MAXIM MAX98306 Technical data

19-5919; Rev 1; 8/11

EVALUATION KIT

AVAILABLE

Stereo 3.7W Class D Amplifier

General Description

The MAX98306 stereo 3.7W Class D amplifier provides
Class AB audio performance with Class D efficiency.
This device offers five selectable gain settings (6dB,
9dB, 12dB, 15dB, and 18dB) set by a single gain-select
input (GAIN).

Active emissions limiting, edge-rate, and overshoot con­trol circuitry combined with a filterless spread-spectrum
modulation scheme (SSM) provide excellent EMI perfor­mance while eliminating the need for output filtering found
in traditional Class D devices. These features reduce
application component count.

The IC's 2.0mA quiescent current with a 3.7V supply
extends battery life in portable applications.

The IC is available in a 14-pin TDFN (3mm x 3mm x

0.75mm) package specified over the extended -40NC to
+85NC temperature range.

Applications

Smartphones

Tablets

Cellular Phones

Accessory Speakers

MP3 Players

Portable Audio Players

VoIP Phones

Typical Application Circuit

Features

S Output Power 3.7W at 3I, 10% THD, 1.7W at 8I,

10% THD, with 5V Supply

S Passes EMI Limit Unfiltered with Up to 12in of

Speaker Cable

S High 83dB PSRR at 217Hz

S Spread-Spectrum Modulation and Active

Emissions Limiting

S Five Pin-Selectable Gains

S Excellent Click-and-Pop Suppression

S Thermal and Overcurrent Protection

S Low-Current Shutdown Mode

S Space-Saving, 3mm x 3mm x 0.75mm,

14-Pin TDFN

Ordering Information

PART TEMP RANGE

MAX98306ETD+

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

-40NC to +85NC

PIN-

PACKAGE

14 TDFN +AEV

TOP

MARK

MAX98306

+2.6V TO +5.5V

0.1µF

1µF

INL+ OUTL+

1µF

INL-

PVDD

GAIN GAIN

1µF

INR+

1µF

INR-

PVDD

SHDN

_______________________________________________________________ Maxim Integrated Products 1

PVDD

CONTROL

MAX98306

PGND

10µF

OUTL-

OUTR+

OUTR-

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.

Stereo 3.7W Class D Amplifier

ABSOLUTE MAXIMUM RATINGS

Voltage

PVDD to PGND ....................................................-0.3V to +6V

OUTL+, OUTR+, OUTL-, OUTR-

to PGND ...........................................-0.3V to (V

All Other Pins to PGND .......................................-0.3V to +6V

Current

Continuous Current Into/Out of PVDD, PGND,

OUTL+, OUTR+, OUTL-, OUTR- .............................. ±800mA

Continuous Input Current (all other pins) .................... ±20mA

MAX98306

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.

PVDD

+ 0.3V)

PACKAGE THERMAL CHARACTERISTICS (Note 1)

Junction-to-Ambient Thermal Resistance (qJA) ..............41°C/W

Junction-to-Case Thermal Resistance (qJA) .....................8°C/W

Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-

layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.

Duration of Short Circuit

OUTL+, OUTR+, OUTL-, OUTR- to PGND or PVDD .... Continuous

OUTL+ to OUTL- or OUTR+ to OUTR- ...................Continuous

Continuous Power Dissipation for a MultiLayer Board (TA = +70°C)

TDFN (deration 24.4mW/°C above +70°C) ...............1951.2mW

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

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

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

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

Soldering Temperature (reflow) ......................................+260°C

ELECTRICAL CHARACTERISTICS

(V

= V

PVDD

AC measurement bandwidth, TA = T

GENERAL

Supply Voltage Range V
Undervoltage Lockout UVLO 1.8 2.3 V

Quiescent Supply Current I

Shutdown Supply Current I
Turn On Time t
Bias Voltage V

Voltage Gain A

Channel-to-Channel Gain
Tracking

Input Resistance R

Common-Mode Rejection Ratio CMRR fIN = 1kHz, input referred 79 dB
Output Offset Voltage V

= 3.7V, V

SHDN

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

= 0V, AV = 12dB (GAIN = PVDD), RL = J, RL connected between OUT_+ to OUT_-, 20Hz to 22kHz

PGND

MIN

to T

PVDD

PVDD

SHDN

ON

BIAS

IN

OS

, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2)

MAX

Guaranteed by PSRR test 2.6 5.5 V

V

= 3.7V 2 2.7

PVDD

V

= 5.0V 2.6

PVDD

V

= 0, TA = +25NC < 1 10 FA

SHDN

3.2 10 ms

1.62 V
GAIN = PGND 17.5 18 18.5
GAIN = 100kI to PGND 14.5 15 15.5
GAIN = PVDD 11.5 12 12.5

V

GAIN = 100kI to PVDD 8.5 9 9.5
GAIN = unconnected 5.5 6 6.5

AV = 18dB (GAIN = PGND) 22 33
AV = 15Db (GAIN = 100kI to PGND) 31 46
AV = 12dB (GAIN = PVDD) 44 65
AV = 9dB (GAIN = 100kI to PVDD) 62 93
AV = 6dB (GAIN = unconnected) 89 131

TA = +25NC (Note 3) ±1 ±3 mV

/2 2.15 V

PVDD

0.1 %

mA

dB

kI

2 ______________________________________________________________________________________

Stereo 3.7W Class D Amplifier

ELECTRICAL CHARACTERISTICS (continued)

