MAX9724AEBC+ - Maxim Integrated Products, Inc.

General Description

The MAX9724A/MAX9724B stereo headphone ampli-

fiers are designed for portable equipment where board

space is at a premium. These devices use a unique,

patented†DirectDrive™ architecture to produce a

ground-referenced output from a single supply, elimi-

nating the need for large DC-blocking capacitors, sav-

ing cost, board space, and component height. The

MAX9724 suppresses RF radiation received by input

and supply traces acting as antennas and prevents the

amplifer from demodulating the coupled noise. The

MAX9724A offers an externally adjustable gain while

the MAX9724B has an internally preset gain of -1.5V/V.

The MAX9724A/MAX9724B deliver up to 60mW per

channel into a 32Ωload and have low 0.02% THD+N.

An 80dB at 1kHz power-supply rejection ratio (PSRR)

allows these devices to operate from noisy digital sup-

plies without an additional linear regulator.

Comprehensive click-and-pop circuitry suppresses

audible clicks and pops on startup and shutdown.

The MAX9724A/MAX9724B operate from a single 2.7V

to 5.5V supply, consume only 3.5mA of supply current,

feature short-circuit and thermal-overload protection,

and are specified over the extended -40°C to +85°C

temperature range. The devices are available in tiny 12-

bump UCSP™ (1.5mm x 2mm) and 12-pin thin QFN

(3mm x 3mm x 0.8mm) packages.

Applications

Features

♦Improved RF Noise Rejection (Up to 67dB Over

Typical Amplifiers)

♦No Bulky DC-Blocking Capacitors Required

♦ Low-Power Shutdown Mode, < 0.1µA

♦Adjustable Gain (MAX9724A) or Fixed -1.5V/V

Gain (MAX9724B)

♦Low 0.02% THD+N

♦High PSRR (80dB at 1kHz) Eliminates LDO

♦Integrated Click-and-Pop Suppression

♦2.7V to 5.5V Single-Supply Operation

♦Low Quiescent Current (3.5mA)

♦Available in Space-Saving Packages:

12-Bump UCSP (1.5mm x 2mm)

12-Pin Thin QFN (3mm x 3mm x 0.8mm)

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

19-3597; Rev 4; 6/07

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

PART GAIN

(V/V)

PIN-

PACKAGE

PKG

CODE

TOP

MARK

MAX9724AEBC+T

Adj. 12 UCSP-12

B12-1

+ADH

MAX9724AETC+

Adj. 12 TQFN-EP* T1233-1

+AAT

MAX9724BEBC+T

-1.5 12 UCSP-12

B12-1

+ADI

MAX9724BETC+

-1.5 12 TQFN-EP* T1233-1

+AAU

Note: All devices specified over the -40°C to +85°C operating

range.

+Denotes lead-free package.

T = Tape and reel.

*EP = Exposed paddle.

Cellular Phones

MP3 Players

Notebook PCs

Handheld Gaming Consoles

LEFT

AUDIO

INPUT

RIGHT

AUDIO

INPUT

SHDN

MAX9724A

LEFT

AUDIO

INPUT

RIGHT

AUDIO

INPUT

MAX9724B

SHDN

DirectDrive OUTPUTS

ELIMINATE DC-BLOCKING

CAPACITORS

DirectDrive OUTPUTS

ELIMINATE DC-BLOCKING

CAPACITORS

FIXED GAIN ELIMINATES

EXTERNAL RESISTOR

NETWORK

Block Diagrams

Pin Configurations appear at end of data sheet.

DVD Players

Smart Phones

PDAs

†U.S. Patent# 7,061,327

UCSP is a trademark of Maxim Integrated Products, Inc.

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

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.

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

PVSS to SVSS .........................................................-0.3V to +0.3V

PGND to SGND .....................................................-0.3V to +0.3V

C1P to PGND..............................................-0.3V to (VDD + 0.3V)

C1N to PGND............................................(PVSS - 0.3V) to +0.3V

PVSS and SVSS to PGND..........................................-6V to +0.3V

IN_ to SGND (MAX9724A)..........................-0.3V to (VDD + 0.3V)

IN_ to SGND (MAX9724B) .............(SVSS - 0.3V) to (VDD + 0.3V)

OUT_ to SVSS (Note 1) ....-0.3V to Min (VDD - SVSS + 0.3V, +9V)

OUT_ to VDD (Note 2) ......+0.3V to Max (SVSS - VDD - 0.3V, -9V)

SHDN to _GND.........................................................-0.3V to +6V

OUT_ Short Circuit to GND ........................................Continuous

Short Circuit between OUTL and OUTR ....................Continuous

Continuous Input Current into PVSS..................................260mA

Continuous Input Current (any other pin) .........................±20mA

Continuous Power Dissipation (TA= +70°C)

12-Bump USCP (derate 6.5mW/°C above +70°C) ........519mW

12-Pin TQFN (derate 14.7mW/°C above +70°C) .........1177mW

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

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

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

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

Bump Temperature (soldering) Reflow............................+235°C

ELECTRICAL CHARACTERISTICS

(VDD = 5V, PGND = SGND, SHDN = 5V, C1 = C2 = 1µF, RL= ∞, resistive load reference to ground; for MAX9724A gain = -1.5V/V

(RIN = 20kΩ, RF= 30kΩ); for MAX9724B gain = -1.5V/V (internally set), TA= -40°C to +85°C, unless otherwise noted. Typical values

are at TA= +25°C, unless otherwise noted.) (Note 3)

PARAMETER

SYMBOL

CONDITIONS

MIN TYP MAX

UNITS

GENERAL

Supply Voltage Range VDD Guaranteed by PSRR test 2.7 5.5 V

Quiescent Current ICC 3.5 5.5 mA

Shutdown Current

ISHDN

SHDN = SGND = PGND 0.1 1 µA

Shutdown to Full Operation tSON

180

µs

Input Impedance RIN MAX9724B, measured at IN_ 12 19 28 kΩ

Output Offset Voltage VOS (Note 4)

±1.5 ±10

VDD = 2.7V to 5.5V, TA = +25°C 69 86

f = 1kHz, 100mVP-P (Note 4) 80Power-Supply Rejection Ratio PSRR

f = 20kHz, 100mVP-P (Note 4) 65

RL = 32Ω, THD+N = 1% 30 63

Output Power (TQFN) POUT RL = 16Ω, THD+N = 1% 42 mW

RL = 32Ω, THD+N = 1% 25 45

Output Power (UCSP) POUT RL = 16Ω, THD+N = 1% 35 mW

Voltage Gain AVMAX9724B (Note 5)

