Maxim MAX5468EUT, MAX5466EUK, MAX5464EXT, MAX5462EXT, MAX5461EXT Datasheet

General Description

The MAX5460–MAX5468 linear-taper digital potentiome­ters perform the same function as a mechanical poten­tiometer or a variable resistor. These devices consist of a
fixed resistor and a wiper contact with 32-tap points that
are digitally controlled through a 2-wire serial interface.

The MAX5462/MAX5465/MAX5468 are configured as
potentiometers. The rest of the devices in this family are
configured as variable resistors. See Pin Configurations
for part functionality.

Three resistance values are available: 10kΩ (MAX5466/
MAX5467/MAX5468), 50kΩ (MAX5463/MAX5464/
MAX5465), and 100kΩ (MAX5460/MAX5461/MAX5462).
The MAX5460–MAX5465 (100kΩ and 50kΩ) are avail­able in space-saving 5-pin and 6-pin SC70 packages.
The MAX5466/MAX5467/MAX5468 (10kΩ) are available
in 5-pin and 6-pin SOT23 packages.

Applications

LCD Screen Adjustment

Volume Control

Mechanical Potentiometer Replacement

Gain Adjustment

Line Impedance Matching

Features

♦ Miniature SC70 and SOT23 Packages

♦ 0.3µA Ultra-Low Supply Current

♦ +2.7V to +5.5V Single-Supply Operation

♦ Glitchless Switching Between Resistor Taps

♦ Power-On Reset to Midscale

♦ 2-Wire Up/Down Serial Interface

♦ 10kΩ, 50kΩ, and 100kΩ Resistance Values

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital

Potentiometers

________________________________________________________________ Maxim Integrated Products 1

Pin Configurations

Ordering Information

19-1956; Rev 2; 9/02

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.

Functional Diagram appears at end of data sheet.

FleaPoT is a trademark of Maxim Integrated Products Inc.

PART

MAX5460EXK -40°C to +85°C 5 SC70 ACA 100

MAX5461EXT -40°C to +85°C 6 SC70 AAP 100

MAX5462EXT -40°C to +85°C 6 SC70 AAQ 100

MAX5463EXK -40°C to +85°C 5 SC70 ACB 50

MAX5464EXT -40°C to +85°C 6 SC70 AAR 50

MAX5465EXT -40°C to +85°C 6 SC70 AAS 50

MAX5466EUK

MAX5467EUT -40°C to +85°C 6 SOT23 AARH 10

MAX5468EUT -40°C to +85°C 6 SOT23 AARI 10

TEMP

RANGE

-40°C to +85°C 5 SOT23 ADQQ 10

PIN­PACKAGE

TOP

MARK

R (kΩ)

TOP VIEW

15HV

DD

2

GND

MAX5460

34

MAX5463
MAX5466

SOT23, SC70

CSU/D

16HV

DD

2

GND

MAX5461

34

MAX5464
MAX5467

SOT23, SC70

L5

CSU/D

16HV

DD

2

GND

MAX5462

34

MAX5465
MAX5468

SOT23, SC70

W5

CSU/D

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital
Potentiometers

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VDD= +2.7V to +5.5V, VH= VDD, VL= 0, TA= -40°C to +85°C. Typical values are at VDD= +2.7V, TA= +25°C, unless

otherwise noted.)

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 +6V

All Other Pins to GND.................................-0.3V to (VDD+ 0.3)V

Input and Output Latch-Up Immunity.............................±200mA

Maximum Continuous Current into H, L, and W

MAX5460/MAX5461/MAX5462 (100kΩ) .......................±0.6mA

MAX5463/MAX5464/MAX5465 (50kΩ) .........................±1.3mA

MAX5466/MAX5467/MAX5468 (10kΩ) .........................±1.3mA

Continuous Power Dissipation (TA= +70°C)

