Rainbow Electronics MAX5499 User Manual

General Description

The MAX5494–MAX5499 10-bit (1024-tap), dual, non­volatile, linear-taper, programmable voltage-dividers
and variable resistors perform the function of a
mechanical potentiometer, but replace the mechanics
with a 3-wire SPI™-compatible serial interface. The
MAX5494/MAX5495 are dual, 3-terminal, programma­ble voltage-dividers; the MAX5496/MAX5497 are dual,
2-terminal variable resistors; and the MAX5498/
MAX5499 include one 2-terminal variable resistor and
one 3-terminal programmable voltage-divider.

The MAX5494–MAX5499 feature an internal, nonvolatile,
electrically erasable programmable read-only memory
(EEPROM) that stores the wiper position for initialization
during power-up. The 3-wire SPI-compatible serial inter­face allows communication at data rates up to 7MHz.

The MAX5494–MAX5499 are ideal for applications requir­ing digitally controlled potentiometers. End-to-end resis­tance values of 10kΩ and 50kΩ are available with a
35ppm/°C end-to-end temperature coefficient. The ratio­metric temperature coefficient is 5ppm/°C for each chan­nel, making these devices ideal for applications requiring
low-temperature-coefficient programmable voltage­dividers such as low-drift, programmable-gain amplifiers.

The MAX5494–MAX5499 operate with either a single
power supply (+2.7V to +5.25V) or dual power supplies
(±2.5V). The devices consume 400µA (max) of supply
current when writing data to the nonvolatile memory
and 1.5µA (max) of standby supply current. The
devices are available in space-saving (5mm x 5mm x

0.8mm), 16-pin TQFN package and are specified over
the extended (-40°C to +85°C) temperature range.

Applications

Gain and Offset Adjustment
LCD Contrast Adjustment
Pressure Sensors
Low-Drift Programmable-Gain Amplifiers
Mechanical Potentiometer Replacement
Volume Control

Features

♦ Wiper Position Stored in Nonvolatile Memory and

Recalled Upon Power-Up

♦ 16-Pin, 5mm x 5mm x 0.8mm TQFN Package

♦ 35ppm/°C End-to-End Resistance Temperature

Coefficient

♦ 5ppm/°C Ratiometric Temperature Coefficient
♦ 10kΩ and 50kΩ End-to-End Resistor Values

♦ 3-Wire SPI-Compatible Serial Interface

♦ Reliability (TA= +85°C)

50,000 Wiper Store Cycles
50 Years Wiper Data Retention

♦ 1.5µA (max) Standby Current

♦ Single +2.7V to +5.25V Supply Operation

♦ Dual ±2.5V Supply Operation

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

________________________________________________________________ Maxim Integrated Products 1

16

1234

12 11 10 9

15

14

13

5

6

7

8

SCLK

N.C.

N.C.

DIN

GNDINTERFACE

W1

L1

H1

W2

L2

H2

V

DD

N.C.

N.C.

V

SS

TOP VIEW

MAX5494
MAX5495

CS

5mm × 5mm × 0.8mm TQFN

16

1234

12 11 10 9

15

14

13

5

6

7

8

SCLK

N.C.

N.C.

DIN

GNDINTERFACE

W1

L1

D.N.C.

W2

L2

D.N.C.

V

DD

N.C.

N.C.

V

SS

MAX5496
MAX5497

CS

5mm × 5mm × 0.8mm TQFN

Pin Configurations

Ordering Information

19-3562; Rev 1; 6/05

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

*EP = Exposed pad.

Ordering Information continued at end of data sheet.
Selector Guide appears at end of data sheet.

Pin Configurations continued at end of data sheet.

SPI is a trademark of Motorola, Inc.

MAX5494ETE -40°C to +85°C 16 TQFN-EP* T1655-2

MAX5495ETE -40°C to +85°C 16 TQFN-EP* T1655-2

PART TEMP RANGE

PIN­PACKAGE

PKG CODE

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VDD= +2.7V to +5.25V, VSS= GND = 0, VH_= VDD, VL_= 0, TA= -40°C to +85°C, unless otherwise noted. Typical values are at
V

DD

= +5.0V, TA= +25°C.) (Note 1)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

VDDto GND...........................................................-0.3V to +6.0V

V

SS

to GND............................................................-6.0V to +0.3V

V

DD

to VSS.............................................................-0.3V to +6.0V

H1, H2, L1, L2, W1, W2 to V

SS

.........(VSS- 0.3V) to (VDD+ 0.3V)

CS, SCLK, DIN to GND ..............................-0.3V to (VDD+ 0.3V)

Maximum Continuous Current into H_, L_, and W_

MAX5494/MAX5496/MAX5498 ....................................±5.0mA

MAX5495/MAX5497/MAX5499 ....................................±1.0mA

Maximum Current Into Other Pins .................................±50.0mA

Continuous Power Dissipation (T

A

= +70°C)

16-Pin TQFN (derate 20.8mW/°C above +70°C) ....1666.7mW

Operating Temperature Range ...........................-40°C to +85°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-60°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

PARAMETER

CONDITIONS

UNITS

DC PERFORMANCE (MAX5494/MAX5495/MAX5498/MAX5499 Programmable Voltage-Divider)

