Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsLinear ICsLinear IC - Audio amplifier 1-channel (mono) Class D TQFN 32 EP (5x5)

General Description

The MAX9703/MAX9704 mono/stereo Class D audio

power amplifiers provide Class AB amplifier performance

with Class D efficiency, conserving board space and

eliminating the need for a bulky heatsink. Using a Class

D architecture, these devices deliver up to 15W while

offering up to 78% efficiency. Proprietary and protected

modulation and switching schemes render the traditional

Class D output filter unnecessary.

The MAX9703/MAX9704 offer two modulation schemes:

a fixed-frequency mode (FFM), and a spread-spectrum

mode (SSM) that reduces EMI-radiated emissions due

to the modulation frequency. The device utilizes a fully

differential architecture, a full bridged output, and compre-

hensive click-and-pop suppression.

The MAX9703/MAX9704 feature high 80dB PSRR, low

0.07% THD+N, and SNR in excess of 95dB. Short-circuit

and thermal-overload protection prevent the devices from

being damaged during a fault condition. The MAX9703 is

available in a 32-pin TQFN (5mm x 5mm x 0.8mm) pack-

age. The MAX9704 is available in a 32-pin TQFN (7mm x

7mm x 0.8mm) package. Both devices are specified over

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

Applications

Features

● Filterless Class D Amplifier

● Unique Spread-Spectrum Mode Offers 5dB

Emissions Improvement Over Conventional Methods

● Up to 78% Efficient (R

= 8Ω)

● Up to 88% Efficient (R

= 16Ω)

● 15W Continuous Output Power into 8Ω (MAX9703)

● 2x10W Continuous Output Power into 8Ω (MAX9704)

● Low 0.07% THD+N

● High PSRR (80dB at 1kHz)

● 10V to 25V Single-Supply Operation

● Differential Inputs Minimize Common-Mode Noise

● Pin-Selectable Gain Reduces Component Count

● Industry-Leading Click-and-Pop Suppression

● Low Quiescent Current (24mA)

● Low-Power Shutdown Mode (0.2μA)

● Short-Circuit and Thermal-Overload Protection

● Available in Thermally Efficient, Space-Saving

Packages

• 32-Pin TQFN (5mm x 5mm x 0.8mm)–MAX9703

• 32-Pin TQFN (7mm x 7mm x 0.8mm)–MAX9704

Pin Configurations appears at end of data sheet.

19-3160; Rev 8; 5/14

● LCD TVs

● LCD Monitors

● Desktop PCs

● LCD Projectors

● Hands-Free Car Phone

Adapters

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

temperature range.

*EP = Exposed paddle.

+Denotes lead-free package.

PART PIN-PACKAGE AMP PKG CODE

MAX9703ETJ+ 32 TQFN-EP* Mono T3255-4

MAX9704ETJ+ 32 TQFN-EP* Stereo T3277-2

0.47µF

INL+ OUTL+

OUTL-INL-

0.47µF

H-BRIDGE

0.47µF

INR+ OUTR+

OUTR-INR-

0.47µF

H-BRIDGE

0.47µF

IN+ OUT+

OUT-

IN-

0.47µF

H-BRIDGE

MAX9704

MAX9703

MAX9703/MAX9704 10W Stereo/15W Mono, Filterless,

Spread-Spectrum, Class D Amplifiers

Block Diagrams

Ordering Information

Summary of content (24 pages)