-1.52 -1.5 -1.48

V/V

Channel-to-Channel Gain Tracking

MAX9724B

±0.15

RL = 1kΩ, VOUT = 2VRMS, fIN = 1kHz

0.003

RL = 32Ω, POUT = 50mW, fIN = 1kHz

0.02

Total Harmonic Distortion Plus

Noise (TQFN) (Note 6)

THD+N

RL = 16Ω, POUT = 35mW, fIN = 1kHz

0.04

RL = 1kΩ, VOUT = 2VRMS, fIN = 1kHz

0.003

RL = 32Ω, POUT = 45mW, fIN = 1kHz

0.03

Total Harmonic Distortion Plus

Noise (UCSP) (Note 6)

THD+N

RL = 16Ω, POUT = 32mW, fIN = 1kHz

0.05

BW = 22Hz to 22kHz

102

RL = 1kΩ,

VOUT = 2VRMS A-weighted

105

BW = 22Hz to 22kHz 98

Signal-to-Noise Ratio SNR RL = 32Ω,

POUT = 50mW A-weighted

101

Note 1: OUTR and OUTL should be limited to no more than 9V above SVSS, or above VDD + 0.3V, whichever limits first.

Note 2: OUTR and OUTL should be limited to no more than 9V below VDD, or below SVSS - 0.3V, whichever limits first.

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VDD = 5V, PGND = SGND, SHDN = 5V, C1 = C2 = 1µF, RL= ∞, resistive load reference to ground; for MAX9724A gain = -1.5V/V

(RIN = 20kΩ, RF= 30kΩ); for MAX9724B gain = -1.5V/V (internally set), TA= -40°C to +85°C, unless otherwise noted. Typical values

are at TA= +25°C, unless otherwise noted.) (Note 3)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Slew Rate SR 0.5 V/µs

Capacitive Drive CLNo sustained oscillations

100

Crosstalk L to R, R to L, f = 10kHz, RL = 16Ω,

POUT = 15mW -70 dB

Charge-Pump Oscillator

Frequency fOSC

190 270 400

kHz

Into shutdown

-67

Click-and-Pop Level KCP

RL = 32Ω, peak voltage,

A-weighted, 32 samples per

second (Notes 4, 7)

Out of

shutdown -64 dB

DIGITAL INPUTS (SHDN)

Input-Voltage High VINH (TQFN only) 2 V

Input-Voltage Low VINL (TQFN only) 0.8 V

Input-Voltage High VINH (UCSP only) 1.4 V

Input-Voltage Low VINL (UCSP only) 0.9 V

Input Leakage Current ±1 µA

ELECTRICAL CHARACTERISTICS

(VDD = 3V, PGND = SGND, SHDN = 3V, C1 = C2 = 1µF, RL= ∞, resistive load reference to ground; for MAX9724A gain = -1.5V/V

(RIN = 20kΩ, RF= 30kΩ); for MAX9724B gain = -1.5V/V (internally set), TA= -40°C to +85°C, unless otherwise noted. Typical values

are at TA= +25°C, unless otherwise noted.) (Note 3)

PARAMETER

SYMBOL

CONDITIONS

MIN TYP MAX

UNITS

Quiescent Current ICC 3.0 mA

Shutdown Current ISHDN SHDN = SGND = PGND 0.1 µA

f = 1kHz, 100mVP-P 80

Power-Supply Rejection Ratio

(Note 4) PSRR f = 20kHz, 100mVP-P 65 dB

RL = 32Ω, THD+N = 1% 20

Output Power (TQFN) POUT RL = 16Ω, THD+N = 1% 14 mW

RL = 32Ω, THD+N = 1% 17

Output Power (UCSP) POUT RL = 16Ω, THD+N = 1% 12 mW

RL = 1kΩ, VOUT = 2VRMS, fIN = 1kHz

0.05

RL = 32Ω, POUT = 15mW, fIN = 1kHz

0.03

Total Harmonic Distortion Plus

Noise (TQFN) (Note 6)

THD+N

RL = 16Ω, POUT = 10mW, fIN = 1kHz

0.06

RL = 1kΩ, VOUT = 2VRMS, fIN = 1kHz

0.003

RL = 32Ω, POUT = 15mW, fIN = 1kHz

0.04

Total Harmonic Distortion Plus

Noise (UCSP) (Note 6)

THD+N

RL = 16Ω, POUT = 10mW, fIN = 1kHz

0.06

Note 3: All specifications are 100% tested at TA= +25°C; temperature limits are guaranteed by design.

Note 4: The amplifier inputs are AC-coupled to GND.

Note 5: Gain for the MAX9724A is adjustable.

Note 6: Measurement bandwidth is 22Hz to 22kHz.

Note 7: Test performed with a 32Ωresistive load connected to GND. Mode transitions are controlled by SHDN. KCP level is calculated

as 20log[(peak voltage during mode transition, no input signal)/(peak voltage under normal operation at rated power level)].

Units are expressed in dB.

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

4 _______________________________________________________________________________________

Typical Operating Characteristics

(VDD = 5V, PGND = SGND = 0V, SHDN = VDD, C1 = C2 = 1µF, RL= ∞, gain = -1.5V/V (RIN = 20kΩ, RF= 30kΩfor the MAX9724A),

THD+N measurement bandwidth = 22Hz to 22kHz, both outputs driven in phase, TA= +25°C, unless otherwise noted.)