Resolution N 10 Bits

VDD = 2.7V ±2

Integral Nonlinearity (Note 2) INL

V

DD

= 5V ±2

LSB

VDD = 2.7V ±1

Differential Nonlinearity (Note 2) DNL

V

DD

= 5V ±1

LSB

End-to-End Resistance
Temperature Coefficient

TC

R

35

ppm/°C

Ratiometric Temperature
Coefficient

5

ppm/°C

MAX5494/MAX5498 -4 -2.5 0

Full-Scale Error FSE

MAX5495/MAX5499 -4

0

LSB

MAX5494/MAX5498 0 3.3 5

Zero-Scale Error ZSE

MAX5495/MAX5499 0

5

LSB

Wiper Capacitance C

W

60 pF

MAX5494/MAX5498 7.5 10

End-to-End Resistance R

HL

MAX5495/MAX5499

50

kΩ

MAX5494

Channel-to-Channel Division
Ratio Matching

MAX5495

%

MAX5494/MAX5498, W_ at 15 code, H_ and
L_ shorted to V

SS

, measure resistance from

W_ to H_ (Figures 4 and 5)

6.3

Resistance from W_ to L_ and H_

MAX5495/MAX5499, W_ at 15 code, H_ and
L_ shorted to V

SS

, measure resistance from

W_ to H_ (Figures 4 and 5)

25

kΩ

SYMBOL

MIN TYP MAX

VDD = 3V, midcode: 512

-0.75

1.45

37.5

0.05

0.15

12.5

62.5

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +2.7V to +5.25V, VSS= GND = 0, VH_= VDD, VL_= 0, TA= -40°C to +85°C, unless otherwise noted. Typical values are at
V

DD

= +5.0V, TA= +25°C.) (Note 1)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

DC PERFORMANCE (MAX5496–MAX5499 Variable Resistor)

Resolution N 10 Bits

VDD = 2.7V -1.6

VDD = 3V -4 -1.4 +4Integral Nonlinearity (Note 3) INL_R

V

DD

= 5V -4 -1.3 +4

LSB

VDD = 2.7V

VDD = 3V -1

+1Differential Nonlinearity (Note 3) DNL_R

V

DD

= 5V -1

+1

LSB

Variable-Resistor Temperature
Coefficient

TC

VR

VDD = 3V to 5.25V; code = 128 to 1024 35

ppm/°C

Wiper Resistance R

W

VDD ≥ 3V (Note 4) 50 Ω

Wiper Capacitance C

WR

60 pF

MAX5496/MAX5498 7.5 10

Full-Scale Wiper-to-End
Resistance

R

W-L

MAX5497/MAX5499

50

kΩ

70

Zero-Scale Resistor Error R

Z

Code = 0

110

Ω

MAX5496/MAX5498,
Code >128

0.1

Two-Channel Resistance
Matching

V

DD

= 3V to 5.25V

MAX5497/MAX5499,
Code >200

%

DIGITAL INPUTS (CS, SCLK, DIN) (Note 5)

2.4

Single-supply
operation

V

DD

= 2.7V to 3.6V

0.7 x

Input High Voltage V

IH

Dual-supply
operation

With respect to
GND, V

DD

= 2.5V,

V

SS

= -2.5V

2.0

V

Single-supply
operation

0.8

Input Low Voltage V

IL

Dual-supply
operation

With respect to
GND, V

DD

= 2.5V,

V

SS

= -2.5V

0.6

V

Input Leakage Current I

IN

±1 µA

Input Capacitance C

IN

5pF

DYNAMIC CHARACTERISTICS

250

Wiper -3dB Bandwidth BW

Wiper at code 495
(01111 01111), 10pF
load at wiper

50

kHz

+0.45

MAX5494/MAX5498

MAX5495/MAX5499

VDD = 3.6V to 5.25V

+0.4

+0.35

37.5

V

DD

0.15

12.5

62.5

VDD = 2.7V to 5.25V

MAX5494/MAX5498

MAX5495/MAX5499

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +2.7V to +5.25V, VSS= GND = 0, VH_= VDD, VL_= 0, TA= -40°C to +85°C, unless otherwise noted. Typical values are at
V

DD

= +5.0V, TA= +25°C.) (Note 1)

PARAMETER

CONDITIONS

UNITS

MAX5494/MAX5498; VDD = 3V; wiper at
code 495; 10kHz, 1V

RMS

signal is applied

at H_; 10pF load at wiper

Total Harmonic Distortion THD

MAX5495/MAX5499; V

DD

= 3V; wiper at

code 495; 10kHz, 1V

RMS

signal is applied

at H_;

10pF load at wiper

%

Analog Crosstalk

CH2 = 11111 11111, CH1 = 01111 01111,
C

W_

= 10pF, VH1 = VDD = +2.5V,

V

L1

= VSS = -2.5V, measure VW1 with

V

W2

= 5V

P-P

at f = 1kHz

-93 dB

NONVOLATILE MEMORY RELIABILITY

Data Retention TA = +85°C 50

Years

TA = +25°C

Endurance

T

A

= +85°C

Stores

POWER SUPPLIES

Single-Supply Voltage V

DD

VSS = GND = 0

V

V

DD

GND = 0

Dual-Supply Voltage

V

SS

(VDD - VSS) ≤ 5.25V

V

Average Programming Current I

PG

During nonvolatile write only;
digital inputs = V

DD

or GND

220

µA

Peak Programming Current

During nonvolatile write only;
digital inputs = V

DD

or GND

4mA

Standby Current I

DD

Digital inputs = VDD or GND, TA = +25°C 0.6 1.5 µA

SYMBOL

MIN TYP MAX

0.026

0.03

200,000

50,000

2.70 5.25

2.50 5.25

-2.5 -0.2

400

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

_______________________________________________________________________________________ 5

TIMING CHARACTERISTICS

(VDD= +2.7V to +5.25V, VSS= GND = 0, VH_= VDD, VL_= 0, TA= -40°C to +85°C, unless otherwise noted. Typical values are at
V