PAGE 1
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers General Description The MAX9703/MAX9704 mono/stereo Class D audio power amplifiers provide Class AB amplifier performance with Class D efficiency, conserving board space and eliminating the need for a bulky heatsink. Using a Class D architecture, these devices deliver up to 15W while offering up to 78% efficiency.
PAGE 2
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Absolute Maximum Ratings (All voltages referenced to PGND.) VDD to PGND, AGND............................................................30V OUTR_, OUTL_, C1N.................................-0.3V to (VDD + 0.3V) C1P............................................(VDD - 0.3V) to (CHOLD + 0.3V) CHOLD........................................................(VDD - 0.3V) to +40V All Other Pins to PGND..............................
PAGE 3
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Electrical Characteristics (continued) (VDD = 15V, AGND = PGND = 0V, SHDN ≥ VIH, AV = 16dB, CSS = CIN = 0.47μF, CREG = 0.01μF, C1 = 100nF, C2 = 1μF, FS1 = FS2 = PGND (fS = 660kHz), RL connected between OUTL+ and OUTL- and OUTR+ and OUTR-, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.
PAGE 4
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Typical Operating Characteristics (33μH with 4Ω, 68μH with 8Ω, part in SSM mode, 136μH with 16Ω, measurement BW = 22Hz to 22kHz, unless otherwise noted.) POUT = 4W 0.1 1 POUT = 8W POUT = 8W 0.1 100 1k POUT = 500mW POUT = 500mW 10k 0.01 100k 10 100 1k 10k 0.01 100k 10 100 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT POWER TOTAL HARMONIC DISTORTION PLUS NOISE vs.
PAGE 5
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Typical Operating Characteristics (continued) (33μH with 4Ω, 68μH with 8Ω, part in SSM mode, 136μH with 16Ω, measurement BW = 22Hz to 22kHz, unless otherwise noted.
PAGE 6
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Typical Operating Characteristics (continued) (33μH with 4Ω, 68μH with 8Ω, part in SSM mode, 136μH with 16Ω, measurement BW = 22Hz to 22kHz, unless otherwise noted.) -60 -80 -100 -40 -60 -80 2 4 -120 6 8 10 12 14 16 18 20 FREQUENCY (kHz) TURN-ON/TURN-OFF RESPONSE MAX9703/04 toc22 100k 35 CSS = 180pF 1M 10M 1V/div OUTPUT SUPPLY CURRENT (mA) 5V/div 20ms/div 1M 10M 100M SUPPLY CURRENT vs.
PAGE 7
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Pin Description PIN NAME FUNCTION MAX9703 MAX9704 1, 2, 23, 24 1, 2, 23, 24 3, 4, 21, 22 3, 4, 21, 22 VDD Power-Supply Input 5 5 C1N Charge-Pump Flying Capacitor Negative Terminal 6 6 C1P Charge-Pump Flying Capacitor Positive Terminal PGND Power Ground 7 7 CHOLD 8, 17, 20, 25, 26, 31, 32 Charge-Pump Hold Capacitor. Connect a 1µF capacitor from CHOLD to VDD. 8 N.C. No Connection.
PAGE 8
MAX9703/MAX9704 Detailed Description The MAX9703/MAX9704 filterless, Class D audio power amplifiers feature several improvements to switchmode amplifier technology. The MAX9703 is a mono amplifier, the MAX9704 is a stereo amplifier. These devices offer Class AB performance with Class D efficiency, while occupying minimal board space. A unique filterless modulation scheme and spread-spectrum switching mode create a compact, flexible, lownoise, efficient audio power amplifier.
PAGE 9
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers VDD CIN L1* 1000pF CIN CIN L2* 1000pF MAX9704 L3* 1000pF CIN L4* 1000pF *L1–L4 = 0.05Ω DCR, 70Ω AT 100MHz, 3A FAIR RITE FERRITE BEAD (2512067007Y3). 40 AMPLITUDE (dBuV/m) 35 CE LIMIT 30 25 20 15 MAX9704 OUTPUT SPECTRUM 10 5 30 100 200 300 400 500 600 700 800 900 1000 FREQUENCY (MHz) Figure 1. MAX9704 EMI Spectrum, 9in PC Board trace, 3in Twisted-Pair Speaker Cable www.maximintegrated.
PAGE 10