100

010203040

0.1

0.01

0.001

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER (TQFN)

MAX9724 toc01

OUTPUT POWER (mW)

THD+N (%)

VDD = 3V

RL = 16Ω

fIN = 1kHz

fIN = 20Hz

fIN = 10kHz

0 5 15 2510 20 30

0.1

0.01

0.001

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER (UCSP)

MAX9724 toc02

OUTPUT POWER (mW)

THD+N (%)

VDD = 3V

RL = 16Ω

fIN = 1kHz

fIN = 20Hz

fIN = 10kHz

100

010 3020 40 50

0.1

0.01

0.001

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER (TQFN)

MAX9724toc03

OUTPUT POWER (mW)

THD+N (%)

VDD = 3V

RL = 32Ω

fIN = 1kHz

fIN = 20Hz

fIN = 10kHz

05 1510 20 25 30 35 40

0.1

0.01

0.001

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER (USCP)

MAX9724toc04

OUTPUT POWER (mW)

THD+N (%)

VDD = 3V

RL = 32Ω

fIN = 1kHz fIN = 10kHz

fIN = 20Hz

100

020 6040 80 100

0.1

0.01

0.001

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER (TQFN)

MAX9724 toc05

OUTPUT POWER (mW)

THD+N (%)

VDD = 5V

RL = 16Ω

fIN = 1kHz

fIN = 20Hz

fIN = 10kHz

010 3020 40 50 60 70 80

0.1

0.01

0.001

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER (UCSP)

MAX9724 toc06

OUTPUT POWER (mW)

THD+N (%)

VDD = 5V

RL = 16Ω

fIN = 1kHz

fIN = 20Hz

fIN = 10kHz

100

020 6040 80 120

0.1

0.01

0.001

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER (TQFN)

MAX9724 toc07

OUTPUT POWER (mW)

THD+N (%)

100

VDD = 5V

RL = 32Ω

fIN = 1kHz

fIN = 20Hz

fIN = 10kHz

05025 75 100

0.1

0.01

0.001

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER (UCSP)

MAX9724 toc08

OUTPUT POWER (mW)

THD+N (%)

VDD = 5V

RL = 32Ω

fIN = 1kHz

fIN = 20Hz

fIN = 10kHz

10 1k100 10k 100k

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY (TQFN)

MAX9724 toc09

FREQUENCY (Hz)

THD+N (%)

0.1

0.001

0.01

VDD = 3V

RL = 16Ω

POUT = 5mW

POUT = 10mW

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

_______________________________________________________________________________________ 5

Typical Operating Characteristics (continued)

(VDD = 5V, PGND = SGND = 0V, SHDN = VDD, C1 = C2 = 1µF, RL= ∞, gain = -1.5V/V (RIN = 20kΩ, RF= 30kΩfor the MAX9724A),

THD+N measurement bandwidth = 22Hz to 22kHz, both outputs driven in phase, TA= +25°C, unless otherwise noted.)

10 1k100 10k 100k

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY (UCSP)

MAX9724 toc10

FREQUENCY (Hz)

THD+N (%)

0.1

0.001

0.01

VDD = 3V

RL = 16ΩPOUT = 5mW

POUT = 10mW

10 1k100 10k 100k

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY (TQFN)

MAX9724 toc11

FREQUENCY (Hz)

THD+N (%)

0.1

0.001

0.01

VDD = 3V

RL = 32Ω

POUT = 8mW

POUT = 15mW

10 1k100 10k 100k

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY (UCSP)

MAX9724 toc12

FREQUENCY (Hz)

THD+N (%)

0.1

0.001

0.01

VDD = 3V

RL = 32Ω

POUT = 8mW

POUT = 13mW

10 1k100 10k 100k

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY (TQFN)

MAX9724 toc13

FREQUENCY (Hz)

THD+N (%)

0.1

0.001

0.01

VDD = 5V

RL = 16Ω

POUT = 20mW

POUT = 37mW

10 1k100 10k 100k

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY (UCSP)

MAX9724 toc14

FREQUENCY (Hz)

THD+N (%)

0.1

0.001

0.01

VDD = 5V

RL = 16Ω

POUT = 20mW

POUT = 32mW

10 1k100 10k 100k

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY (TQFN)

MAX9724 toc15

FREQUENCY (Hz)

THD+N (%)

0.1

0.001

0.01

VDD = 5V

RL = 32Ω

POUT = 50mW

POUT = 30mW

10 1k100 10k 100k

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY (UCSP)

MAX9724 toc16

FREQUENCY (Hz)

THD+N (%)

0.1

0.001

0.01

VDD = 5V

RL = 32Ω

POUT = 45mW

POUT = 20mW

2.5 3.5 4.03.0 4.5 5.0 5.5

OUTPUT POWER

vs. SUPPLY VOLTAGE (TQFN)

MAX9724 toc17

SUPPLY VOLTAGE (V)

OUTPUT POWER (mW)

fIN = 1kHz

RL = 16Ω

1% THD+N

10% THD+N

2.5 3.5 4.03.0 4.5 5.0 5.5

OUTPUT POWER

vs. SUPPLY VOLTAGE (UCSP)

MAX9724 toc18

SUPPLY VOLTAGE (V)

OUTPUT POWER (mW)

fIN = 1kHz

RL = 16Ω

1% THD+N

10% THD+N

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VDD = 5V, PGND = SGND = 0V, SHDN = VDD, C1 = C2 = 1µF, RL= ∞, gain = -1.5V/V (RIN = 20kΩ, RF= 30kΩfor the MAX9724A),

THD+N measurement bandwidth = 22Hz to 22kHz, both outputs driven in phase, TA= +25°C, unless otherwise noted.)

100

120

2.5 3.5 4.03.0 4.5 5.0 5.5

OUTPUT POWER

vs. SUPPLY VOLTAGE (TQFN)

MAX9724 toc19

SUPPLY VOLTAGE (V)

OUTPUT POWER (mW)

fIN = 1kHz

RL = 32Ω

1% THD+N

10% THD+N

100

120

2.5 3.5 4.03.0 4.5 5.0 5.5

OUTPUT POWER

vs. SUPPLY VOLTAGE (UCSP)

MAX9724 toc20

SUPPLY VOLTAGE (V)

OUTPUT POWER (mW)

fIN = 1kHz

RL = 32Ω

1% THD+N

10% THD+N

10 100 1000

OUTPUT POWER

vs. LOAD RESISTANCE (TQFN)

MAX9724 toc21

LOAD RESISTANCE (Ω)

OUTPUT POWER (mW)

VDD = 3V

fIN = 1kHz

1% THD+N

10% THD+N

10 100 1000

OUTPUT POWER

vs. LOAD RESISTANCE (UCSP)

MAX9724 toc22

LOAD RESISTANCE (Ω)

OUTPUT POWER (mW)

VDD = 3V

fIN = 1kHz

THD+N = 1%

THD+N = 10%

100

10 100

OUTPUT POWER

vs. LOAD RESISTANCE (TQFN)

MAX9724 toc23

LOAD RESISTANCE (Ω)

OUTPUT POWER (mW)

THD+N = 1%

VDD = 5V

fIN = 1kHz

THD+N = 10%

100

10 100

OUTPUT POWER

vs. LOAD RESISTANCE (UCSP)