DD

= +5.0V, TA= +25°C.) (Note 1)

PARAMETER

CONDITIONS

UNITS

ANALOG SECTION

MAX5494/MAX5498 5

Wiper Settling Time (Note 6) t

S

MAX5495/MAX5499 22

µs

SPI-COMPATIBLE SERIAL INTERFACE (Figure 6)

SCLK Frequency f

SCLK

7 MHz

SCLK Clock Period t

CP

ns

SCLK Pulse-Width High t

CH

60 ns

SCLK Pulse-Width Low t

CL

60 ns

CS Fall to SCLK Rise Setup t

CSS

60 ns

SCLK Rise to CS Rise Hold t

CSH

0ns

DIN to SCLK Setup t

DS

40 ns

DIN Hold After SCLK t

DH

0ns

SCLK Rise to CS Fall Delay t

CS0

15 ns

CS Rise to SCLK Rise Hold t

CS1

60 ns

CS Pulse-Width High t

CSW

ns

Write NV Register Busy Time t

BUSY

12 ms

Note 1: 100% production tested at TA= +25°C and TA= +85°C. Guaranteed by design to TA= -40°C.
Note 2: The DNL and INL are measured for the voltage-divider with H_ = V

DD

and L_ = VSS. The wiper terminal (W_) is unloaded

and measured with a high-input-impedance voltmeter.

Note 3: The DNL and INL are measured with L_ = V

SS

= 0. For VDD= 5V, the wiper terminal is driven with a current source of IW=

80µA for the 50kΩ device and I

W

= 400µA for the 10kΩ device. For VDD= 3V, the wiper terminal is driven with a current

source of IW= 40µA for the 50kΩ device and IW= 200µA for the 10kΩ device.

Note 4: The wiper resistance is measured using the source currents given in Note 3.
Note 5: The device draws higher supply current when the digital inputs are driven with voltages between (V

DD

- 0.5V) and (GND +

0.5V). See the Supply Current vs. Digital Input Voltage graph in the Typical Operating Characteristics.

Note 6: Wiper settling test condition uses the voltage-divider with a 10pF load on W_. Transition code from 0 to 495 and measure

the time from CS going high to the wiper voltage settling to within 0.5% of its final value.

SYMBOL

MIN TYP MAX

140

150

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

6 _______________________________________________________________________________________

Typical Operating Characteristics

(VDD= +5.0V, VSS= 0, TA= +25°C, unless otherwise noted.)

DIFFERENTIAL NONLINEARITY

vs. CODE (VARIABLE RESISTOR)

MAX5494 toc01

CODE

DNL (LSB)

896768512 640256 384128

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1.0

-1.0
01024

VDD = 3V

INTEGRAL NONLINEARITY

vs. CODE (VARIABLE RESISTOR)

MAX5494 toc02

CODE

INL (LSB)

896768512 640256 384128

-1.0

-0.5

0

0.5

1.0

1.5

-1.5
0 1024

VDD = 3V

MAXIMUM DIFFERENTIAL NONLINEARITY

vs. SUPPLY VOLTAGE (VARIABLE RESISTOR)

MAX5494 toc03

VDD (V)

DNL (LSB)

4.54.03.53.0

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1.0

-1.0

2.5 5.0

MAXIMUM INTEGRAL NONLINEARITY

vs. SUPPLY VOLTAGE (VARIABLE RESISTOR)

MAX5494 toc04

VDD (V)

INL (LSB)

4.54.03.53.0

-1.5

-1.0

-0.5

0

0.5

1.0

-2.0

2.5 5.0

DIFFERENTIAL NONLINEARITY

vs. CODE (VOLTAGE-DIVIDER)

MAX5494 toc05

CODE

DNL (LSB)

896768512 640256 384128

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1.0

-1.0
0 1024

VDD = 3V

INTEGRAL NONLINEARITY

vs. CODE (VOLTAGE-DIVIDER)

MAX5494 toc06

CODE

INL (LSB)

896768512 640256 384128

-1.0

-0.5

0

0.5

1.0

1.5

-1.5
01024

VDD = 3V

WIPER RESISTANCE vs. CODE

(VARIABLE RESISTOR)

MAX5494 toc07

CODE

R

W

(Ω)

896768512 640256 384128

10

20

40

30

50

60

70

80

0

01024

0

10

20

30

40

50

60

0256128 384 512 640 768 896 1024

END-TO-END RESISTANCE

vs. CODE (MAX5497/MAX5499)

MAX5494 toc08

CODE

R

WL

(kΩ)

END-TO-END RESISTANCE vs. CODE

(MAX5496/MAX5498)

MAX5494 toc09

CODE

R

WL

(kΩ)

896768512 640256 384128

2

4

6

8

10

12

0

01024

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

_______________________________________________________________________________________ 7

Typical Operating Characteristics (continued)

(VDD= +5.0V, VSS= 0, TA= +25°C, unless otherwise noted.)

