Rainbow Electronics MAX5457 User Manual

General Description

The MAX5456/MAX5457 dual, logarithmic taper digital
potentiometers feature a simple pushbutton interface
that controls volume and balance in audio applications.
Each potentiometer has 32 tap points and replaces
mechanical potentiometers. Refer to the MAX5408–
MAX5411 data sheet for SPI™ versions of the MAX5456/
MAX5457.

Use the MAX5456/MAX5457 digital inputs with momen­tary contact single-pole/single-throw (SPST) pushbutton
switches. Each input includes internal debounce cir­cuitry and a 50kΩ pullup resistor.

The MAX5456/MAX5457 advance the wiper setting once
per button push. Maxim’s proprietary SmartWiper™ con­trol eliminates the need for a microcomputer to increase
the wiper transition rate. Holding the control input low for
more than 1s advances the wiper at a rate of 4Hz for 4s
and 16Hz per second thereafter.

The MAX5456/MAX5457 provide temperature coeffi­cients of 50ppm/°C end-to-end and 5ppm/°C ratiomet­ric and a nominal resistance of 10kΩ per potentiometer.
An integrated click/pop suppression feature minimizes
the audible noise generated by wiper transitions. The
typical total harmonic distortion plus noise (THD+N) for
these devices is 0.01%.

The MAX5457 features a 3-button interface with a
MODE input that toggles between volume- and balance­control modes. An LED output indicates volume or bal­ance mode. The MAX5456 features a 4-button interface
with separate inputs for up and down volume controls
and left and right balance controls.

The MAX5456/MAX5457 are available in 16-pin QSOP
and 16-pin TQFN packages and are specified over the
extended (-40°C to +85°C) temperature range.

Applications

Stereo Volume Control

Fading and Balancing Stereo Signals

Stereo Blending and Mixing

Features

♦ SmartWiper Control Provides Accelerated Wiper

Motion

♦ Debounced Pushbutton Interface with Internal

Pullup Resistors

♦ Logarithmic Taper with 2dB Steps Between Taps

♦ Single +2.7V to +5.5V or Dual ±2.7V Supply

Operation

♦ Low 0.5µA Standby Supply Current

♦ Clickless Switching
♦ 10kΩ End-to-End Fixed Resistance Value

♦ Mute Function to -90dB (typ)

♦ Power-On Reset to -12dB Wiper Position

♦ 32 Tap Positions for Each Wiper

♦ Small 16-Pin QSOP/TQFN Packages

MAX5456/MAX5457

Stereo Audio Taper Potentiometers

with Pushbutton Interface

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

19-3490; Rev 1; 12/05

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.

Typical Application Circuits and Selector Guide appear at
end of data sheet.

SPI is a trademark of Motorola, Inc.

SmartWiper is a trademark of Maxim Integrated Products, Inc.

TOP VIEW

16

15

14

13

12

11

10

9

1

2

3

4

5

6

7

8

DN/BAL0

V

DD

V

LOGIC

GND

V

SS

H1

L1

W1

MUTE

MAX5457

QSOP

UP/BAL1

MODE

L0

MODE_IND

H0

W0

SHDN

Pin Configurations

Pin Configurations are continued at end of data sheet.

*Future product—contact factory for availability.

PART TEMP RANGE

o

MAX5456EEE -40

MAX5456ETE* -40oC to +85oC 16 TQFN T1644-4

MAX5457EEE -40oC to +85oC 16 QSOP E16-1

MAX5457ETE* -40oC to +85oC 16 TQFN T1644-4

C to +85oC 16 QSOP E16-1

PIN­PACKAGE

PKG

CODE

MAX5456/MAX5457

Stereo Audio Taper Potentiometers
with Pushbutton Interface

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VDD= V

LOGIC

= +2.7V to +5.5V, VSS= 0V, GND = 0V, V

H_

= VDD, V

L_

= VSS, TA= T

MIN

to T

MAX

. Typical values are at TA= +25°C,

unless otherwise specified.) (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.

