Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsLinear ICsLinear IC - Custom audio Consumer audio Pushbutton TSSOP 24

General Description

The MAX5486 dual 40kΩ logarithmic taper volume control

features a debounced pushbutton up/down interface that

controls volume and balance in audio applications. Each

potentiometer has 32 log-spaced tap points with a buffered

wiper output to replace mechanical potentiometers. An inte-

grated bias generator provides the required ((V

+ V

)/2)

bias voltage, eliminating the need for costly external op-amp

circuits in unipolar audio applications. A mode-indicator

LED output indicates volume or balance control. Five inte-

grated LED drivers indicate volume level or balance settings,

depending on the status of the mode indicator.

Use the MAX5486 digital inputs with momentary contact

single-pole/single-throw (SPST) pushbutton switches.

Each input includes internal debounced circuitry and a

pullup resistor to V

LOGIC

The MAX5486 advances the wiper setting once per but-

ton push. Maxim’s proprietary SmartWiper™ control elimi-

nates the need for a microcomputer to increase the wiper

transition rate. The accelerated auto-advance feature pro-

vides a wiper-changing rate at 4Hz for holding the control

input low for more than 250ms and at 8Hz after 500ms

and then at 11Hz after 1000ms (see Table 2).

All of the MAX5486’s pushbutton inputs are debounced.

The mute input allows a single pushbutton to change

between volume control and the -90dB (typ) mute setting.

The mode input toggles between volume and balance

control. The click-and-pop suppression feature minimizes

the audible noise generated by wiper transitions. The

typical total harmonic distortion plus noise (THD+N) for

the device is 0.003%. The MAX5486 provides a nominal

temperature coefficient of 35ppm/°C end-to-end and

5ppm/°C ratiometrically and a nominal resistance of 40kΩ

per potentiometer. The MAX5486 is available in a 24-pin

TSSOP package and is specified for operation over the

-40°C to +85°C extended temperature range.

Applications

● Home-Theater Speakers

● Desktop Speakers

● Portable Media Players

● Docking Stations

Features

● Debounced Pushbutton Interface

● SmartWiper Control Advances Wiper Rate

● Low-Power Wiper Buffers Provide 0.003% THD+N

● Bias Generator Eliminates External Op Amps

● Five-Segment LED Volume/Balance Indicator

● Clickless Switching

● Logarithmic Taper Volume Control with (31) 2dB

Steps

● Single +2.7V to +5.5V or Dual ±2.7V Supply Voltage

Operation

● Power-On Reset to -12dBFS Wiper Position

● MUTE Function Toggles to 90dB (typ)

● Low 1μA Shutdown Supply Current

● 40kΩ End-to-End Fixed Resistance Value

● Small, 24-Pin TSSOP Package

SmartWiper is a trademark of Maxim Integrated Products, Inc.

19-0672; Rev 1; 4/14

+Denotes a lead(Pb)-free/RoHS-compliant package.

PART TEMP RANGE PIN-PACKAGE

MAX5486EUG+ -40°C to +125°C 24 TSSOP

DD +

) / 2

DD +

) / 2

LOGIC

PEAK

SHDN

LEFT INPUT

RIGHT INPUT

MODEIND

MAX9761

LOGIC

LEDIND4

LEDIND3

LEDIND0

GND

MUTE

LEDIND1

LEDIND2

BIAS

BIASCAP

MAX5486

UP/BALL

DN/BALR

MODE

1MΩ

DD +

) / 2

PEAK

MAX5486 Stereo Volume Control with Pushbutton

Interface

Typical Operating Circuit

Ordering Information

Summary of content (16 pages)

