Datasheet

ManualsBrandsANALOG DEVICES ManualsData collecting ICsData acquisition IC - Digital potentiometer linear Non-permanent MSOP 10

Dual, 256-Position, I

C-Compatible

Digital Potentiometers

Data Sheet

AD5243/AD5248

Rev. B

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FEATURES

2-channel, 256-position potentiometers

End-to-end resistance: 2.5 kΩ, 10 kΩ, 50 kΩ, and 100 kΩ

Compact 10-lead MSOP (3 mm × 4.9 mm) package

Fast settling time: t

= 5 µs typical on power-up

Full read/write of wiper register

Power-on preset to midscale

Extra package address decode pins: AD0 and AD1 (AD5248 only)

Computer software replaces microcontroller in factory

programming applications

Single supply: 2.7 V to 5.5 V

Low temperature coefficient: 35 ppm/°C

Low power: I

= 6 µA maximum

Wide operating temperature: −40°C to +125°C

Evaluation board available

APPLICATIONS

Systems calibrations

Electronics level settings

Mechanical trimmers replacement in new designs

Permanent factory PCB setting

Transducer adjustment of pressure, temperature, position,

chemical, and optical sensors

RF amplifier biasing

Automotive electronics adjustment

Gain control and offset adjustment

FUNCTIONAL BLOCK DIAGRAMS

GND

SDA

SCL

WIPER

PC INTERFACE

AD5243

04109-0-001

B1 A2 W2

WIPER

Figure 1. AD5243

GND

SDA

SCL

AD0

AD1

RDAC

ADDRESS

DECODE

SERIAL INPUT

AD5248

B1 W2

RDAC

04109-0-002

Figure 2. AD5248

GENERAL DESCRIPTION

The AD5243 and AD5248 provide a compact 3 mm × 4.9 mm

packaged solution for dual, 256-position adjustment applications.

The AD5243 performs the same electronic adjustment function as

a 3-terminal mechanical potentiometer, and the AD5248 performs

the same adjustment function as a 2-terminal variable resistor.

Available in four end-to-end resistance values (2.5 kΩ, 10 kΩ,

50 kΩ, and 100 kΩ), these low temperature coefficient devices

are ideal for high accuracy and stability-variable resistance

adjustments. The wiper settings are controllable through the

C-compatible digital interface. The AD5248 has extra package

address decode pins, AD0 and AD1, allowing multiple parts to

share the same I

C, 2-wire bus on a PCB. The resistance between

the wiper and either endpoint of the fixed resistor varies linearly

with respect to the digital code transferred into the RDAC latch.

Operating from a 2.7 V to 5.5 V power supply and consuming

less than 6 µA allows the AD5243/AD5248 to be used in portable

battery-operated applications.

For applications that program the AD5243/AD5258 at the factory,

Analog Devices, Inc., offers device programming software running

on Windows® NT/2000/XP operating systems. This software

effectively replaces the need for external I

C controllers, which

in turn enhances the time to market of systems. An AD5243/

AD5248 evaluation kit and software are available. The kit includes

a cable and instruction manual.

The terms digital potentiometer, VR, and RDAC are used interchangeably.

Summary of content (20 pages)