(MAX5456) SHDN, MUTE, VOLUP, VOLDN,

BAL_ to GND.....................................-0.3V to (V

LOGIC

+ 0.3V)

(MAX5457) SHDN, MUTE, UP/BAL1, DN/BAL0, MODE,

MODE_IND to GND...........................-0.3V to (V

LOGIC

+ 0.3V)

H_, L_, and W_ to V

SS

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

V

DD

to GND..............................................................-0.3V to +6V

V

DD

to VSS................................................................-0.3V to +6V

V

LOGIC

to GND.........................................................-0.3V to +6V

V

LOGIC

to VSS...........................................................-0.3V to +6V

V

SS

to GND............................................................-3.0V to +0.3V

Peak Current into H_, L_, and W_.......................................±1mA

Average Current into H_, L_, and W_ ..............................±500µA

Input and Output Latchup Immunity...............................±200mA

Continuous Power Dissipation (T

A

= +70°C)

16-Pin QSOP (derate 8.3mW/°C above +70°C)........666.7mW

16-Pin TQFN (derate 16.9mW/°C above +70°C) ....1349.1mW

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

End-to-End Resistance R Figures 1, 2 7 10 13 kΩ

Maximum Bandwidth f

Absolute Ratio Tolerance N o l oad at the outp ut of the w i p er , W _ = - 6d B ±0.25 dB

Tap-to-Tap Tolerance ±0.1 dB

Total Harmonic Distortion Plus
Noise

Channel-to-Channel Isolation -100 dB

Interchannel Matching f = 20Hz to 20kHz, tap = -6dB ±0.5 dB

Mute Attenuation -90 dB

Power-Supply Rejection Ratio PSRR -80 dB

Wiper Resistance R

Wiper Capacitance C

H Terminal Capacitance C

L Terminal Capacitance C

End-to-End Resistance
Temperature Coefficient

Ratiometric Resistance
Temperature Coefficient

Output Noise e

PUSHBUTTON CONTACT INPUTS (UP/BAL1, DN/BAL0, MUTE, VOLUP, VOLDN, BAL0, BAL1, MODE)

Internal Pullup Resistor R

Single Pulse-Width Input t

Repetitive Input Pulse High Time t

Timeout Period t

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

CUTOFF

From H_ to W_, C

V

= 5V, VH_ = (V

DD

f = 1kHz, tap = -6dB, V

THD+N

V

= 3V, V

DD

V

= 1.5V + 1V

H_

(VDD / 2), CL = 5pF, tap = -6dB

W

W

H

L

n

PULLUP

lPW

HPW

WS

20Hz to 20kHz 0.95 µV

Figure 5 22.5 ms

Figure 5 40 ms

Click/pop suppression inactive 32 ms

SS

= 10pF 100 kHz

LOAD

/ 2) + 1V

DD

L_

= 0V, V

L_

, f = 1kHz, RL = 10kΩ to

RMS

= V

DD

= 1.5V,

RMS

,

/ 2, RL = ∞

0.01

0.23

1000 1700 Ω

10 pF

5pF

7pF

50 ppm/°C

5 ppm/°C

32 50 65 kΩ

%

RMS

MAX5456/MAX5457

Stereo Audio Taper Potentiometers

with Pushbutton Interface

_______________________________________________________________________________________ 3

Note 1: Parameters are 100% production tested at +85°C and limits through temperature are guaranteed by design.
Note 2: Supply current measured with the supply on and a button pushed.
Note 3: Supply current measured with the power on, no button pushed, and the wiper position fixed.
Note 4: This is the measured current with SHDN low and MODE_IND unconnected.