WIPER RESISTANCE vs. WIPER VOLTAGE

(VARIABLE RESISTOR)

MAX5494 toc10

WIPER VOLTAGE (V)

R

W

(Ω)

4321

17

19

20

21

22

16

05

CODE IS 00 0000 0000

VDD = 5V

18

END-TO-END RESISTANCE (RHL)

% CHANGE vs. TEMPERATURE

(VOLTAGE-DIVIDER)

MAX5494 toc11

TEMPERATURE (°C)

END-TO-END RESISTANCE CHANGE (%)

603510-15

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1.0

-1.0

-40 85

WIPER-TO-END RESISTANCE (RWL)

% CHANGE vs. TEMPERATURE

(VARIABLE RESISTOR)

MAX5494 toc12

TEMPERATURE (°C)

WIPER-TO-END RESISTANCE CHANGE (%)

603510-15

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1.0

-1.0

-40 85

CODE IS 11 1111 1111

STANDBY SUPPLY CURRENT

vs. TEMPERATURE

MAX5494 toc13

TEMPERATURE (°C)

I

DD

(µA)

603510-15

0.3

0.6

0.9

1.2

1.5

0

-40 85

VDD = 5.25V

DIGITAL SUPPLY CURRENT

vs. DIGITAL INPUT VOLTAGE

MAX5494 toc14

DIGITAL INPUT VOLTAGE (V)

I

DD

(µA)

4321

1

10

100

1000

10,000

0.1
05

VDD = 5V

RATIOMETRIC TEMPERATURE

COEFFICIENT vs. CODE

MAX5494 toc15

CODE

RATIOMETRIC TEMPCO (ppm/°C)

896768512 640256 384128

20

40

60

80

100

120

140

160

180

200

0

01024

VOLTAGE-DIVIDER
V

DD

= 3V

T

A

= -40°C TO +85°C

10kΩ

50kΩ

VARIABLE RESISTOR TEMPERATURE

COEFFICIENT vs. CODE

MAX5494 toc16

CODE

TC

VR

(ppm/°C)

896768512 640256 384128

100

200

300

400

500

600

700

0

01024

VDD = 3V
T

A

= -40°C TO +85°C

10kΩ

50kΩ

TAP-TO-TAP SWITCHING TRANSIENT

(MAX5494/MAX5498)

MAX5494 toc17

V

W_

20mV/div

1µs/div

CS
2V/div

H_ = V

DD

L_ = GND
FROM CODE 01111 11111
TO CODE 10000 00000
C

W_

= 10pF

TAP-TO-TAP SWITCHING TRANSIENT

(MAX5495/MAX5499)

MAX5494 toc18

V

W_

20mV/div

4µs/div

H_ = V

DD

L_ = GND
FROM CODE 01111 11111
TO CODE 10000 00000
C

W_

= 10pF

CS
2V/div

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

8 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VDD= +5.0V, VSS= 0, TA= +25°C, unless otherwise noted.)

CROSSTALK

MAX5494 toc19

V

W1

20mV/div

400ns/div

V

W2

2V/div

VH2 = V

DD

VL2 = VL1 = VH1 = GND
C

W_

= 10pF

CROSSTALK vs. FREQUENCY

MAX5494 toc20

FREQUENCY (kHz)

CROSSTALK (dB)

1010.1

-40

-20

0

0.01 100

CW_ = 10pF
CODE = 01111 01111

-60

-80

-100

-120
1000

MAX5494/MAX5498

MAX5495/MAX5499

THD+N vs. FREQUENCY

(MAX5494/MAX5498)

MAX5494 toc21

FREQUENCY (kHz)

THD+N (%)

1010.1

0.001

0.01

0.1

1

10

0.0001

0.01 100

CW_ = 10pF
CODE = 01111 01111

THD+N vs. FREQUENCY

(MAX5495/MAX5499)

MAX5494 toc22

FREQUENCY (kHz)

THD+N (%)

1010.1

0.001

0.01

0.1

1

10

0.0001

0.01 100

CW_ = 10pF
CODE = 01111 01111

WIPER RESPONSE vs. FREQUENCY

(MAX5494/MAX5498)

MAX5494 toc23

FREQUENCY (kHz)

GAIN (dB)

100101

-20

-15

-10

-5

0

-25

0.1 1000

CODE = 01111 01111

CW_ = 10pF

CW_ = 30pF

WIPER RESPONSE vs. FREQUENCY

(MAX5495/MAX5499)

MAX5494 toc24

FREQUENCY (kHz)

GAIN (dB)

100101

-20

-15

-10

-5

0

-25

0.1 1000

CODE = 01111 01111

CW_ = 10pF

CW_ = 30pF

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

_______________________________________________________________________________________ 9

Pin Descriptions

PIN

MAX5494/

MAX5495

NAME FUNCTION

111CS

Active-Low Chip-Select Input. Drive CS low to enable the serial interface. Drive
CS high to disable the serial interface and put the device in standby mode.

222W2Wiper Terminal 2

333L2Low Terminal 2

4——H2High Terminal 2

555V

DD

Positive Power-Supply Input. 2.7V ≤ V

DD

≤ 5.25V. Bypass with a 0.1µF

capacitor from V

DD

to GND as close to the device as possible

6, 7,14,15

N.C. No Connection. Not internally connected.

888V

SS

Negative Power-Supply Input.
Single-supply operation: V

SS

= GND = 0.

Dual-supply operation: -2.5V ≤ V

SS

≤ -0.2V (VSS can vary as long as

(V

DD

- VSS) ≤ 5.25V).

Bypass with a 0.1µF capacitor from V

SS

to GND as close to the device

as possible.

9—9H1High Terminal 1

10 10 10 L1 Low Terminal 1

11 11 11 W1 Wiper Terminal 1

12 12 12 GND Ground

13 13 13 DIN

Serial-Data Input. The data at DIN synchronously loads into the serial shift
register on each SCLK rising edge.

16 16 16 SCLK Serial-Clock Input . SCLK clocks in the data when CS is low.

— 4, 9 4 D.N.C Do Not Connect. Leave unconnected for proper operation.

EP EP EP

Exposed

Pad

Exposed Pad. Externally connect EP to V

SS

to provide a low thermal resistance

path from the IC junction to the PC board or leave unconnected.