PAGE 1
MAX5486 Stereo Volume Control with Pushbutton Interface General Description The MAX5486 dual 40kΩ logarithmic taper volume control features a debounced pushbutton up/down interface that controls volume and balance in audio applications. Each potentiometer has 32 log-spaced tap points with a buffered wiper output to replace mechanical potentiometers.
PAGE 2
MAX5486 Stereo Volume Control with Pushbutton Interface Absolute Maximum Ratings SHDN, MODE, MUTE, UP/BALL, and DN/BALR to GND............... -0.3V to the lower of (VLOGIC + 0.3V and +6V) H_, L_, W_, BIASCAP, BIAS to GND.......-0.3V to the lower of (VDD + 0.3V and +6V) LEDIND_, MODEIND to GND..................................-0.3V to +6V VLOGIC to GND........................................................-0.3V to +6V VDD to GND.............................................................-0.
PAGE 3
MAX5486 Stereo Volume Control with Pushbutton Interface Electrical Characteristics (continued) (VDD = +2.7V to +5.5V, VSS = GND = 0V, 2.7V ≤ (VDD - VSS) ≤ 5.5V, CBIASCAP = 1μF, BIAS = 3kΩ to GND, VLOGIC = +2.7V to VDD, VH_ = VDD - 0.15V, VL_ = (VDD - VSS)/2, SHDN = MUTE = VLOGIC, all LED outputs open, pushbutton interface inactive, VH = VBIAS + 1VRMS, VBIAS = (VDD - VSS)/2, TA = TMIN to TMAX, unless otherwise specified. Typical values are at TA = +25°C.
PAGE 4
MAX5486 Stereo Volume Control with Pushbutton Interface Electrical Characteristics (continued) (VDD = +2.7V to +5.5V, VSS = GND = 0V, 2.7V ≤ (VDD - VSS) ≤ 5.5V, CBIASCAP = 1μF, BIAS = 3kΩ to GND, VLOGIC = +2.7V to VDD, VH_ = VDD - 0.15V, VL_ = (VDD - VSS)/2, SHDN = MUTE = VLOGIC, all LED outputs open, pushbutton interface inactive, VH = VBIAS + 1VRMS, VBIAS = (VDD - VSS)/2, TA = TMIN to TMAX, unless otherwise specified. Typical values are at TA = +25°C.
PAGE 5
MAX5486 Stereo Volume Control with Pushbutton Interface Typical Operating Characteristics (VDD = +5.0V, VSS = GND = 0V, VLOGIC = +5.0V, VH_ = VDD - 0.15V, VL_ = VDD/2, CBIASCAP = 1μF.) END-TO-END RESISTANCE CHANGE (%) -10 -20 -30 -40 -50 -60 -70 0 4 8 12 16 20 24 28 VDD = VLOGIC = 5V VSS = VGND = 0V 0.10 0.05 0 -0.05 -0.10 -0.15 -0.20 -0.
PAGE 6
MAX5486 Stereo Volume Control with Pushbutton Interface Typical Operating Characteristics (continued) (VDD = +5.0V, VSS = GND = 0V, VLOGIC = +5.0V, VH_ = VDD - 0.15V, VL_ = VDD/2, CBIASCAP = 1μF.) 80 60 STANDBY CURRENT 2.0 3.0 3.5 4.0 4.5 5.0 ACTIVE SUPPLY CURRENT vs. SUPPLY VOLTAGE ACTIVE SUPPLY CURRENT vs. TEMPERATURE 1.0 0.5 0 1 2 3 4 5 2.0 VDD = VLOGIC = 5.5V VUP = 0V CROSSTALK (dB) -40 35 60 250 85 200 150 100 0.5 50 -40 -15 10 35 60 85 0 0.01 CROSSTALK vs.
PAGE 7
MAX5486 Stereo Volume Control with Pushbutton Interface Pin Description PIN NAME FUNCTION 1 VLOGIC Digital Logic Power Supply. Bypass VLOGIC to ground with a 0.1μF capacitor as close as possible to the device. 2 DN/BALR Active-Low Downward Volume/Balance Control. Press DN/BALR to decrease the volume in volume mode and move balance to the right in balance mode. DN/BALR is internally pulled high with a resistor to VLOGIC. 3 UP/BALL Active-Low Upward Volume/Balance Control.
PAGE 8