MAX9724 toc24

LOAD RESISTANCE (Ω)

OUTPUT POWER (mW)

THD+N = 1%

VDD = 5V

fIN = 1kHz

THD+N = 10%

150

100

200

250

POWER DISSIPATION

vs. OUTPUT POWER (TQFN)

MAX9724t oc25

OUTPUT POWER (mW)

POWER DISSIPATION (mW)

04020 60 80

VDD = 3V

fIN = 1kHz

POUT = POUTL + POUTR

OUTPUTS IN PHASE

RL = 16Ω

RL = 32Ω

100

120

140

160

POWER DISSIPATION

vs. OUTPUT POWER (UCSP)

MAX9724t oc26

OUTPUT POWER (mW)

POWER DISSIPATION (mW)

010152025305404535 50

VDD = 3V

fIN = 1kHz

POUT = POUTL + POUTR

OUTPUTS IN PHASE

RL = 16Ω

RL = 32Ω

-120

10 100 10k 100k

POWER-SUPPLY REJECTION RATIO

vs. FREQUENCY

-100

-80

-40

-60

-20

MAX9724 toc27

FREQUENCY (Hz)

PSRR (dB)

VDD = 5V

VDD = 3V

RL = 32Ω

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

_______________________________________________________________________________________ 7

-120

10 100 10k 100k

CROSSTALK vs. FREQUENCY

-100

-80

-40

-60

-20

MAX9724 toc28

FREQUENCY (Hz)

CROSSTALK (dB)

RIGHT TO LEFT

LEFT TO RIGHT

POUT = 15mW

RL = 16Ω

0 100 15050

OUTPUT POWER vs. LOAD RESISTANCE AND

CHARGE-PUMP CAPACITOR SIZE (TQFN)

MAX9724 toc29

LOAD RESISTANCE (Ω)

OUTPUT POWER (mW)

VDD = 5V

fIN = 1kHz

THD+N = 1%

C1 = C2 = 2.2µFC1 = C2 = 1µF

C1 = C2 = 0.47µF

0 100 15050

OUTPUT POWER vs. LOAD RESISTANCE AND

CHARGE-PUMP CAPACITOR SIZE (UCSP)

MAX9724 toc30

LOAD RESISTANCE (Ω)

OUTPUT POWER (mW)

VDD = 5V

fIN = 1kHz

THD+N = 1%

C1 = C2 = 2.2µF

C1 = C2 = 1µF

C1 = C2 = 0.47µF

-140

-110

-130

-70

-90

-50

-120

-80

-100

-60

-40

0 5 10 15 20

OUTPUT SPECTRUM vs. FREQUENCY

MAX9724 toc31

FREQUENCY (kHz)

AMPLITUDE (dBV)

RL = 32Ω

VDD = 3V

fIN = 1kHz

VOUT = -60dBV

2.8

3.1

2.9

3.3

3.0

3.4

3.2

3.5

2.5 3.0 4.03.5 4.5 5.0 5.5

SUPPLY CURRENT vs. SUPPLY VOLTAGE

MAX9724 toc32

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (mA)

NO LOAD

INPUTS

GROUND

SHUTDOWN CURRENT

vs. SUPPLY VOLTAGE (TQFN)

MAX9724 toc33

SUPPLY VOLTAGE (V)

SHUTDOWN CURRENT (nA)

5.04.54.03.53.0

100

120

140

2.5 5.5

NO LOAD INPUTS GND

Typical Operating Characteristics (continued)

(VDD = 5V, PGND = SGND = 0V, SHDN = VDD, C1 = C2 = 1µF, RL= ∞, gain = -1.5V/V (RIN = 20kΩ, RF= 30kΩfor the MAX9724A),

THD+N measurement bandwidth = 22Hz to 22kHz, both outputs driven in phase, TA= +25°C, unless otherwise noted.)

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

8 _______________________________________________________________________________________

Pin Description

TQFN

UCSP NAME

FUNCTION

1 C1 C1P Flying Capacitor Positive Terminal. Connect a 1µF ceramic capacitor from C1P to C1N.

2C2

PGND

Power Ground. Connect to SGND.

3 C3 C1N Flying Capacitor Negative Terminal. Connect a 1µF ceramic capacitor from C1P to C1N.

4C4PV

SS Charge-Pump Output. Connect to SVSS and bypass with a 1µF ceramic capacitor to PGND.

5A2

SHDN

Active-Low Shutdown Input

6 B3 INL Left-Channel Input

7A1

SGND

Signal Ground. Connect to PGND.

8 B2 INR Right-Channel Input

9B4SV

SS Amplifier Negative Supply. Connect to PVSS.

10 A3

OUTR

Right-Channel Output

11 A4

OUTL

Left-Channel Output

12 B1 VDD Positive Power-Supply Input. Bypass with a 1µF capacitor to PGND.

EP — EP Exposed Paddle. Internally connected to SVSS. Connect to SVSS or leave unconnected.

EXITING SHUTDOWN

MAX9724 toc34

VSHDN

5V/div

VOUT_

500mV/div

VIN_

1V/div

40µs/div

ENTERING SHUTDOWN

MAX9724 toc35

VSHDN

5V/div

VOUT_

500mV/div

VIN_

1V/div

20µs/div

Typical Operating Characteristics (continued)

(VDD = 5V, PGND = SGND = 0V, SHDN = VDD, C1 = C2 = 1µF, RL= ∞, gain = -1.5V/V (RIN = 20kΩ, RF= 30kΩfor the MAX9724A),

THD+N measurement bandwidth = 22Hz to 22kHz, both outputs driven in phase, TA= +25°C, unless otherwise noted.)

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

_______________________________________________________________________________________ 9

Detailed Description

The MAX9724A/MAX9724B stereo headphone ampli-

fiers feature Maxim’s patented DirectDrive architecture,

eliminating the large output-coupling capacitors

required by conventional single-supply headphone

amplifiers. The device consists of two 60mW Class AB

headphone amplifiers, undervoltage lockout

(UVLO)/shutdown control, charge pump, and compre-

hensive click-and-pop suppression circuitry (see the

Functional Diagram/Typical Operating Circuits). The

charge pump inverts the positive supply (VDD), creat-

ing a negative supply (PVSS). The headphone ampli-

fiers operate from these bipolar supplies with their

outputs biased about PGND (Figure 1). The benefit of

this PGND bias is that the amplifier outputs do not have

a DC component. The large DC-blocking capacitors

required with conventional headphone amplifiers are

unnecessary, conserving board space, reducing sys-

tem cost, and improving frequency response. The

MAX9724A/MAX9724B feature an undervoltage lockout

that prevents operation from an insufficient power sup-

ply and click-and-pop suppression that eliminates audi-

ble transients on startup and shutdown. The

MAX9724A/MAX9724B also feature thermal-overload

and short-circuit protection.