ELECTRICAL CHARACTERISTICS (continued)

(VDD= V

LOGIC

= +2.7V to +5.5V, VSS= 0V, GND = 0V, V

H_

= VDD, V

L_

= VSS, TA= T

MIN

to T

MAX

. Typical values are at TA= +25°C,

unless otherwise specified.) (Note 1)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

First Autoincrement Point 1 s

First Autoincrement Rate 4Hz

Second Autoincrement Point 4s

Second Autoincrement Rate 16 Hz

DIGITAL INPUTS (V

Input High Voltage V

Input Low Voltage V

LOGIC

> 4.5V)

IH

IL

2.4 V

0.8 V

Input Leakage Current Inputs floating ±1 µA

Input Capacitance 5pF

DIGITAL INPUTS (V

Input High Voltage V

Input Low Voltage V

LOGIC

< 4.5V)

IH

IL

0.7 x

V

L OGIC

0.3 x

V

L OGIC

V

V

Input Leakage Current Inputs floating ±1 µA

Input Capacitance 5pF

POWER SUPPLIES

Supply Voltage V

Negative Power Supply V

DD

SS

Supply-Voltage Difference VDD - V

Active Supply Current I

Standby Supply Current I

Shutdown Supply Current I

Power-Up Time t

Logic Standby Voltage V

Logic Active Supply Current I

Logic Standby Supply Current I

Logic Shutdown Current I

LOGICSTBY

LOGICSHDN

DD

STBY

SHDN

PU

LOGIC

LOGIC

(Note 2) 100 µA

V

= + 5.5V , V

D D

V

LOGIC

(Note 4) 1 µA

(Note 2) 160 µA

(Note 3) 0.5 1 µA

(Note 4) 1 µA

SS

= 0V , V

S S

= 2.7V ( N ote 3) 2 10

LOGIC

= VDD = +2.7V, VSS = -2.7V (Note 3) 0.5 1

2.7 5.5 V

-2.7 0 V

5.5 V

10 ms

2.7 V

DD

µA

V

DIGITAL OUTPUT, MODE_IND

Output Low Voltage V

OL

LOGIC

V

LOGIC

= 2.7V, I

= 5.5V, I

= 10mA 0.4

SINK

= 10mA 0.2

SINK

V

V

Output Leakage Current 0.1 10 µA

Output Capacitance 3pF

Maximum Sink Current 150 mA

MAX5456/MAX5457

Stereo Audio Taper Potentiometers
with Pushbutton Interface

4 _______________________________________________________________________________________

Typical Operating Characteristics

(VDD= V

LOGIC

= +2.7V to +5.5V, VSS= 0V, GND = 0V, VH_ = VDD, VL_ = VSS, TA= T

MIN

to T

MAX

. Typical values are at TA= +25°C,

unless otherwise specified.)

WIPER RESISTANCE vs. WIPER VOLTAGE

MAX5456/7 toc01

WIPER VOLTAGE (V)

WIPER RESISTANCE (Ω)

4.53.5 4.01.5 2.0 2.5 3.01.0

650

700

750

800

850

900

950

1000

1050

1100

1150

1200

600

0.5 5.0

VDD = V

LOGIC

= 5V

ATTENUATION vs. TAP POSITION

MAX5456/7 toc02

TAP POSITION

ATTENUATION (dB)

282420161284

-60

-50

-40

-30

-20

-10

0

-70
032

END-TO-END RESISTANCE % CHANGE

vs. TEMPERATURE

MAX5456/7 tpc03

TEMPERATURE (°C)

END-TO-END RESISTANCE CHANGE (%)

603510-15

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

-0.5

-40 85

ACTIVE SUPPLY CURRENT vs. TEMPERATURE

ACTIVE SUPPLY CURRENT (µA)

185

190

195

200

210

205

215

220

180

MAX5456/7 toc04

TEMPERATURE (°C)

603510-15-40 85

VDD = V

LOGIC

= 5.5V,

I

LOGIC

+ I

VDD

WIPER SWITCHING TRANSIENT

(TIMING OUT)