MAX9703/MAX9704 EFFICIENCY vs. OUTPUT POWER 100 90 SS GPIO MUTE SIGNAL MAX9704 80 EFFICIENCY (%) 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers 0.18µF MAX9703/ MAX9704 70 60 50 Figure 3. MAX9703/MAX9704 Mute Circuit CLASS AB 40 30 20 VDD = 15V f = 1kHz RL = 8Ω 10 0 0 2 4 6 8 10 12 14 16 18 20 OUTPUT POWER (W) Figure 2. MAX9704 Efficiency vs.
PAGE 11
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Gain Selection The MAX9703/MAX9704 feature an internally set, logicselectable gain. The G1 and G2 logic inputs set the gain of the MAX9703/MAX9704 speaker amplifier (Table 2). SINGLE-ENDED AUDIO INPUT Table 2. Gain Selection IN+ MAX9703/ MAX9704 IN- G1 G2 GAIN (dB) 0 0 29.6 0 1 19.1 1 0 13 1 1 16 0.47µF Figure 4. Single-Ended Input the signal to an optimum DC level.
PAGE 12
MAX9703/MAX9704 design is failing radiated emissions due to board layout or cable length, or the circuit is near EMIsensitive devices. Use a ferrite bead filter when radiated frequencies above 10MHz are of concern. Use an LC filter when radiated frequencies below 10MHz are of concern, or when long leads connect the amplifier to the speaker. Refer to the MAX9704 Evaluation Kit schematic for details of this filter.
PAGE 13
MAX9703/MAX9704 Additional improvements are possible if all the traces from the device are made as wide as possible. Although the IC pins are not the primary thermal path of the package, they do provide a small amount. The total improvement would not exceed about 10%, but it could make the difference between acceptable performance and thermal problems.
PAGE 14
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Functional Diagrams 10V TO 25V 100µF* 25V† 0.1µF 25V† 1 2 PGND 0.47µF 0.47µF 0.18µF 10V 11 IN18 FS1 19 FS2 VREG 14 SHDN 15 G1 VREG 0.01µF 10V 3 4 VDD 21 22 23 24 VDD PGND 12 IN+ VREG VREG VREG 0.1µF 25V† 16 G2 13 SS 9 REG OUT+ 30 MODULATOR OUT- 27 OSCILLATOR MAX9703 GAIN CONTROL SHUTDOWN CONTROL C1P 6 CHARGE PUMP 5 C1N 10 AGND LOGIC INPUTS SHOWN FOR AV = 16dB (SSM). VIN = LOGIC HIGH > 2.5V.
PAGE 15
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Functional Diagrams (continued) 10V TO 25V 100µF* 25V† 0.1µF 25V† 1 2 PGND 0.47µF 0.47µF VREG VREG 0.47µF 0.47µF VREG VREG 0.18µF 10V VREG 0.01µF 10V 0.
PAGE 16
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers System Diagram VDD 100µF* 1µF 0.47µF OUTL- VDD SHDN INL- OUTL- INL+ OUTL+ 0.47µF OUTL+ CODEC MAX9704 0.47µF OUTR+ INR+ OUTR+ INR- OUTR- 0.47µF OUTR- 5V SS 100kΩ 0.18µF SHDN 1µF VDD INL1µF 15kΩ 1µF 15kΩ MAX9722B INL+ OUTL INR+ OUTR INR- PVSS SVSS 1µF 30kΩ 30kΩ C1P CIN 1µF 1µF LOGIC INPUTS SHOWN FOR AV = 16dB (SSM). *BULK CAPACITANCE, IF NEEDED. www.maximintegrated.
PAGE 17
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Pin Configurations PGND VDD VDD N.C. FS2 FS1 N.C. PGND PGND VDD VDD FS2 FS1 G2 24 23 22 21 20 19 18 17 24 23 22 21 20 19 18 17 N.C. 25 16 G2 G1 PGND TOP VIEW OUTR- 25 16 INR+ N.C. 26 15 G1 OUTR- 26 15 INR- OUT- 27 14 SHDN OUTR+ 27 14 REG. 13 AGND OUT- 28 13 SS OUTR+ 28 OUT+ 29 12 IN+ OUTL- 29 12 SS OUT+ 30 11 IN- OUTL- 30 11 SHDN N.C.
PAGE 18
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO.
PAGE 19
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. www.maximintegrated.
PAGE 20
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. www.maximintegrated.
PAGE 21
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. www.maximintegrated.
PAGE 22
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. www.maximintegrated.
PAGE 23
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. www.maximintegrated.
PAGE 24
MAX9703/MAX9704 10W Stereo/15W Mono, Filterless, Spread-Spectrum, Class D Amplifiers Revision History REVISION NUMBER REVISION DATE 8 5/14 PAGES CHANGED DESCRIPTION Removed automotive reference in Applications section and corrected package code 1 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.