MAX5486 Stereo Volume Control with Pushbutton Interface Detailed Description VLOGIC The MAX5486 dual 40kΩ logarithmic taper digital volume control features a debounced pushbutton interface that controls volume and balance in audio applications. Each potentiometer has 32 log-spaced tap points with a buffered wiper output and replaces mechanical potentiometers. UP Mode Control (MODE) The MAX5486 MODE input toggles between volume and balance modes.
PAGE 9
MAX5486 Stereo Volume Control with Pushbutton Interface BALANCE SEPARATION MAINTAINED H_ WR WL WR WL PRESS UP TWICE WR WL WR WL WR WL PRESS DN ONCE WR WL (2a) L_ H_ PRESS UP ONCE WR NO CHANGE WL PRESS UP ONCE (2b) L_ H_ WR WL PRESS DN ONCE WR WL PRESS DN ONCE TO 2d (2c) L_ ORIGINAL BALANCE SEPARATION MAINTAINED H_ WR FROM 2c WL PRESS UP ONCE WR WL PRESS UP ONCE WR WL (2d) L_ Figures 2a–2d.
PAGE 10
MAX5486 Stereo Volume Control with Pushbutton Interface VOLUME LEVEL MAINTAINED BALANCE SHIFTS TO WL VOLUME LEVEL IS SET H_ WR WL PRESS BALL ONCE WR WL PRESS BALL ONCE WR WL (3a) L_ H_ VOLUME LEVEL MAINTAINED BALANCE SHIFTS TO WL VOLUME LEVEL IS SET BY WR WR WL PRESS BALL ONCE WR WL PRESS BALL ONCE WR WL (3b) L_ Figures 3a and 3b. Balance-Control Operation changes position, the second wiper has 126ms to change or it changes automatically.
PAGE 11
MAX5486 Stereo Volume Control with Pushbutton Interface Table 3. LED Settings in Volume Mode VOLUME POSITION WIPER ACTION LED0 LED1 LED2 LED3 LED4 0dB to -8dB 1 1 1 1 1 -10dB to -18dB 1 1 1 1 0 -20dB to -28dB 1 1 1 0 0 -30dB to -38dB 1 1 0 0 0 -40dB to -52dB 1 0 0 0 0 -54dB to mute (-90dB) 0 0 0 0 0 Table 3 shows the LED display as the wipers transition through various attenuation levels.
PAGE 12
MAX5486 Stereo Volume Control with Pushbutton Interface SWITCH SWITCH CONTACT CONTACT IS BOUNCING IS STABLE USER PRESSES PUSHBUTTON SWITCH CONTACT IS BOUNCING READY TO ACCEPT ANOTHER KEYPRESS 1 DN OR UP INPUT ACCEPTED 0 tHPW tIPW tWS DEBOUNCE BY WAITING FOR STABLE HIGH, tHPW WAIT FOR DEBOUNCE BY FIRST ZERO WAITING FOR CROSSING, tWS STABLE LOW, tIPW VH VL WIPER MOVES HERE WIPER MOTION 2dB STEPS Figure 4a. Wiper Transition Timing Diagram—Suppression Circuitry Active www.maximintegrated.
PAGE 13
MAX5486 Stereo Volume Control with Pushbutton Interface SWITCH SWITCH CONTACT CONTACT IS BOUNCING IS STABLE SWITCH CONTACT IS BOUNCING READY TO ACCEPT ANOTHER KEYPRESS 1 INPUT ACCEPTED 0 tHPW tIPW tWS DEBOUNCE BY WAITING FOR STABLE HIGH, tHPW WAIT FOR DEBOUNCE BY FIRST ZERO WAITING FOR CROSSING OR STABLE LOW, TIMEOUT, tWS tIPW VH VL WIPER MOVES HERE (tIPW + tWS) 2dB STEPS Figure 4a.
PAGE 14
MAX5486 Stereo Volume Control with Pushbutton Interface Functional Diagram VDD VDD HR BIAS BIAS GENERATOR MAX5486 BIASCAP VSS WR LR MODEIND LEDIND4 LEDIND3 LED DRIVERS HL LEDIND2 LEDIND1 LEDIND0 WL SWITCH CONTROL, CLICK-AND-POP SUPPRESSION LL UP/BALL www.maximintegrated.
PAGE 15
MAX5486 Stereo Volume Control with Pushbutton Interface Functional Diagram Chip Information TOP VIEW VLOGIC 1 PROCESS: BiCMOS + 24 GND DN/BALR 2 23 MODEIND UP/BALL 3 22 LEDIND4 MUTE 4 21 LEDIND3 MODE 5 MAX5486 20 LEDIND2 SHDN 6 19 LEDIND1 N.C. 7 18 LEDIND0 HR 8 17 HL LR 9 16 LL WR 10 15 WL BIAS 11 14 VSS BIASCAP 12 13 VDD Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages.
PAGE 16
MAX5486 Stereo Volume Control with Pushbutton Interface Revision History REVISION NUMBER REVISION DATE 0 11/06 Initial Release — 1 4/14 Updated Applications 1 DESCRIPTION PAGES CHANGED For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product.