PAGE 1
FEATURES 2-channel, 256-position potentiometers End-to-end resistance: 2.5 kΩ, 10 kΩ, 50 kΩ, and 100 kΩ Compact 10-lead MSOP (3 mm × 4.9 mm) package Fast settling time: tS = 5 µs typical on power-up Full read/write of wiper register Power-on preset to midscale Extra package address decode pins: AD0 and AD1 (AD5248 only) Computer software replaces microcontroller in factory programming applications Single supply: 2.7 V to 5.
PAGE 2
AD5243/AD5248 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Test Circuits ..................................................................................... 12 Applications ....................................................................................... 1 Theory of Operation ...................................................................... 13 Functional Block Diagrams ...............................
PAGE 3
Data Sheet AD5243/AD5248 SPECIFICATIONS ELECTRICAL CHARACTERISTICS: 2.5 kΩ VERSION VDD = 5 V ± 10%, or 3 V ± 10%; VA = VDD; VB = 0 V; −40°C < TA < +125°C; unless otherwise noted. Table 1.
PAGE 4
AD5243/AD5248 Data Sheet ELECTRICAL CHARACTERISTICS: 10 kΩ, 50 kΩ, AND 100 kΩ VERSIONS VDD = 5 V ± 10%, or 3 V ± 10%; VA = VDD; VB = 0 V; −40°C < TA < 125°C; unless otherwise noted. Table 2.
PAGE 5
Data Sheet AD5243/AD5248 TIMING CHARACTERISTICS: ALL VERSIONS VDD = 5 V ± 10%, or 3 V ± 10%; VA = VDD; VB = 0 V; −40°C < TA < +125°C; unless otherwise noted. Table 3.
PAGE 6
AD5243/AD5248 Data Sheet ABSOLUTE MAXIMUM RATINGS TA = 25°C, unless otherwise noted. Table 4. Parameter VDD to GND VA, VB, VW to GND Terminal Current, Ax to Bx, Ax to Wx, Bx to Wx1 Pulsed Continuous Digital Inputs and Output Voltage to GND Operating Temperature Range Maximum Junction Temperature (TJMAX) Storage Temperature Lead Temperature (Soldering, 10 sec) Thermal Resistance, θJA for 10-Lead MSOP2 Rating −0.
PAGE 7
Data Sheet AD5243/AD5248 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS 10 W1 B1 1 A1 2 9 B2 AD0 2 W2 3 AD5248 GND 4 TOP VIEW AD5243 8 A2 GND 4 TOP VIEW 7 SDA VDD 5 6 SCL VDD 5 Figure 4. AD5243 Pin Configuration 10 W1 9 B2 8 AD1 7 SDA 6 SCL 04109-0-028 W2 3 04109-0-027 B1 1 Figure 5. AD5248 Pin Configuration Table 5. AD5243 Pin Function Descriptions Table 6. AD5248 Pin Function Descriptions Pin No. 1 2 3 4 5 6 Mnemonic B1 A1 W2 GND VDD SCL Pin No.
PAGE 8
AD5243/AD5248 Data Sheet TYPICAL PERFORMANCE CHARACTERISTICS 2.0 0.5 TA = 25°C RAB = 10kΩ 1.0 VDD = 2.7V 0.5 0 VDD = 5.5V –0.5 RAB = 10kΩ 0.4 POTENTIOMETER MODE DNL (LSB) –1.0 –1.5 0.3 0.2 0.1 VDD = 2.7V; TA = –40°C, +25°C, +85°C, +125°C 0 –0.1 –0.2 –0.3 32 64 96 128 160 192 224 256 CODE (DECIMAL) –0.5 04109-0-030 0 0 32 128 160 192 224 256 Figure 9. DNL vs. Code vs. Temperature 1.0 0.5 TA = 25°C RAB = 10kΩ 0.3 0.2 VDD = 2.7V 0.1 0 –0.1 –0.2 VDD = 5.5V –0.
PAGE 9
Data Sheet AD5243/AD5248 2.0 4.50 RAB = 10kΩ RAB = 10kΩ 1.0 0.5 0 VDD = 5.5V TA = –40°C, +25°C, +85°C, +125°C –0.5 –1.0 –1.5 0 32 64 96 128 160 192 224 256 CODE (DECIMAL) 3.00 2.25 VDD = 2.7V, VA = 2.7V 1.50 VDD = 5.5V, VA = 5.0V 0.75 0 –40 04109-0-036 –2.0 3.75 –10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) Figure 12. R-INL vs. Code vs. Temperature Figure 15. Zero-Scale Error vs. Temperature 10 0.5 RAB = 10kΩ 0.4 0.3 0.
PAGE 10
AD5243/AD5248 Data Sheet 0 RAB = 10kΩ 0x80 –6 40 0x40 –12 30 GAIN (dB) 20 0x20 –18 VDD = 2.7V TA = –40°C TO +85°C, –40°C TO +125°C 10 0 0x10 –24 0x08 –30 0x04 –36 0x02 –42 –10 0x01 VDD = 5.5V TA = –40°C TO +85°C, –40°C TO +125°C –48 –20 0 32 64 96 128 160 192 224 256 CODE (DECIMAL) –60 1k 10k Figure 18. Potentiometer Mode Tempco ΔVWB/ΔT vs.
PAGE 11
