Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsData collecting ICsData acquisition IC - Digital potentiometer linear Non-permanent TSSOP 20

1 of 8 102199

FEATURES

§ Six digitally controlled 64-position

potentiometers

§ 3-wire serial port provides for reading and

setting each potentiometer

§ Devices can be cascaded for single processor

multi-device control

§ Standard resistance values:

- DS1806-010 10 kΩ

- DS1806-050 50 kΩ

- DS1806-100 100 kΩ

§ Operating Temperature Range:

- Industrial temperature: -40°C to +85°C

PIN DESCIPTION

- 3V or 5V Supply

RST - Serial Port Reset Input

- Serial Port Data Input

CLK - Serial Port Clock Input

OUT

- Cascade Data Output

H1 - H6 - High End terminal of Pot

W1 - W6 - Wiper Terminal of Pot

GND - Ground

L1-3 - Low Terminal Pots 1 through 3

L4-6 - Low Terminal Pots 4 through 6

PIN ASSIGNMENT

DESCRIPTION

The DS1806 Digital Sextet Potentiometer is a six-channel, digitally controlled, solid-state linear

potentiometer. Each potentiometer is comprised of 63 equiresistive sections as illustrated in the block

diagram of Figure 1. Each potentiometer has three terminals accessible to the user. These include the high

side terminals, H

, the wiper terminals, W

, and the low-end terminals, L1-3 and L4-6. Potentiometers 1

through 3 share the same low-end terminal L1-3; likewise, potentiometers 4 through 6 share the low-end

terminal L4-6.

Each wiper’s position is selected via an 8-bit register value. Communication and control of the device is

accomplished via a 3-wire serial port interface. This interface in conjunction with a cascade output allows

the value of the device wiper settings to be read.

DS1806

Digital Sextet Potentiometer

www.dalsemi.com

W1 1 20 V

W2 2 19 H1

L1-3 3 18 H2

W3 4 17 H3

W4 5 16 H4

L4-6 6 15 H5

W6 7 14 W5

RST 8 13 H6

CLK 9 12 D

GND 10 11 C

OUT

DS1806 20-Pin DIP (300-mil)

DS1806S 20-Pin SOIC (300-mil)

DS1806E 20-Pin TSSOP (173-mil)

See Mech. Drawings Section

Summary of content (8 pages)

PAGE 1
DS1806 Digital Sextet Potentiometer www.dalsemi.
PAGE 2
DS1806 For multiple device and single processor environments, the DS1806 can be cascaded or daisy-chained. This feature allows a single processor to control multiple devices. The DS1806 is available in 10, 50 and 100-kohm versions and is specified over the industrial temperature range. Packages for the device include 20-lead DIPs, SOICs, and TSSOPs. OPERATION A block diagram of the device is provided in Figure 1.
PAGE 3
DS1806 Wiper placement for each potentiometer is such that position-63 corresponds to the HX terminal of the device while position-0 corresponds to the ground terminal. For example, to set a potentiometer’s wiper position to 15 (decimal), the binary value shifted into the wiper register should be 00001111. This will place the wiper tap at the 15th step above the low-end terminal, LX. All communication transactions should provide the total 48 bits of information when writing or reading from the part.
PAGE 4
DS1806 3-WIRE SERIAL PORT TIMING Figure 4 CASCADE OPERATION A feature of the DS1806 is the ability to control multiple devices from a single processor. Multiple DS1806s can be linked or daisy chained as shown in Figure 5. As a data bit is entered into the I/O shift register of the DS1806, a bit will appear at the COUT terminal before a maximum delay of 50 nanoseconds. The LSB of potentiometer-1 will always be the first out of the part at the beginning of a transaction.
PAGE 5
DS1806 TYPICAL APPLICATION CONFIGURATIONS Figure 6 shows the typical application configuration of the DS1806 as a fixed gain attenuator. In this configuration, the DS1806 adjusts the attenuation level of the incoming signal. Variations in wiper resistance are minimized by connecting the wiper terminal of the part to a high impedance load. Depending on voltage across the wiper, its resistance may vary from 400 ohms to 1000 ohms.
PAGE 6
DS1806 ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature -0.5V to +7.0V -40°C to +85°C; industrial -55°C to +125°C 260°C for 10 seconds * This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability.
PAGE 7
DS1806 ANALOG RESISTOR CHARACTERISTICS PARAMETER SYMBOL MIN (-40°C to +85°C;VCC=2.7 to 5.5V) TYP MAX UNITS NOTES End-to-End Resistor Tolerance -20 +20 % 10 Absolute Linearity -0.5 +0.5 LSB 7 Relative Linearity -0.25 +0.
PAGE 8
DS1806 4. -3 dB cutoff frequency characteristics for the DS1806 depend on potentiometer total resistance: DS1806-010; 1 MHz; DS1806-050; 200 kHz, DS1806-100; 100 kHz. 5. See Figure 4. 6. For VCC = 5V ± 10% maximum VIL = +0.8V. For VCC = 3.0 ± 10% VIL = +0.6V. 7. Absolute linearity is to used measure expected wiper voltage versus measured wiper voltage as determined by wiper position. The DS1806 is specified to provide an absolute linearity of + 0.5 LSB. 8.