3/standard\_mini.3so.

]]

# [FAMILY CODE](#FAMILY_CODE)

*2C*

# [SPECIAL PROPERTIES](#SPECIAL_PROPERTIES)

## [chargepump](#chargepump)

*read-write, yes-no*  
State of the *chargepump* in the chip (0 = off 1 = on). Only available if external power is available (hence not in the TO-92 packaging) at pin Vdd.  
When *chargepump* is on, the *wiper* resistance will range between Rh and Rl relatively linearly.  
When *chargepump* is off, the *wiper* resistance (to ground) will range relatively linearly (to 100kOhms).

## [wiper](#wiper)

*read-write, unsigned integer*  
Value of the variable element, 0 to 255. The actual interpretation of *wiper* depands on the *chargepump* state, but in general 0 is low and 255 is high.

# [STANDARD PROPERTIES](#STANDARD_PROPERTIES)

See the file man3/standard.3so.

# [ALARMS](#ALARMS)

The device condition that will cause individual **DS2890s** to participate in a Conditional Search is a wiper position located at the power-on default setting (00h). This feature enables the bus master to easily determine whether a potentiometer has gone through a power-on reset and needs to be re-configured with a required wiper position setting.

# [DESCRIPTION](#DESCRIPTION)

See the file man3/description.3so.

## [DS2890](#DS2890)

The [**D2890 (3)**](/man/os/owfs/D2890.3) allows variable resistance under 1-wire control. Possible uses are analog feedback mechanisms (sound pitch, light level).

Although there are provisions in the datasheet for different **DS2890** configurations (non-linear wiper ranges, multiple wipers, different resistance scales) non are in production. To simplify implementation, this driver assumes the standard **DS2890** design.

# [ADDRESSING](#ADDRESSING)

See the file man3/addressing.3so.

# [DATASHEET](#DATASHEET)

http://pdfserv.maxim-ic.com/en/ds/DS2890.pdf

# [SEE ALSO](#SEE_ALSO)

See the file man3/seealso.3so.

# [AVAILABILITY](#AVAILABILITY)

http://www.owfs.org

# [AUTHOR](#AUTHOR)

Paul Alfille (paul.alfille@gmail.com)

2003 OWFS Manpage

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Document: DS2890(3) from owfs 3.2.4-r10 (Chainguard OS)
Source: https://github.com/owfs/owfs