MAX5456/7 toc05a

10ms/div

5V/div

1V/div

VOLUP

WIPER TRANSITION
FROM -2dB to 0dB

VH_ = V

DD

VL_ = 0

WIPER SWITCHING TRANSIENT

(SUPPRESSION CIRCUIT ACTIVE)

MAX5456/7 toc05b

4ms/div

5V/div

2V/div

VOLUP

WIPER TRANSITION
FROM -2dB to 0dB

VH_ = SQUARE WAVE FROM
V

DD

TO VSS, VL_ = V

DD

/ 2

LOGIC SUPPLY CURRENT

vs. LOGIC SUPPLY VOLTAGE

MAX5456/7 toc06a

LOGIC SUPPLY VOLTAGE (V)

LOGIC SUPPLY CURRENT (µA)

20

40

60

80

100

120

140

160

180

200

0

ACTIVE LOGIC SUPPLY
CURRENT

5.2 5.54.2 4.73.73.22.7

MAX5456/MAX5457

Stereo Audio Taper Potentiometers

with Pushbutton Interface

_______________________________________________________________________________________ 5

Typical Operating Characteristics (continued)

(VDD= V

LOGIC

= +2.7V to +5.5V, VSS= 0V, GND = 0V, VH_ = VDD, VL_ = VSS, TA= T

MIN

to T

MAX

. Typical values are at TA= +25°C,

unless otherwise specified.)

0.05

0.10

0.15

0.20

0.25

0.30

0

LOGIC SUPPLY CURRENT

vs. LOGIC SUPPLY VOLTAGE

MAX5456/7 toc06b

LOGIC SUPPLY VOLTAGE (V)

LOGIC SUPPLY CURRENT (µA)

5.2 5.54.2 4.73.73.22.7

STANDBY LOGIC SUPPLY
CURRENT

WIPER-TO-END TERMINAL RESISTANCE

vs. TAP POSITION

MAX5456/7 toc07

TAP POSITION

NOMINAL END-TO-END RESISTANCE (%R

HL

)

24168

25

50

75

100

0

032

R

WH

R

WL

SPECTRAL NOISE DENSITY

MAX5456 toc13

FREQUENCY (kHz)

NOISE (nV

RMS

/√

Hz

)

1010.1

1

2

3

4

5

6

7

8

9

10

0

0.01 100

TOTAL HARMONIC DISTORTION PLUS NOISE

vs. FREQUENCY

100

VH_ = 2.5V ±1V
W_ SET TO -6dB,

10

20Hz TO 20kHz BANDPASS

1

0.1

THD+N (%)

0.01

0.001

0.0001
10 100,000

, VL_ = 2.5V,

P-P

LOAD = 10kΩ

NO LOAD

FREQUENCY (Hz)

DIGITAL SUPPLY CURRENT

vs. DIGITAL INPUT VOLTAGE

1000

900

800

MAX5456/7 toc09

700

600

500

400

300

DIGITAL SUPPLY CURRENT (µA)

200

100

0

10,0001000100

05

DIGITAL INPUT VOLTAGE (V)

4321

FREQUENCY RESPONSE

VH_ = 2.5V ±1V

2

= 10pF

C

L_

0

-2

RESPONSE (dB)

-4

-6

-8

0.01 1000

, VL_ = 2.5V,

P-P

W_ SET TO 0dB

W_ SET TO -6dB

FREQUENCY (kHz)

POWER-SUPPLY REJECTION RATIO

vs. FREQUENCY

0

MAX5456/7 toc10

VDD = 5V ±1V

-10

-20

-30

-40

-50

PSRR (dB)

-60

-70

-80

-90

= 2.5V, W_ SET TO -6dB

V

L_

11000

, VH_ = 5V,

P-P

FREQUENCY (kHz)

MAX5456/7 toc08

1001010.1

MAX5456/7 toc11

10010

LOGIC SUPPLY CURRENT

vs. TEMPERATURE

150

149

V

= 5.5V

LOGIC

148

147

ACTIVE LOGIC SUPPLY

146

CURRENT

145

144

143

LOGIC SUPPLY CURRENT (mA)