5-pin SC70 (derate 3.1mW/°C above TA= +70°C)..........247mW

5-pin SOT23 (derate 7.1mW/°C above TA= +70°C)........571mW

6-pin SC70 (derate 3.1mW/°C above TA= +70°C) ..........245mW

6-pin SOT23 (derate 8.7mW/°C above T

A

= +70°C).....695.7mW

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

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

Storage Temperature Range .............................-65°C to +150°C

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

DC PERFORMANCE

Resolution 32 Taps

End-to-End Resistance

End-to-End Resistance Tempco TC

Ratiometric Resistance Tempco 5 ppm/°C

Integral Nonlinearity INL ±0.5 ±1 LSB

Differential Nonlinearity DNL ±1 LSB

Full-Scale Error ±0.1 LSB

Zero-Scale Error 1 LSB

Wiper Resistance R

DIGITAL INPUTS

Input High Voltage V

Input Low Voltage V

TIMING CHARACTERISTICS (Figures 1, 2)
U/D Mode to CS Setup t

CS to U/D Step Setup t
CS to U/D Step Hold t

U/D Step Low Period t
U/D Step High Period t

Up/Down Toggle Rate (Note 1) f

Output Settling Time (Note 2) t

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

MAX5460/MAX5461/MAX5462 75 100 125

MAX5463/MAX5464/MAX5465 37.5 50 62.5

MAX5466/MAX5467/MAX5468 7.5 10 12.5

R

MAX5460–MAX5465 600 1200

W

MAX5466/MAX5467/MAX5468 160 240

IH

IL

CU

CI

IC

IL

IH

TOGGLE

SETTLE

100kΩ var i ab l e r esi stor confi g ur ati on, C L = 10p F1

100kΩ p otenti om eter confi g ur ati on, C L = 10p F 0.25

0.7 x V

DD

25 ns

50 ns

25 ns

25 ns

25 ns

35 ppm/°C

0.3 x V

DD

1 MHz

kΩ

Ω

V

V

µs

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital

Potentiometers

_______________________________________________________________________________________ 3

Typical Operating Characteristics

(TA = +25°C, unless otherwise noted.)

Note 1: Up/Down Toggle Rate:

Note 2: Typical settling times are dependent on end-to-end resistance.
Note 3: Supply current taken while changing wiper tap, f

TOGGLE

= 1MHz.

Note 4: Supply current taken while wiper position is fixed.

ELECTRICAL CHARACTERISTICS (continued)

(VDD= +2.7V to +5.5V, VH= VDD, VL= 0, TA= -40°C to +85°C. Typical values are at VDD= +2.7V, TA= +25°C, unless

otherwise noted.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

POWER SUPPLIES

Supply Voltage V

Active Supply Current (Note 3) I

Standby Supply Current (Note 4) I

f

TOGGLE

=

1

t

SETTLE

DD

DD

SD

VDD = +5V 0.3 1 µA

2.7 5.5 V

25 µA

WIPER RESISTANCE vs. WIPER VOLTAGE

(MAX5460–MAX5465)

700

600

500

400

300

WIPER RESISTANCE (Ω)

200

100

0

0 2.01.0 3.0 4.00.5 2.51.5 3.5 4.5 5.0

VDD = +2.7V

VDD = +5V

WIPER VOLTAGE (V)

W-TO-L RESISTANCE

vs. TAP POSITION

120

100

80

60

RESISTANCE (kΩ)

40

20

0

1357911131517 19 21 23 25 27 29 31

TAP POSITION

100kΩ

50kΩ

10kΩ

MAX5460 toc01

MAX5460 toc04

WIPER RESISTANCE vs. WIPER VOLTAGE

(MAX5466/MAX5467/MAX5468)

200

180

160

140

120

100

80

60

WIPER RESISTANCE (Ω)

40

20

0

0 1.0 1.5 2.00.5 2.5 3.0 3.5 4.54.0 5.0

VDD = +2.7V

VDD = +5V

WIPER VOLTAGE (V)

SUPPLY CURRENT vs. TEMPERATURE

0.50

0.45

0.40

0.35

0.30

0.25

0.20

CURRENT (µA)

0.15

0.10

0.05

0.00

-40 10-15 35 60 85
TEMPERATURE (°C)

VDD = +5V

VDD = +2.7V

END-TO-END RESISTANCE % CHANGE

0.10

0.05

MAX5460 toc02

-0.05

-0.10

-0.15

-0.20

END-TO-END RESISTANCE % CHNAGE

-0.25

10kΩ

0

-40 10-15 35 60 85

TAP-TO-TAP SWITCHING TRANSIENT

MAX5460 toc05

U/D

2V/div

OUTPUT

W

100mV/div

vs. TEMPERATURE

50kΩ, 100kΩ

TEMPERATURE (°C)

(MAX5460)

200ns/div

MAX5460 toc03

MAX5460 toc06

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital
Potentiometers

4 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(TA = +25°C, unless otherwise noted.)