MAX5496/

MAX5497

6, 7,14,15 6, 7,14,15

MAX5498/

MAX5499

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

10 ______________________________________________________________________________________

Functional Diagrams

MAX5494
MAX5495

POR

10-BIT
LATCH

2 x 10

BIT

NVM

SCLK

DIN

CS

DECODER

10

10

1024

TAPS

H1

W1

L1

V

DD

GND

V

SS

SPI

INTERFACE

DECODER

10-BIT
LATCH

H2

W2

NOTE: THE PROGRAMMABLE VOLTAGE-DIVIDER IS NOT INTENDED FOR CURRENT TO FLOW THROUGH THE WIPER.

NOTE: SEE THE MAX5494/MAX5495/MAX5498/MAX5499 PROGRAMMABLE VOLTAGE-DIVIDERS SECTION.

L2

1024

TAPS

Figure 1. MAX5494/MAX5495 Functional Diagram

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

______________________________________________________________________________________ 11

Functional Diagrams (continued)

MAX5496
MAX5497

POR

10-BIT

LATCH

2 x 10

BIT

NVM

SCLK

DIN

CS

DECODER

10

10

W1

L1

V

DD

GND

V

SS

SPI

INTERFACE

DECODER

10-BIT
LATCH

W2

L2

1024

TAPS

1024

TAPS

Figure 2. MAX5496/MAX5497 Functional Diagram

MAX5498
MAX5499

POR

10-BIT
LATCH

2 x 10

BIT

NVM

SCLK

DIN

CS

DECODER

10

10

H1

W1

L1

V

DD

GND

V

SS

SPI

INTERFACE

10-BIT
LATCH

DECODER

W2

L2

NOTE: THE PROGRAMMABLE VOLTAGE-DIVIDER IS NOT INTENDED FOR CURRENT TO FLOW THROUGH THE WIPER.

NOTE: SEE THE MAX5494/MAX5495/MAX5498/MAX5499 PROGRAMMABLE VOLTAGE-DIVIDERS SECTION.

1024

TAPS

1024

TAPS

Figure 3. MAX5498/MAX5499 Functional Diagram

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

12 ______________________________________________________________________________________

CODE (DECIMAL)

R

W_H_

(kΩ)

896768512 640256 384128

2

4

6

8

10

12

14

16

18

0

0 1024

50kΩ SCALES BY A FACTOR OF FIVE

Figure 4. Resistance from W_ to H_ vs. Code (10kΩ Voltage­Divider)

CODE (DECIMAL)

R

W_L_

(kΩ)

896768512 640256 384128

2

4

6

8

10

12

14

16

18

0

0 1024

50kΩ SCALES BY A FACTOR OF FIVE

Figure 5. Resistance from W_ to L_ vs. Code (10kΩ Voltage­Divider)

Detailed Description

The MAX5494–MAX5499 dual, nonvolatile, linear-taper,
programmable voltage-dividers and variable resistors
feature 1024 tap points (10-bit resolution) (see the
Functional Diagrams). These devices consist of multi­ple strings of equal resistor segments with a wiper con­tact that moves among the 1024 effective tap points by
a 3-wire SPI-compatible serial interface. The
MAX5494/MAX5496/MAX5498 provide a total 10kΩ
end-to-end resistance, and the MAX5495/MAX5497/
MAX5499 feature a 50kΩ end-to-end resistance. The
MAX5494/MAX5495/MAX5498/MAX5499 allow access
to the high, low, and wiper terminals for a standard volt­age-divider configuration. Ensure that the terminal volt­ages fall between VSSand VDD.

MAX5494/MAX5495/MAX5498/MAX5499

Programmable Voltage-Dividers

The MAX5494/MAX5495/MAX5498/MAX5499 program­mable voltage-dividers provide a weighted average of
the voltage between the H_ and L_ inputs at the W_
output.

The MAX5494/MAX5495/MAX5498/MAX5499 program­mable voltage-divider network provides up to 1024
division ratios between the H_ and L_ voltage. Ideally,
the VLvoltage occurs at the wiper terminal when all
data bits are zeros and the VHvoltage occurs at the
wiper terminal when all data bits are one (see the wiper
voltage equation). The step-size voltage (1 LSB) is
equal to the voltage applied across terminals H and L
divided by 210. Calculate the wiper voltage VWas fol­lows:

where D is the decimal equivalent of the 10 data bits

written (0 to 1023), VHLis the voltage difference between

the H_ and L_ terminals, and:

The MAX5494/MAX5498 provide a 10kΩ end-to-end
resistance value, while the MAX5495/MAX5499 feature a
50kΩ end-to-end resistance value. Note that the pro-

grammable voltage-divider is not intended to be used
as a variable resistor. Wiper current creates a nonlinear

voltage drop in series with the wiper. To ensure tempera­ture drift remains within specifications, do not pull current
through the voltage-divider wiper. Connect the wiper to a
high-impedance node. Figures 4 and 5 show the behav­ior of the programmable voltage-divider resistance from
W_ to H_ and W_ to L_, respectively. This does not apply
to the variable-resistor devices.

MAX5496–MAX5499 Variable Resistors

The MAX5496–MAX5499 provide a programmable resis­tance from W_ to L_. The MAX5496/MAX5498 provide a
10kΩ end-to-end resistance value, while the
MAX5497/MAX5499 feature a 50kΩ end-to-end resis­tance value. The programmable resolution of this

V FSE

V

V ZSE

V

FSE

HL

ZSE

HL

=











=











1024

1024

D

VV V

VV

HL FSE ZSE

L ZSE

−+

()















++

||||

||

1023

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

______________________________________________________________________________________ 13

resistance is equal to the nominal end-to-end resis­tance divided by 1024 (10-bit resolution). For example,
the programmable resolution is 9.8Ω and 48.8Ω for the
MAX5496/MAX5498 and the MAX5497/MAX5499,
respectively.

