DS2890

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PIN DESCRIPTION

SIGNAL

NAME

TYPE

FUNCTION

1-WIRE

I/O

1-Wire bus interface. Open drain, requires external pull-up resistor. Range:

2.8V – 6.0V. See HARDWARE CONFIGURATION for pull-up resistor

recommendations.

RH

I/O

High end terminal of potentiometer resistor element. Range: 0V – 11.0V.

levels applied to the other potentiometer terminals.

RL

I/O

Low end terminal of potentiometer resistor element. Range: 0V – 11.0V.

levels applied to the other potentiometer terminals.

WIPER

I/O

Potentiometer wiper terminal. Range 0V – 11.0V. Range independent of

potentiometer terminals.

PWR

Auxiliary power supply input. Range: 2.8V – 6.0V

GND

PWR

Ground

DESCRIPTION

The DS2890 is a linear taper digitally controlled potentiometer with 256 wiper positions.

Device

operation, including wiper position, is controlled over the single contact 1-Wire bus for the ultimate in

electrical interface simplicity.

With a wide 0–11 volt working voltage range for the potentiometer

terminals, the DS2890 is ideal for a broad range of industrial and control applications. Potentiometer

terminal voltage is independent of device supply voltage as well as the voltage applied to the other

potentiometer terminals. Communication with the DS2890 follows the standard Dallas Semiconductor

1-Wire protocol and can be accomplished with minimal hardware such as a single port pin of a

microcontroller.

Multiple DS2890 devices can reside on a common 1-Wire bus and be operated

independently of each other. Each DS2890 has its own unalterable 64-bit ROM registration number that

is factory lasered into the chip. The registration number guarantees unique identification for absolute

traceability and is used to address the device in a multi-drop 1-Wire Network environment. The DS2890

will respond to a 1-Wire Conditional Search command if the potentiometer wiper is set at the power-on

default position. 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. The

DS2890 supports two power modes: 1-Wire only mode in which device power is supplied parasitically