Pin Description

R-DNL ERROR vs. INPUT CODE (100kΩ)

0.08

0.06

0.04

0.02

0

-0.02

R-DNL (LSB)

-0.04

-0.06

-0.08

-0.10
010155 202530

INPUT CODE (DECIMAL)

MAX5460 toc07

R-INL ERROR vs. INPUT CODE (100kΩ)

0.10

0.08

0.06

0.04

0.02

0

R-INL (LSB)

-0.02

-0.04

-0.06

-0.08

-0.10
0 5 10 15 20 25 30

INPUT CODE (DECIMAL)

MAX5460 toc08

R-DNL ERROR vs. INPUT CODE (50kΩ)

0.04

0.02

0

-0.02

-0.04

-0.06

R-DNL (LSB)

-0.08

-0.10

-0.12

-0.14
010155202530

INPUT CODE (DECIMAL)

MAX5460 toc09

R-INL ERROR vs. INPUT CODE (50kΩ)

0.20

0.15

0.10

0.05

R-INL LSB

0

-0.05

-0.10
01520510 2530

INPUT CODE (DECIMAL)

MAX5460 toc10

-0.05

R-DNL LSB

-0.10

-0.15

-0.20

-0.25

PIN

MAX5460
MAX5463
MAX5466

MAX5461
MAX5464
MAX5467

MAX5462
MAX5465
MAX5468

111V

2 2 2 GND Ground

333U/D

444CS

5 6 6 H High Terminal of Resistor

— 5 — L Low Terminal of Resistor

—— 5 W Wiper Terminal of Resistor

R-DNL ERROR vs. INPUT CODE (10kΩ)

0.15

0.10

0.05

0

010155

INPUT CODE (DECIMAL)

NAME FUNCTION

DD

R-INL ERROR vs. INPUT CODE (10kΩ)

0.30

0.25

MAX5460 toc11

0.20

0.15

0.10

0.05

R-INL (LSB)

0

-0.05

-0.10

-0.15

25 30

20

010155202530

INPUT CODE (DECIMAL)

Power Supply

Up/Down Control Input. With CS low, a low-to-high
transition increments or decrements the wiper position.

Chip Select Input. A high-to-low CS transition
determines the mode: increment if U/D is high, or
decrement if U/D is low.

MAX5460 toc12

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital

Potentiometers

_______________________________________________________________________________________ 5

Detailed Description

The MAX5460–MAX5468 consist of a fixed resistor and a
wiper contact with 32-tap points that are digitally con­trolled through a 2-wire serial interface. Three resistance
values are available: 10kΩ (MAX5466/MAX5467/
MAX5468), 50kΩ (MAX5463/MAX5464/MAX5465), and
100kΩ (MAX5460/MAX5461/MAX5462).

The MAX5462/MAX5465/MAX5468 are designed to oper­ate as potentiometers. In this configuration, the low termi­nal of the resistor array is connected to ground (pin 2).

The MAX5461/MAX5464/MAX5467 perform as variable
resistors. In these devices, the wiper terminal and high
terminal of the resistor array are connected at pin 5.
The MAX5460/MAX5463/MAX5466 are similar variable
resistors, except the low terminal is connected to
ground (pin 2).

Digital Interface Operation

The MAX5460–MAX5468 have two modes of operation
when the serial interface is active: increment and
decrement mode. The serial interface is only active
when CS is low.

The CS and U/D inputs control the position of the wiper
along the resistor array. When CS transitions from high to
low, the part will go into increment mode if U/D is high,
and into decrement mode if U/D is low. Once the mode is
set, the device will remain in that mode until CS goes high
again. A low-to-high transition at the U/D pin will incre­ment or decrement the wiper position depending on the
current mode (Figures 1 and 2).

When the CS input transitions to high (serial interface
inactive), the value of the counter is stored and the
wiper position is maintained.

Note that when the wiper reaches the maximum (or mini­mum) tap position, the wiper will not wrap around to the
minimum (or maximum) position.

Figure 1. Serial Interface Timing Diagram, Increment Mode

Figure 2. Serial Interface Timing Diagram, Decrement Mode

CS

t

CU

t

IL

U/D

t

CI

t

SETTLE

W

t

IC

t

IH

t

SETTLE

NOTE: "W" IS NOT A DIGITAL SIGNAL. IT REPRESENTS WIPER TRANSITIONS.