DirectDrive

Conventional single-supply headphone amplifiers have

their outputs biased about a nominal DC voltage (typi-

cally half the supply) for maximum dynamic range.

Large-coupling capacitors are needed to block this DC

bias from the headphone. Without these capacitors, a

significant amount of DC current flows to the head-

phone, resulting in unnecessary power dissipation and

possible damage to both headphone and headphone

amplifier.

Maxim’s patented DirectDrive architecture uses a

charge pump to create an internal negative supply volt-

age, allowing the MAX9724A/MAX9724B outputs to be

biased about GND. With no DC component, there is no

need for the large DC-blocking capacitors. The

MAX9724A/MAX9724B charge pumps require two

small ceramic capacitors, conserving board space,

reducing cost, and improving the frequency response

of the headphone amplifier. See the Output Power vs.

Load Resistance and Charge-Pump Capacitor Size

graph in the Typical Operating Characteristics for

details of the possible capacitor sizes. There is a low

DC voltage on the amplifier outputs due to amplifier off-

set. However, the offsets of the MAX9724A/MAX9724B

are typically 1.5mV, which, when combined with a 32Ω

load, results in less than 47µA of DC current flow to the

headphones.

Charge Pump

The MAX9724A/MAX9724B feature a low-noise charge

pump. The 270kHz switching frequency is well beyond

the audio range and does not interfere with audio sig-

nals. The switch drivers feature a controlled switching

speed that minimizes noise generated by turn-on and

turn-off transients. The di/dt noise caused by the para-

sitic bond wire and trace inductance is minimized by

limiting the switching speed of the charge pump.

Although not typically required, additional high-fre-

quency noise attenuation can be achieved by increas-

ing the value of C2 (see the Functional Diagram/Typical

Operating Circuits).

RF Susceptibility

Modern audio systems are often subject to RF radiation

from sources like wireless networks and cellular phone

networks. Although the RF radiation is out of the audio

band, many signals, in particular GSM signals, contain

bursts or modulation at audible frequencies. Most ana-

log amplifiers demodulate the low-frequency envelope,

adding noise to the audio signal. The architecture of

VDD

-VDD

GND

VOUT

CONVENTIONAL DRIVER-BIASING SCHEME

DirectDrive BIASING SCHEME

VDD/2

VDD

GND

VOUT

2VDD

Figure 1. Conventional Driver Output Waveform vs.

MAX9724A/MAX9724B Output Waveform

MAX9724A/MAX9724B

the MAX9724 addresses the problem of the RF suscep-

tibility by rejecting RF noise and preventing it from cou-

pling into the audio band.

The RF susceptibility of an amplifier can be measured

by placing the amplifier in an isolated chamber and sub-

jecting it to an electric field of known strength. If the

electric field is modulated with an audio band signal, a

percentage of the modulated signal will be demodulat-

ed and amplified by the device in the chamber. Figure 2

shows the signal level at the outputs of an unoptimized

amplifier and the MAX9724. The test conditions are

shown in Table 1.

Click-and-Pop Suppression

In conventional single-supply audio amplifiers, the out-

put-coupling capacitor contributes significantly to audi-

ble clicks and pops. Upon startup, the amplifier charges

the coupling capacitor to its bias voltage, typically half

the supply. Likewise, on shutdown, the capacitor is dis-

charged. This results in a DC shift across the capacitor,

which appears as an audible transient at the speaker.

Since the MAX9724A/ MAX9724B do not require output-

coupling capacitors, this problem does not arise.

Additionally, the MAX9724A/MAX9724B feature exten-

sive click-and-pop suppression that eliminates any audi-

ble transient sources internal to the device.

Typically, the output of the device driving the

MAX9724A/MAX9724B has a DC bias of half the supply

voltage. At startup, the input-coupling capacitor is

charged to the preamplifier’s DC-bias voltage through

the input and feedback resistors of the MAX9724A/

MAX9724B, resulting in a DC shift across the capacitor

and an audible click/pop. Delay the rise of SHDN 4 to 5

time constants based on RIN and CIN, relative to the

startup of the preamplifier, to eliminate clicks-and-pops

caused by the input filter.

Shutdown

The MAX9724A/MAX9724B feature a <0.1µA, low-

power shutdown mode that reduces quiescent current

consumption and extends battery life for portable appli-

cations. Drive SHDN low to disable the amplifiers and

the charge pump. In shutdown mode, the amplifier out-

put impedance is set to 14kΩ||RF(RFis 30kΩfor the

MAX9724B). The amplifiers and charge pump are

enabled once SHDN is driven high.

Applications Information

Power Dissipation

Under normal operating conditions, linear power ampli-

fiers can dissipate a significant amount of power. The

maximum power dissipation for each package is given

in the Absolute Maximum Ratings section under

Continuous Power Dissipation or can be calculated by

the following equation:

PTT

DISSPKG MAX J MAX A

() ()

=−

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

10 ______________________________________________________________________________________

TEST PARAMETER SETTING

RF Field Strength 50V/m

RF Modulation Type Sine wave

RF Modulation Index 100%

RF Modulation Frequency 1kHz

Table 1. RF Susceptibility Test Conditions

MAX9724 fig02

RF CARRIER FREQUENCY (MHz)

AMPLIFIER OUTPUT AMPLITUDE (dBV)

1600 21001100

600

-80

-60

-40

-20

RF SUSCEPTIBLE

AMPLIFIER

MAX9724

62dB IMPROVEMENT

AT 850MHz 39dB IMPROVEMENT

AT 900MHz

67dB IMPROVEMENT

AT 1800MHz

49dB IMPROVEMENT

AT 1900MHz

-100

100 2600

Figure 2. RF Susceptibility of the MAX9724 and a Typical Headphone Amplifier

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

______________________________________________________________________________________ 11

where TJ(MAX) is +150°C, TAis the ambient tempera-

ture, and θJA is the reciprocal of the derating factor in

°C/W as specified in the Absolute Maximum Ratings

section. For example, θJA of the thin QFN package is

+68°C/W, and 154.2°C/W for the UCSP package.