Data Sheet AD5243/AD5248 10 1 VDD = 5.5V VW2 0.1 VDD = 2.7V 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 DIGITAL INPUT VOLTAGE (V) 5.0 04109-0-052 0.01 04109-0-051 VW1 Figure 24. Supply Current vs. Digital Input Voltage Figure 27. Analog Crosstalk VW VW 04109-0-048 04109-0-053 SCL Figure 28. Midscale Glitch, Code 0x80 to Code 0x7F VW2 VW VW1 SCL 04109-0-050 Figure 25. Digital Feedthrough 04109-0-049 IDD, SUPPLY CURRENT (mA) TA = 25°C Figure 29.
PAGE 12
AD5243/AD5248 Data Sheet TEST CIRCUITS Figure 30 through Figure 36 illustrate the test circuits that define the test conditions used in the product specification tables (see Table 1 and Table 2). DUT +15V W VIN AD8610 B B VMS OFFSET GND –15V 2.5V Figure 30. Test Circuit for Potentiometer Divider Nonlinearity Error (INL, DNL) Figure 34. Test Circuit for Gain vs.
PAGE 13
Data Sheet AD5243/AD5248 THEORY OF OPERATION The general equation determining the digitally programmed output resistance between W and B is The AD5243/AD5248 are 256-position, digitally controlled variable resistor (VR) devices. An internal power-on preset places the wiper at midscale during power-on, which simplifies the fault condition recovery at power-up.
PAGE 14
AD5243/AD5248 Data Sheet PROGRAMMING THE POTENTIOMETER DIVIDER TERMINAL VOLTAGE OPERATING RANGE Voltage Output Operation The AD5243/AD5248 VDD and GND power supply defines the boundary conditions for proper 3-terminal digital potentiometer operation. Supply signals present on the A, B, and W terminals that exceed VDD or GND are clamped by the internal forwardbiased diodes (see Figure 42).
PAGE 15
Data Sheet AD5243/AD5248 CONSTANT BIAS TO RETAIN RESISTANCE SETTING For users who desire nonvolatility but cannot justify the additional cost of an EEMEM, the AD5243/AD5248 can be considered low cost alternatives by maintaining a constant bias to retain the wiper setting. The AD5243/AD5248 are designed specifically for low power applications, allowing low power consumption even in battery-operated systems. The graph in Figure 44 demonstrates the power consumption from a 3.
PAGE 16
AD5243/AD5248 Data Sheet I2C INTERFACE I2C COMPATIBLE, 2-WIRE SERIAL BUS SDA line must occur during the low period of SCL and remain stable during the high period of SCL (see Figure 45 and Figure 46). The 2-wire, I C-compatible serial bus protocol operates as follows: 2 1. The master initiates data transfer by establishing a start condition, which is when a high-to-low transition on the SDA line occurs while SCL is high (see Figure 45).
PAGE 17
Data Sheet AD5243/AD5248 Write Mode Table 9. AD5243 Write Mode S 0 1 0 1 1 1 1 W A A0 SD Slave address byte X X X X X X A D7 D6 D5 Instruction byte D4 D3 D2 D1 D0 A P D0 A P Data byte Table 10. AD5248 Write Mode S 0 1 0 1 1 AD1 AD0 W A A0 SD Slave address byte X X X X X X A D7 D6 D5 Instruction byte D4 D3 D2 D1 Data byte Read Mode Table 11.
PAGE 18
AD5243/AD5248 Data Sheet I2C CONTROLLER PROGRAMMING Write Bit Patterns 1 9 9 1 1 9 SDA 0 1 0 1 1 1 1 R/W A0 SD X X X X X X ACK BY AD5243 START BY MASTER D7 D6 D5 D4 D2 D3 D1 FRAME 2 INSTRUCTION BYTE FRAME 1 SLAVE ADDRESS BYTE D0 ACK BY AD5243 ACK BY AD5243 04109-0-022 SCL STOP BY MASTER FRAME 3 DATA BYTE Figure 45.
PAGE 19
Data Sheet AD5243/AD5248 OUTLINE DIMENSIONS 3.10 3.00 2.90 10 3.10 3.00 2.90 1 5.15 4.90 4.65 6 5 PIN 1 IDENTIFIER 0.50 BSC 0.95 0.85 0.75 15° MAX 1.10 MAX 0.30 0.15 0.23 0.13 6° 0° 0.70 0.55 0.40 COMPLIANT TO JEDEC STANDARDS MO-187-BA 091709-A 0.15 0.05 COPLANARITY 0.10 Figure 50. 10-Lead Mini Small Outline Package [MSOP] (RM-10) Dimensions shown in millimeters ORDERING GUIDE Model 1, 2 AD5243BRM2.
PAGE 20
AD5243/AD5248 Data Sheet NOTES Purchase of licensed I2C components of Analog Devices or one of its sublicensed Associated Companies conveys a license for the purchaser under the Philips I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Standard Specification as defined by Philips. ©2004–2012 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04109-0-4/12(B) Rev.