CS

t

CU

U/D

t

t

SETTLE

CI

W

NOTE: "W" IS NOT A DIGITAL SIGNAL. IT REPRESENTS WIPER TRANSITIONS.

t

t

IH

t

IL

t

SETTLE

IC

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital
Potentiometers

6 _______________________________________________________________________________________

Power-On Reset

All parts in this family feature power-on reset (POR) cir­cuitry that sets the wiper position to midscale at power­up. By default, the chip is in the increment mode.

Applications Information

The MAX5460–MAX5468 are intended for circuits
requiring digitally controlled adjustable resistance,
such as LCD contrast control, where voltage biasing
adjusts the display contrast.

Controlling a Switch-Mode

LCD Bias Generator

Figure 3 shows an application where the variable resis­tor is used with a MAX1771 to make an adjustable posi­tive LCD-bias circuit. The output of the MAX1771 is a
positive voltage that is digitally controlled through the
MAX5461/MAX5464/MAX5467. Similarly, Figure 4
shows the application of the variable resistor in a digi­tally controlled negative LCD-bias circuit along with the
MAX774/MAX775/MAX776.

Alternative Positive

LCD Bias Control

Alternatively, use an op amp to provide buffering and
gain to the output of the MAX5462/MAX5465/MAX5468.
Connect the mechanical potentiometer to the positive
input of a noninverting op amp (Figure 5) to select a
portion of the input signal by digitally controlling the
wiper terminal. Figure 6 shows a similar circuit for the
MAX5461/MAX5464/MAX5467.

Adjustable Gain

Figure 7 shows how to use the variable resistor to digi­tally adjust the gain of a noninverting op amp configura­tion. Connect the MAX5461/MAX5464/MAX5467 in
series with a resistor to ground to form the adjustable
gain control of a noninverting amplifier. The MAX5460–
MAX5468 have a low 5ppm/°C ratiometric tempco that
allows for a very stable adjustable gain configuration
over temperature.

Figure 3. Adjustable Positive LCD Bias

Figure 4. Adjustable Negative LCD Bias

VIN = 5V

68µF

0.1µF

V

C3

REF

C1

= 1.5V

C2

0.1µF
2

REF

SHDN

AGND

V+

MAX1771

GND

7

5

4

6

EXT

CS

FB

MAX5461
MAX5464
MAX5467

22µH

1

8

3

V

OUT(MAX)

V

V

OUT(MIN)

V

L1

1N5817-22

N

MTD20N03HDL

R

SENSE

40mΩ

R1

= R2

R1

REF

=

R1 + R

REF

D1

C4

300µF

R2

C5

R

VAR

+ 1

R2 )

(

VAR(MAX)

V

OUT

= 12V

AT 0.5A

+ 1

V

IN

150µF

C1

C2

0.1µF

MAX5461
MAX5464
MAX5467

V

= R2

OUT(MAX)

R1 V

V

REF

V

- VFB

REF

≥ 5µA (FOR 2% GAIN-SETTING ACCURACY)

R1 + R

VAR

1

OUT V+

3

R2

R1

,

R

VAR

C3

0.1µF

V

OUT(MIN)

2

4

REF

SHDN

FB EXT

REF

= R2

R1 + R

5

6

CS

7

MAX774
MAX775
MAX776

L1

GND

8

VAR

22µH

* MAX774 = 330µF, 10V

MAX775/MAX776 = 120µF, 20V

R3

0.07Ω

Q1
Si9435

P

1N5822/
MBR340

C4*

V

OUT

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital

Potentiometers

_______________________________________________________________________________________ 7

Figure 5. Positive LCD Bias Control

Figure 6. Positive LCD Bias Control

Figure 7. Adjustable Gain Circuit

+5V

H

W

L

MAX5462
MAX5465
MAX5468

V

IN

H

L

a)

30V

V

CC

MAX5461
MAX5464
MAX5467

+5V

H

30V

V

OUT

L

MAX5461
MAX5464
MAX5467

V

OUT

V

CC

V

V

OUT

b)

IN

W

L

MAX5462
MAX5465
MAX5468

H

V

OUT

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital
Potentiometers

8 _______________________________________________________________________________________

Chip Information

TRANSISTOR COUNT: 792

UP/DN

COUNTER

V

DD

GND

CS

H

L

W

U/D

32-POSITION

DECODER

MAX5460–MAX5468

Functional Diagram

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire Digital

Potentiometers

_______________________________________________________________________________________ 9

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.)

SC70, 5L.EPS

SOT5L.EPS

MAX5460–MAX5468

32-Tap FleaPoT™, 2-Wire 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.

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

© 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.

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.)

6LSOT.EPS

SC70, 6L.EPS