The MAX9724A/MAX9724B have two power dissipation

sources; a charge pump and the two output amplifiers.

If power dissipation for a given application exceeds the

maximum allowed for a particular package, reduce

VDD, increase load impedance, decrease the ambient

temperature, or add heatsinking to the device. Large

output, supply, and ground traces decrease θJA, allow-

ing more heat to be transferred from the package to the

surrounding air.

Thermal-overload protection limits total power dissipa-

tion in the MAX9724A/MAX9724B. When the junction

temperature exceeds +150°C, the thermal protection

circuitry disables the amplifier output stage. The ampli-

fiers are enabled once the junction temperature cools

by approximately 12°C. This results in a pulsing output

under continuous thermal-overload conditions.

Output Dynamic Range

Dynamic range is the difference between the noise floor

of the system and the output level at 1% THD+N.

Determine the system’s dynamic range before setting the

maximum output gain. Output clipping occurs if the out-

put signal is greater than the dynamic range of the sys-

tem. The DirectDrive architecture of the MAX9724A/

MAX9724B has increased the dynamic range compared

to other single-supply amplifiers.

Maximum Output Swing

VDD < 4.35V

If the output load impedance is greater than 1kΩ, the

MAX9724A/MAX9724B can swing within a few millivolts

of their supply rail. For example, with a 3.3V supply, the

output swing is 2VRMS, or 2.83V peak while maintaining

a low 0.003% THD+N. If the supply voltage drops to

3V, the same 2.83V peak has only 0.05% THD+N.

VDD > 4.35V

Internal device structures limit the maximum voltage

swing of the MAX9724A/MAX9724B when operated at

supply voltages greater than 4.35V. The output must not

be driven such that the peak output voltage exceeds the

opposite supply voltage by 9V. For example, if VDD =

5V, the charge pump sets PVSS = -5V. Therefore, the

peak output swing must be less than ±4V to prevent

exceeding the absolute maximum ratings.

UVLO

The MAX9724A/MAX9724B feature an undervoltage

lockout (UVLO) function that prevents the device from

operating if the supply voltage is less than 2.7V. This fea-

ture ensures proper operation during brownout condi-

tions and prevents deep battery discharge. Once the

supply voltage exceeds the UVLO threshold, the

MAX9724A/MAX9724B charge pump is turned on and

the amplifiers are powered, provided that SHDN is high.

Component Selection

Input-Coupling Capacitor

The input capacitor (CIN), in conjunction with the input

resistor (RIN), forms a highpass filter that removes the

DC bias from an incoming signal (see the Functional

Diagram/Typical Operating Circuits). The AC-coupling

capacitor allows the device to bias the signal to an opti-

mum DC level. Assuming zero-source impedance, the -

3dB point of the highpass filter is given by:

Choose the CIN such that f-3dB is well below the lowest

frequency of interest. Setting f-3dB too high affects the

device’s low-frequency response. Use capacitors

whose dielectrics have low-voltage coefficients, such

as tantalum or aluminum electrolytic. Capacitors with

high-voltage coefficients, such as ceramics, can result

in increased distortion at low frequencies.

Charge-Pump Capacitor Selection

Use ceramic capacitors with a low ESR for optimum

performance. For optimal performance over the extend-

ed temperature range, select capacitors with an X7R

dielectric. Table 2 lists suggested manufacturers.

fRC

dB IN IN

−=

2π

SUPPLIER PHONE FAX WEBSITE

Taiyo Yuden 800-348-2496 847-925-0899 www.t-yuden.com

TDK 847-803-6100 847-390-4405 www.component.tdk.com

Murata 770-436-1300 770-436-3030 www.murata.com

Table 2. Suggested Capacitor Manufacturers

MAX9724A/MAX9724B

Flying Capacitor (C1)

The value of the flying capacitor (see the Functional

Diagram/Typical Operating Circuits) affects the charge

pump’s load regulation and output resistance. A C1

value that is too small degrades the device’s ability to

provide sufficient current drive, which leads to a loss of

output voltage. Increasing the value of C1 improves load

regulation and reduces the charge-pump output resis-

tance to an extent. See the Output Power vs. Load

Resistance and Charge-Pump Capacitor Size graph in

the Typical Operating Characteristics. Above 1µF, the

on-resistance of the switches and the ESR of C1 and C2

dominate.

Hold Capacitor (C2)

The hold capacitor value (see the Functional

Diagram/Typical Operating Circuits) and ESR directly

affect the ripple at PVSS. Increasing the value of C2

reduces output ripple. Likewise, decreasing the ESR of

C2 reduces both ripple and output resistance. Lower

capacitance values can be used in systems with low

maximum output power levels. See the Output Power

vs. Load Resistance and Charge-Pump Capacitor Size

graph in the Typical Operating Characteristics.

Power-Supply Bypass Capacitor (C3)

The power-supply bypass capacitor (see the Functional

Diagram/Typical Operating Circuits) lowers the output

impedance of the power supply, and reduces the

impact of the MAX9724A/MAX9724B’s charge-pump

switching transients. Bypass VDD with C3, the same

value as C1, and place it physically close to the VDD

and PGND pins.

Amplifier Gain

The gain of the MAX9724B amplifier is internally set to

-1.5V/V. All gain-setting resistors are integrated into the

device, reducing external component count. The inter-

nally set gain, in combination with DirectDrive, results in

a headphone amplifier that requires only five small

capacitors to complete the amplifier circuit: two for the

charge pump, two for audio input coupling, and one for

power-supply bypassing (see the Functional

Diagram/Typical Operating Circuits).

The gain of the MAX9724A amplifier is set externally as

shown in Figure 3, the gain is:

AV= -RF/RIN (V/V)

Choose feedback resistor values in the tens of kΩ

range. Lower values may cause excessive power dissi-

pation and require impractically small values of RIN for

large gain settings. The high-impedance state of the

outputs can also be degraded during shutdown mode

if an inadequate feedback resistor is used since the

equivalent output impedance during shutdown is

14kΩ||Rf(RFis equal to 30kΩfor the MAX9724B). The

source resistance of the input device may also need to

be taken into consideration. Since the effective value of

RIN is equal to the sum of the source resistance of the

input device and the value of the input resistor connect-

ed to the inverting terminal of the headphone amplifier

(20kΩfor the MAX9724B), the overall closed-loop gain

of the headphone amplifier can be reduced if the input

resistor is not significantly larger than the source resis-

tance of the input device.

