| DS2890(3) | One-Wire File System | DS2890(3) |
NAME
DS2890 - 1-Wire Digital Potentiometer
SYNOPSIS
Variable resistance
2C [.]XXXXXXXXXXXX[XX][/[ chargepump | wiper |
See the file man3/standard_mini.3so.
]]
FAMILY CODE
2C
SPECIAL PROPERTIES
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
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
See the file man3/standard.3so.
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
See the file man3/description.3so.
DS2890
The 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
See the file man3/addressing.3so.
DATASHEET
http://pdfserv.maxim-ic.com/en/ds/DS2890.pdf
SEE ALSO
See the file man3/seealso.3so.
AVAILABILITY
http://www.owfs.org
AUTHOR
Paul Alfille (paul.alfille@gmail.com)
| 2003 | OWFS Manpage |