142

141

140

-40 85

TEMPERATURE (°C)

MAX5456/7 toc12

603510-15

MAX5456/MAX5457

Stereo Audio Taper Potentiometers
with Pushbutton Interface

6 _______________________________________________________________________________________

Pin Description

PIN

MAX5457 MAX5456

TQFN

NAME FUNCTION

13——MODE

Volume/Balance Control. Each transition from high to low toggles between volume
and balance modes. MODE is pulled high internally with a 50kΩ resistor to V

LOGIC

.

On power-up, the MAX5457 is in volume-control mode.

24——

Volume-Control/Balance-Control Mode Indicator Open-Drain Output. Connect to
an LED through a resistor to V

LOGIC

. When the LED is on, the MAX5457 is in
balance-control mode. When the LED is off, the MAX5457 is in volume-control
mode. See the Mode Indicator, MODE_IND section for more detail.

3 535 H0 Potentiometer 0 High Terminal. H0 and L0 terminals can be reversed.

4 646 L0 Potentiometer 0 Low Terminal. L0 and H0 terminals can be reversed.

5 757 W0 Potentiometer 0 Wiper Terminal

6 868SHDN

Active-Low Shutdown Input. In shutdown mode, the MAX5456/MAX5457 store the
last wiper settings. The wipers move to the L end of the resistor string, and the H
end of the resistor string disconnects from the signal input. Terminating shutdown
mode restores the wipers to their previous settings.

7 979 MUTE

Mute Input. When MUTE is low, the wiper goes to the highest attenuation setting
(see Table 1). MUTE is internally pulled up with 50kΩ to V

LOGIC

.

810810 W1 Potentiometer 1 Wiper Terminal

911911 L1 Potentiometer 1 Low Terminal. L1 and H1 terminals can be reversed.

10 12 10 12 H1 Potentiometer 1 High Terminal. H1 and L1 terminals can be reversed.

11 13 11 13 V

SS

Negative Power Supply. Bypass with 0.1µF to ground.

12 14 12 14 GND Ground

13 15 13 15 V

LOGIC

Digital Logic Power Supply. Bypass with 0.1µF to ground.

14 16 14 16 V

DD

Analog Power Supply. Bypass with 0.1µF to ground.

15 1 — —

Downward Volume/Channel 0 Balance-Control Input. In volume mode, pressing

DN/BAL0 moves both wipers towards the L terminals. In balance mode, pressing
DN/BAL0 moves the balance towards channel 0. DN/BAL0 is internally pulled up

with 50kΩ to V

LOGIC

.

16 2 — —

Upward Volume/Channel 1 Balance-Control Input. In volume mode, pressing

UP/BAL1 moves both wipers towards the H terminals. In balance mode, pressing
UP/BAL1 moves the balance towards channel 1. UP/BAL1 is internally pulled up

with 50kΩ to V

LOGIC

.

—— 1 3 BAL1

Channel 1 Balance-Control Input. Pressing BAL1 moves the balance towards
channel 1. BAL1 is internally pulled up with 50kΩ to V

LOGIC

.

—— 2 4 BAL0

Channel 0 Balance-Control Input. Pressing BAL0 moves the balance towards
channel 0. BAL0 is internally pulled up with 50kΩ to V

LOGIC

.

——15 1 VOLDN

Downward Volume-Control Input. Pressing VOLDN moves both wipers towards
the L terminals. VOLDN is internally pulled up with 50kΩ to V

LOGIC

.

——16 2 VOLUP

Upward Volume-Control Input. Pressing VOLUP moves both wipers towards the
H terminals. VOLUP is internally pulled up with 50kΩ to V

LOGIC

.

QSOP TQFN QSOP

MODE_IND

DN/BAL0

UP/BAL1