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

12 ______________________________________________________________________________________

LEFT

AUDIO

INPUT

RIGHT

AUDIO

INPUT

OUTL

INL

INR

OUTR

MAX9724A

RIN

Figure 3. Gain Setting for the MAX9724A

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

______________________________________________________________________________________ 13

Lineout Amplifier and Filter Block

The MAX9724A can be used as an audio line driver

capable of providing 2VRMS into 10kΩloads with a sin-

gle 5V supply (see Figure 4 for the RMS Output Voltage

vs. Supply Voltage plot). 2VRMS is a popular audio line

level, first used in CD players, but now common in DVD

and set-top box (STB) interfacing standards. A 2VRMS

sinusoidal signal equates to approximately 5.7VP-P,

which means that the audio system designer cannot

simply run the lineout stage from a (typically common)

5V supply—the resulting output swing would be inade-

quate. A common solution to this problem is to use op

amps driven from split supplies (±5V typically), or to

use a high-voltage supply rail (9V to 12V). This can

mean adding extra cost and complexity to the system

power supply to meet this output level requirement.

Having the ability to derive 2VRMS from a 5V supply, or

even 3.3V supply, can often simplify power-supply

design in some systems.

When the MAX9724A is used as a line driver to provide

outputs that feed stereo equipment (receivers, STBs,

notebooks, and desktops) with a digital-to-analog con-

verter (DAC) used as an audio input source, it is often

desirable to eliminate any high-frequency quantization

noise produced by the DAC output before it reaches

the load. This high-frequency noise can cause the input

stages of the line-in equipment to exceed slew-rate lim-

itations or create excessive EMI emissions on the

cables between devices.

LEFT

AUDIO

INPUT

RIGHT

AUDIO

INPUT

OUTL

INL

INR

OUTR

MAX9724A

7.5kΩ 7.5kΩ

15kΩ

10kΩ

15kΩ

1.2nF

220pF

LINE IN DEVICE

STEREO

DAC

1µF

Figure 5. MAX9724A Line Out Amplifier and Filter Block Configuration

RMS OUTPUT VOLTAGE

vs. SUPPLY VOLTAGE

SUPPLY VOLTAGE (V)

RMS OUTPUT VOLTAGE (V)

5.04.54.03.53.0

2.0

2.5

3.0

3.5

1.5

2.5 5.5

RL = 10kΩ

1% THD+N

fIN = 1kHz

RL = 1kΩ

1% THD+N

LIMITED BY

ABS. MAXIMUM

RATINGS

Figure 4. RMS Output Voltage vs. Supply Voltage

To suppress this noise, and to provide a 2VRMS stan-

dard audio output level from a single 5V supply, the

MAX9724A can be configured as a line driver and

active lowpass filter. Figure 5 shows the MAX9724A

connected as 2-pole Rauch/multiple feedback filter with

a passband gain of 6dB and a -3dB (below passband)

cutoff frequency of approximately 27kHz (see Figure 6

for the Gain vs. Frequency plot).

Layout and Grounding

Proper layout and grounding are essential for optimum

performance. Connect PGND and SGND together at a

single point on the PC Board. Connect PVSS to SVSS

and bypass with a 1µF capacitor. Place the power-sup-

ply bypass capacitor and the charge-pump hold

capacitor as close to the MAX9724 as possible. Route

PGND and all traces that carry switching transients

away from SGND and the audio signal path. The thin

QFN package features an exposed paddle that

improves thermal efficiency. Ensure that the exposed

paddle is electrically isolated from PGND, SGND,

and VDD. Connect the exposed paddle to SVSS only

when the board layout dictates that the exposed

paddle cannot be left floating.

UCSP Applications Information

For the latest application details on UCSP construction,

dimensions, tape carrier information, printed circuit

board techniques, bump-pad layout, and recommend-

ed reflow temperature profile, as well as the latest infor-

mation on reliability testing results, refer to the

Application Note UCSP—A Wafer-Level Chip-Scale

Package available on Maxim’s website at www.maxim-

ic.com/ucsp.

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

14 ______________________________________________________________________________________

MAX9724A ACTIVE FILTER GAIN

vs. FREQUENCY

FREQUENCY (Hz)

GAIN (dB)

100k10k

-30

-25

-20

-15

-10

-5

-35

1k 1M

RL = 10kΩ

Figure 6. Frequency Response of Active Filter of Figure 4

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

______________________________________________________________________________________ 15

MAX9710

OUTR+

OUTR-

OUTL-

OUTL+

INR

INL

BIAS

PVDD

VDD

SHDN

15kΩ

VDD

0.1µF

1µF

0.1µF

1µF

MAX9724B

0.1µF

OUTL

OUTR

SGND

C1P C1N

PGND

PVSS

SVSS VDD

SHDN

1µF

O.47µF

INL

INR

µCONTROLLER

STEREO

DAC

1µF

100kΩ

VDD

1µF

VDD

MUTE

PGND GND

System Diagram

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

16 ______________________________________________________________________________________

CHARGE

PUMP

UVLO/

SHUTDOWN

CONTROL

CLICK-AND-POP

SUPPRESSION

C1N

C1P

PVSS SVSS PGND SGND

*RIN AND RF VALUES ARE CHOSEN FOR A GAIN -1.5V/V.

( ) UCSP PACKAGE

INR

VDD SHDN

OFF

SVSS

VDD

SGND

INL

RF*

30kΩ

RIN*

20kΩ

RIN*

20kΩ

OUTR

LEFT

AUDIO

INPUT

RIGHT

AUDIO

INPUT

HEADPHONE

JACK

(A2)

(B1)

(C1)

(C2)

(C3)

(C4)

(B4)

(A4)

(B3)

(A3)

(A1)

1µF

2.7V TO 5.5V

1µF

CIN

0.47µF

SVSS

VDD

OUTL

CIN

0.47µF

(B2)

RF*

30kΩ

MAX9724A

Functional Diagram/Typical Operating Circuits

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

______________________________________________________________________________________ 17

CHARGE

PUMP

UVLO/

SHUTDOWN

CONTROL

CLICK-AND-POP

SUPPRESSION

C1N

C1P

PVSS SVSS PGND SGND

( ) UCSP PACKAGE

INR

VDD SHDN

SVSS

VDD

SGND

INL

30kΩ

RIN

20kΩ

RIN*

20kΩ

OUTR

LEFT

AUDIO

INPUT

RIGHT

AUDIO

INPUT

HEADPHONE

JACK

(A2)