The 10-bit data in the 10-bit latch register selects the
wiper position from the 1024 possible positions, result­ing in 1024 values for the resistance from W_ to L_.
Calculate the resistance from W_ to L_ (RWL) from the
formula below:

where D is decimal equivalent of the 10 data bits writ­ten, R

W-L

is the nominal end-to-end resistance, and R

Z

is the zero-scale error. Table 1 shows RWLat selected
codes.

SPI-Compatible Serial Interface

The MAX5494–MAX5499 use a 3-wire, SPI-compatible,
serial data interface (Figure 6). This write-only interface
contains three inputs: chip-select (CS), data input
(DIN), and data clock (SCLK). Drive CS low to enable
the serial interface and clock data synchronously into
the shift register on each SCLK rising edge.

The WRITE commands (C1, C0 = 00 or 01) require 24
clock cycles to transfer the command and data (Figure
7a). The COPY commands (C1, C0 = 10 or 11) use

either eight clock cycles to transfer the command bits
(Figure 7b) or 24 clock cycles with 16 bits disregarded
by the device (Figure 7a).

After the loading of data into the shift register, drive CS
high to latch the data into the appropriate control regis­ter (specified by RA1 and RA0) and disable the serial
interface. Keep CS low during the entire serial data
stream to avoid corruption of the data. Table 2 shows
the register map.

Write Wiper Register

The “write wiper register” command (C1, C0 = 00) con­trols the wiper positions. The 10 data bits (D9–D0) indi­cate the position of the wiper. For example, if DIN =
000000 0000, the wiper moves to the position closest to
L_. If DIN = 11 1111 1111, the wiper moves closest to H_.

RD

D

RR

WL W L Z

()

=×+

−

1023

END-TO-END RESISTANCE VALUE

10kΩ 50kΩ

CODE (DECIMAL)

RWL (Ω)R

WL

(Ω)

070110

180160

512 5,070 25,110

1023 10,070 50,110

Table 1. RWLat Selected Codes

CS

t

CSO

t

CSS

t

CL

t

CH

t

DH

t

DS

t

CP

t

CSH

t

CSW

t

CS1

SCLK

DIN

Figure 6. SPI-Interface Timing Diagram

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

14 ______________________________________________________________________________________

1 2 3 4 5 6 7 8 9

10

D9 D8 D7 D6 D5 D4 D3 D2

a) 24-BIT COMMAND/DATA WORD

1 2 3 4 5 6 7 8

C1 C0

b) 8-BIT COMMAND WORD

D1 D0

SCLK

SCLK

DIN

DIN

CS

11 12

13 14 15 16

17

18 19 20 21 22

23 24

CS

C1 C0

RA0RA1

RA0RA1

Figure 7. SPI-Compatible Serial-Interface Format

Table 2. Register Map*

CLOCK EDGE

24

Bit Name

—

Write Wiper Register 1

—

Write Wiper Register 2

—

Write NV Register 1

—

Write NV Register 2

—

Copy Wiper Register 1
to NV Register 1

—

Copy Wiper Register 2
to NV Register 2

—

Copy Wiper Register 1
to NV Register 1 and
Copy Wiper Register 2
to NV Register 2
Simultaneously

—

Copy NV Register 1 to
Wiper Register 1

—

Copy NV Register 2 to
Wiper Register 2

—

Copy NV Register 1 to
Wiper Register 1 and
Copy NV Register 2 to
Wiper Register 2
Simultaneously

—

*D9 is the MSB and D0 is the LSB of the data bits.

12 3 4 56 7 8 9101112131415161718…

——C1C0——RA1 RA0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 —

00 0 0 00 0 1D9D8 D7 D6 D5 D4 D3 D2 D1 D0 —

00 0 0 00 1 0D9D8 D7 D6 D5 D4 D3 D2 D1 D0 —

00 0 1 00 0 1D9D8 D7 D6 D5 D4 D3 D2 D1 D0 —

00 0 1 00 1 0D9D8 D7 D6 D5 D4 D3 D2 D1 D0 —

00 1 0 00 0 1———————————

00 1 0 00 1 0———————————

00 1 0 00 1 1———————————

00 1 1 00 0 1———————————

00 1 1 00 1 0———————————

00 1 1 00 1 1———————————

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

______________________________________________________________________________________ 15

ACTION

WIPER

REGISTER 1

UPDATED

000 000 01 D9D8 D7 D6 D5 D4 D3 D2 D1 D0

12345678 910111213141516 1718192021222324

SCLK

DIN

XXXXXX

CS

C1 C0 RA1 RA0

Figure 8. Write Wiper Register 1

Figure 9. Write NV Register 1

The “write wiper register” command writes data to the
volatile random access memory (RAM), leaving the NV
registers unchanged. When the device powers up, the
data stored in the NV registers transfers to the wiper
register, moving the wiper to the stored position. Figure
8 shows how to write data to wiper register 1.

Write NV Register

The “write NV register” command (C1, C0 = 01) stores
the position of the wiper to the NV registers for use at
power-up. Alternatively, the “copy wiper register to NV
register” command writes to the NV register. Writing to

the NV register does not affect the position of the
wipers. The operation takes up to 12ms (max) after CS
goes high to complete and no other operation should
be performed until completion. Figure 9 shows how to
write data to the NV register 1.

Copy Wiper Register to NV Register

The “copy wiper register to NV register” command (C1,
C0 = 10) stores the current position of the wiper to the
NV register for use at power-up. Figure 10 shows how
to copy data from wiper register 1 to NV register 1.

CS

12345678 910111213141516 1718192021222324

SCLK

DIN

ACTION

000 100 01 D9D8 D7 D6 D5 D4 D3 D2 D1 D0

C1 C0 RA1 RA0

XXXXXX

t

BUSY

WRITE NV

REGISTER 1

(DEVICE IS BUSY)

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

16 ______________________________________________________________________________________

Copy NV Register to Wiper Register

The “copy NV register to wiper register” (C1, C0 = 11)
restores the wiper position to the current value stored in
the NV register. Figure 11 shows how to copy data from
NV register 1 to wiper register 1.

Standby Mode

The MAX5494–MAX5499 feature a low-power standby
mode. When the device is not being programmed, it
enters into standby mode and supply current drops to

0.6µA (typ).

Nonvolatile Memory

The internal EEPROM consists of a nonvolatile register
that retains the last value stored prior to power-down.
The nonvolatile register is programmed to midscale at

the factory. The nonvolatile memory is guaranteed for
50 years for wiper data retention and up to 200,000
wiper write cycles.

Power-Up

Upon power-up, the MAX5494–MAX5499 load the data
stored in the nonvolatile wiper register into the wiper
register, updating the wiper position with the data
stored in the nonvolatile wiper register.

Applications Information

The MAX5494–MAX5499 are intended for circuits
requiring digitally controlled adjustable resistance,
such as LCD contrast control (where voltage biasing
adjusts the display contrast), or programmable filters
with adjustable gain and/or cutoff frequency.

ACTION

00100001

12345678

SCLK

DIN

CS

C1 C0 RA1 RA0

WRITE NV

REGISTER 1

(DEVICE IS BUSY)

t

BUSY

Figure 10. Copy Wiper Register 1 to NV Register 1

ACTION

00110001

12345678

SCLK

DIN

CS

C1 C0 RA1 RA0

WIPER REGISTER

1 UPDATED

Figure 11. Copy NV Register 1 to Wiper Register 1

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

______________________________________________________________________________________ 17

Positive LCD Bias Control

Figures 12 and 13 show an application where the volt­age-divider or variable resistor is used to make an
adjustable, positive LCD-bias voltage. The op amp pro­vides buffering and gain to the resistor-divider network.

Programmable Filter

Figure 14 shows the configuration for a 1st-order pro­grammable filter. The gain of the filter is adjusted by
R2, and the cutoff frequency is adjusted by R3. Use the
following equations to calculate the gain (G) and the
3dB cutoff frequency (f

C

).

Gain and Offset Voltage Adjustment

Figure 15 shows an application using the MAX5498/
MAX5499 to adjust the gain and nullify the offset voltage.

G

R

R

f

RC

C

=+

=

××

1

1

2

1

23π

V

OUT

30V

5V

W_

H_

L_

1/2 MAX5494/MAX5495
1/2 MAX5498/MAX5499

MAX480

Figure 12. Positive LCD Bias Control Using a Voltage-Divider

V

OUT

30V

5V

W_

L_

1/2 MAX5496–MAX5499

MAX480

Figure 13. Positive LCD Bias Control Using a Variable Resistor

V

OUT

V

IN

R1

R2

R3

C

W_

L_

W_

L_

1/2 MAX5496–MAX5499

1/2 MAX5496–MAX5499

Figure 14. Programmable Filter

V

OUT

W_

L_

1/2 MAX5498/MAX5499

1/2 MAX5498/MAX5499

V

REF

W_

H_

L_

V

IN

Figure 15. Gain- and Offset-Voltage Adjustment Circuit

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

18 ______________________________________________________________________________________

16

1234

12 11 10 9

15

14

13

5

6

7

8

SCLK

N.C.

N.C.

DIN

GNDINTERFACE

W1

L1

H1

W2

L2

D.N.C.

V

DD

N.C.

N.C.

V

SS

TOP VIEW

MAX5498
MAX5499

CS

5mm × 5mm × 0.8mm TQFN

Pin Configurations (continued)

Ordering Information (continued)

PART CONFIGURATION

END-TO-END

RESISTANCE

(kΩ)

MAX5494ETE

Two programmable voltage­dividers

10

MAX5495ETE

Two programmable voltage­dividers

50

MAX5496ETE

Two variable resistors 10

MAX5497ETE

Two variable resistors 50

MAX5498ETE

One p r og r amm ab le vol tage-

10

MAX5499ETE

One p r og r amm ab le vol tage-

50

Selector Guide

Chip Information

TRANSISTOR COUNT: 32,262

PROCESS: BiCMOS

*EP = Exposed pad.

d i vi d er and one vari ab le r esi stor

d i vi d er and one vari ab le r esi stor

PART TEMP RANGE

MAX5496ETE -40°C to +85°C 16 TQFN-EP* T1655-2

MAX5497ETE -40°C to +85°C 16 TQFN-EP* T1655-2

MAX5498ETE -40°C to +85°C 16 TQFN-EP* T1655-2

MAX5499ETE -40°C to +85°C 16 TQFN-EP* T1655-2

PIN­PACKAGE

PKG CODE

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper

Digital Potentiometers

______________________________________________________________________________________ 19

Package Information

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages

.)

QFN THIN.EPS

D2

(ND-1) X e

e

D

C

PIN # 1

I.D.