(B1)

(C1)

(C2)

(C3)

(C4)

(B4)

(A4)

(B3)

(A3)

(A1)

1µF

2.7V TO 5.5V

1µF

CIN

0.47µF

VSS

VDD

OUTL

CIN

0.47µF

(B2)

RF*

30kΩ

MAX9724B

OFF

Functional Diagram/Typical Operating Circuits (continued)

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

18 ______________________________________________________________________________________

TOP VIEW

987

MAX9724A

MAX9724B

TQFN

C1P

PGND

C1N

PVSS

SHDN

INL

SGND

INR

SVSS

OUTR

OUTL

VDD

Pin Configurations

UCSP

TOP VIEW (BUMPS ON BOTTOM)

MAX9724A/MAX9724B

1234

SGND SHDN OUTR OUTL

VDD INR INL SVSS

C1P PGND C1N PVSS

Chip Information

TRANSISTOR COUNT: 993

PROCESS: BiCMOS

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

______________________________________________________________________________________ 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.)

12x16L QFN THIN.EPS

0.10 C0.08 C

0.10 M C A B

D/2

E/2

E2/2

(ND - 1) X e

(NE - 1) X e

D2/2

PACKAGE OUTLINE

21-0136 2

8, 12, 16L THIN QFN, 3x3x0.8mm

MARKING

AAAA

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

20 ______________________________________________________________________________________

EXPOSED PAD VARIATIONS

CODES

PKG.

T1233-1

MIN.

0.95

NOM.

1.10

NOM.

1.10

MAX.

1.25

MIN.

0.95

MAX.

1.25

12N

0.25

0.20 REF

0.02

0.05

0.45

2.90

0.20

2.90

0.70

0.50 BSC.

0.55

3.00

0.65

3.10

0.25

3.00

0.75

0.30

3.10

0.80

0.20 REF

0.25 -

0.02

0.05

0.50 BSC.

0.30

2.90

0.40

3.00

0.20

2.90

0.70

0.25

3.00

0.75

3.10

0.50

0.80

3.10

0.30

PKG

REF. MIN.

12L 3x3

NOM. MAX. NOM.

16L 3x3

MIN. MAX.

0.35 x 45°

PIN ID JEDEC

WEED-1

T1233-31.10 1.25 0.95 1.10 0.35 x 45°1.25 WEED-1

0.95

T1633F-3 0.65

T1633-4 0.95

0.80 0.95 0.65 0.80

1.10 1.25 0.95 1.10

0.225 x 45°

0.95 WEED-2

0.35 x 45°

1.25 WEED-2

T1633-2 0.95 1.10 1.25 0.95 1.10 0.35 x 45°

1.25 WEED-2

PACKAGE OUTLINE

21-0136 2

8, 12, 16L THIN QFN, 3x3x0.8mm

WEED-11.25

1.100.95 0.35 x 45°

1.251.10

0.95

T1233-4

T1633FH-3 0.65 0.80 0.95 0.225 x 45°

0.65 0.80 0.95 WEED-2

NOTES:

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 0.20 mm AND 0.25 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 REVISION C.

10. MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY.

11. NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY.

12. WARPAGE NOT TO EXCEED 0.10mm.

0.25 0.30 0.35

0.25

0.20 REF

0.02 0.05

0.35

0.55 0.75

2.90

2.90 3.00 3.10

0.65 BSC.

3.00 3.10

8L 3x3

MIN.

0.70 0.75 0.80

NOM. MAX.

TQ833-1 1.250.25 0.70 0.35 x 45° WEEC1.250.700.25

T1633-5 0.95 1.10 1.25 0.35 x 45° WEED-20.95 1.10 1.25

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.)

MAX9724A/MAX9724B

60mW, DirectDrive, Stereo Headphone Amplifier

with Low RF Susceptibility and Shutdown

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.

Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 21

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.)

12L, UCSP 4x3.EPS

21-0104

PACKAGE OUTLINE, 4x3 UCSP

Revision History

Pages changed at Rev 2: 1, 2, 3, 6, 9, 12, 14–19

Pages changed at Rev 3: 1–6, 19

Pages changed at Rev 4: 1–6, 14–21

ENGLISH • ???? • ??? • ???

WHAT'S NEW

PRODUCTS

SOLUTIONS

DESIGN

APPNOTES

SUPPORT

BUY

COMPANY

MEMBERS

MAX9724A

Part Number Table

Notes:

See the MAX9724A QuickView Data Sheet for further information on this product family or download the

MAX9724A full data sheet (PDF, 464kB).

Other options and links for purchasing parts are listed at: http://www.maxim-ic.com/sales.2.

Didn't Find What You Need? Ask our applications engineers. Expert assistance in finding parts, usually within

one business day.

Part number suffixes: T or T&R = tape and reel; + = RoHS/lead-free; # = RoHS/lead-exempt. More: See full

data sheet or Part Naming Conventions.

* Some packages have variations, listed on the drawing. "PkgCode/Variation" tells which variation the

product uses.

Part Number

Free

Sample

Buy

Direct

Package:

TYPE PINS SIZE

DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?

Materials Analysis

MAX9724AEVKIT

RoHS/Lead-Free: No

MAX9724AEUD+T

-40C to +85C

RoHS/Lead-Free: Yes

MAX9724AETC+

THIN QFN;12 pin;3X3X0.8mm

Dwg: 21-0136I (PDF)

Use pkgcode/variation: T1233+1*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

MAX9724AETC+T

THIN QFN;12 pin;3X3X0.8mm

Dwg: 21-0136I (PDF)

Use pkgcode/variation: T1233+1*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

MAX9724AEUD+

TSSOP;14 pin;4.4mm

Dwg: 21-0066I (PDF)

Use pkgcode/variation: U14+1*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

MAX9724AEBC+

UC SP;12 pin;

Dwg: 21-0104F (PDF)

Use pkgcode/variation: B12+1*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

MAX9724AEBC+T

UC SP;12 pin;

Dwg: 21-0104F (PDF)

Use pkgcode/variation: B12+1*

-40C to +85C

RoHS/Lead-Free: Yes

Materials Analysis

Didn't Find What You Need?

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