(NE-1) X e

E/2

E

0.08 C

0.10 C

A

A1

A3

DETAIL A

E2/2

E2

0.10 M C A B

PIN # 1 I.D.

b

0.35x45°

D/2

D2/2

L

C

L

C

e e

L

CC

L

k

LL

DETAIL B

L

L1

e

XXXXX

MARKING

H

1

2

21-0140

PACKAGE OUTLINE,
16, 20, 28, 32, 40L THIN QFN, 5x5x0.8mm

-DRAWING NOT TO SCALE-

L

e/2

MAX5494–MAX5499

10-Bit, Dual, Nonvolatile, Linear-Taper
Digital Potentiometers

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600

© 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.

Package Information (continued)

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages

.)

COMMON DIMENSIONS

3.353.15T2855-1 3.25 3.353.15 3.25

MAX.

3.20

EXPOSED PAD VARIATIONS

3.00T2055-2 3.10

D2

NOM.MIN.

3.203.00 3.10

MIN.E2NOM. MAX.

NE

ND

PKG.

CODES

1. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994.

2. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES.

3. N IS THE TOTAL NUMBER OF TERMINALS.

4. THE TERMINAL #1 IDENTIFIER AND TERMINAL NUMBERING CONVENTION SHALL
CONFORM TO JESD 95-1 SPP-012. DETAILS OF TERMINAL #1 IDENTIFIER ARE
OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. THE TERMINAL #1
IDENTIFIER MAY BE EITHER A MOLD OR MARKED FEATURE.

5. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN

0.25 mm AND 0.30 mm FROM TERMINAL TIP.

6. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY.

7. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION.

8. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS.

9. DRAWING CONFORMS TO JEDEC MO220, EXCEPT EXPOSED PAD DIMENSION FOR T2855-1,
T2855-3, AND T2855-6.

NOTES:

SYMBOL

PKG.

N

L1

e

E

D

b

A3

A

A1

k

10. WARPAGE SHALL NOT EXCEED 0.10 mm.

JEDEC

T1655-1 3.203.00 3.10 3.00 3.10 3.20

0.70 0.800.75

4.90

4.90

0.25

0.250--

4

WHHB

4

16

0.350.30

5.10

5.105.00

0.80 BSC.

5.00

0.05

0.20 REF.

0.02

MIN. MAX.NOM.

16L 5x5

3.10

T3255-2

3.00

3.20

3.00 3.10 3.20

2.70

T2855-2 2.60 2.602.80 2.70 2.80

L

0.30 0.500.40

---

---

WHHC

20

5

5

5.00

5.00

0.30

0.55

0.65 BSC.

0.45

0.25

4.90

4.90

0.25

0.65

--

5.10

5.10

0.35

20L 5x5

0.20 REF.

0.75

0.02

NOM.

0

0.70

MIN.

0.05

0.80

MAX.

---

WHHD-1

28

7

7

5.00

5.00

0.25

0.55

0.50 BSC.

0.45

0.25

4.90

4.90

0.20

0.65

--

5.10

5.10

0.30

28L 5x5

0.20 REF.

0.75

0.02

NOM.

0

0.70

MIN.

0.05

0.80

MAX.

---

WHHD-2

32

8

8

5.00

5.00

0.40

0.50 BSC.

0.30

0.25

4.90

4.90

0.50

--

5.10

5.10

32L 5x5

0.20 REF.

0.75

0.02

NOM.

0

0.70

MIN.

0.05

0.80

MAX.

0.20 0.25 0.30

DOWN
BONDS
ALLOWED

NO

YES3.103.00 3.203.103.00 3.20T2055-3

3.103.00 3.203.103.00 3.20T2055-4

T2855-3 3.15 3.25 3.35 3.15 3.25 3.35

T2855-6 3.15 3.25 3.35 3.15 3.25 3.35

T2855-4 2.60 2.70 2.80 2.60 2.70 2.80

T2855-5 2.60 2.70 2.80 2.60 2.70 2.80

T2855-7 2.60 2.70

2.80

2.60 2.70 2.80

3.203.00 3.10T3255-3 3.203.00 3.10

3.203.00 3.10T3255-4 3.203.00 3.10

NO

NO
NO

NO

NO

NO

NO

NO

YES
YES

YES

YES

3.203.00T1655-2 3.10 3.00 3.10 3.20 YES
NO3.203.103.003.10T1655N-1 3.00 3.20

3.353.15T2055-5 3.25 3.15 3.25 3.35

YES

3.35

3.15T2855N-1 3.25 3.15 3.25 3.35

NO

3.35

3.15T2855-8 3.25 3.15 3.25 3.35

YES

3.203.10T3255N-1 3.00

NO

3.203.103.00

L

0.40

0.40

**

**
**
**

**

**

**
**
**
**

**

**
**

**
**
**

**

**

**

SEE COMMON DIMENSIONS TABLE

±0.15

11. MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY.

H

2

2

21-0140

PACKAGE OUTLINE,
16, 20, 28, 32, 40L THIN QFN, 5x5x0.8mm

-DRAWING NOT TO SCALE-

12. NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY.

3.30T4055-1 3.20 3.40 3.20 3.30 3.40

**

YES

0.0500.02

0.600.40 0.50

10

-----

0.30

40
10

0.40 0.50

5.10

4.90 5.00

0.25 0.35 0.45

0.40 BSC.

0.15

4.90

0.250.20

5.00 5.10

0.20 REF.

0.70

MIN.

0.75 0.80

NOM.

40L 5x5

MAX.

13. LEAD CENTERLINES TO BE AT TRUE POSITION AS DEFINED BY BASIC DIMENSION "e", ±0.05.