(V

= V

PVDD

AC measurement bandwidth, TA = T

Click-and-Pop Level K

Power-Supply Rejection Ratio PSRR

Output Power P

Total Harmonic Distortion Plus
Noise

Output Noise A-weighted (Note 3) 29 FV

SHDN

= 3.7V, V

= 0V, AV = 12dB (GAIN = PVDD), RL = J, RL connected between OUT_+ to OUT_-, 20Hz to 22kHz

PGND

MIN

to T

, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2)

MAX

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Into shutdown -79

Out of shutdown -73

V

= 2.6V to 5.5V,

PVDD

TA = +25NC

f = 217Hz, 200mV

P-P

ripple

f = 1kHz, 200mV

P-P

ripple

f = 10kHz, 200mV

P-P

ripple

Z

= 3I + 22FH,

SPK

V

= 5.0V

PVDD

Z

= 4I + 33FH,

SPK

V

= 5.0V

PVDD

Z

= 8I + 68FH,

SPK

V

= 5.0V

PVDD

Z

= 8I + 68FH,

SPK

V

= 3.7V

PVDD

Z

= 3I + 22FH,

SPK

V

= 5.0V

PVDD

Z

= 4I + 33FH,

SPK

V

= 5.0V

PVDD

Z

= 8I +68FH

SPK

V

= 5.0V

PVDD

Z

= 8I +68FH

SPK

V

= 3.7V

PVDD

Z

= 3I +22FH,

SPK

P

= 1.6W,

OUT

P

= 5.0V

VDD

Z

= 4I +33FH,

SPK

P

= 650mW,

OUT

P

= 3.7V

VDD

Z

= 4I +33FH,

SPK

P

= 1.3W,

OUT

V

= 5.0V

PVDD

Z

= 8I +68FH,

SPK

P

= 725mW,

OUT

P

= 5.0V

VDD

70 95

83

83

77

3.7

3

1.7

0.9

2.9

2.4

1.4

0.75

0.05

0.05 0.75

0.04

0.03

CP

OUT

THD+N

Peak voltage, TA = +25NC
A-weighted, 32 samples
per second (Notes 3, 4)

TA = +25NC
(Note 3)

THD+N = 10%

THD+N = 1%

fIN = 1kHz
TA = +25NC

MAX98306

dBV

dB

W

%

RMS

_______________________________________________________________________________________ 3

Stereo 3.7W Class D Amplifier

ELECTRICAL CHARACTERISTICS (continued)

(V

= V

PVDD

AC measurement bandwidth, TA = T

Signal-to-Noise Ratio SNR Z
Efficiency
Oscillator Frequency f
Spread-Spectrum Bandwidth 20 kHz

MAX98306

Current Limit TA = +25NC 3 A
Thermal-Shutdown Level +150 NC
Thermal Hysteresis 20 NC

DIGITAL INPUT (SHDN)

Input-Voltage High V
Input-Voltage Low V
Input Leakage Current TA = +25NC, SHDN = 0 ±1 FA

Note 2: This device is 100% production tested at TA = +25NC. All temperature limits are guaranteed by design.
Note 3: Amplifier inputs AC-coupled to ground.
Note 4: Specified at room temperature with an 8I resistive load in series with a 68µH inductive load.

SHDN

= 3.7V, V

= 0V, AV = 12dB (GAIN = PVDD), RL = J, RL connected between OUT_+ to OUT_-, 20Hz to 22kHz

PGND

MIN

to T

, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2)

MAX

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

E

OSC

IH

IL

= 8I +68FH, P

SPK

Z

= 8I +68FH, P

SPK

at 1% THD+N 99 dB

OUT

= 1.4W, f = 1kHz 92 %

OUT

160 320 540 kHz

1.4 V

0.4 V

Typical Operating Characteristics

(V

= V

PVDD

bandwidth, TA = +25NC, unless otherwise noted.)

100

V
Z

10

1

THD+N (%)

0.1

0.01

0.001
0 1.00

= 5.0V, V

SHDN

PGND

THD+N vs. OUTPUT POWER

= 3.7V

PVDD

= 8I + 68µH

LOAD

f = 6kHz

f = 1kHz

f = 100kHz

OUTPUT POWER (W)

= 0V, AV = 12dB, RL = J, RL connected between OUT_+ to OUT_-, 20Hz to 22kHz AC measurement

THD+N vs. OUTPUT POWER

MAX98306 toc02

100

10

THD+N (%)

0.1

0.01

0.001

100

V

= 5V

PVDD

Z

= 8I + 68µH

MAX98306 toc01

0.750.500.25

LOAD

10

1

f = 1kHz

THD+N (%)

0.1

0.01

0.001
0 2.00

f = 6kHz

f = 100kHz

OUTPUT POWER (W)

1.751.501.251.000.750.500.25

THD+N vs. OUTPUT POWER

V

= 5V

PVDD

Z

= 4I + 33µH

LOAD

1

0 3.5

f = 6kHz

f = 1kHz

OUTPUT POWER (W)

f = 100kHz

3.02.52.01.51.00.5

MAX98306 toc03

4 ______________________________________________________________________________________

Stereo 3.7W Class D Amplifier

Typical Operating Characteristics (continued)

(V

= V

PVDD

bandwidth, TA = +25NC, unless otherwise noted.)

SHDN

= 5.0V, V

= 0V, AV = 12dB, RL = J, RL connected between OUT_+ to OUT_-, 20Hz to 22kHz AC measurement

PGND

MAX98306

100

V

= 5V

PVDD

Z

= 3I + 22µH

LOAD

10

1

THD+N (%)

0.1

0.01

0.001
0 4.03.5

f = 6kHz

f = 1kHz

OUTPUT POWER (W)

f = 100kHz

THD+N vs. FREQUENCY

10

V

= 5V

PVDD

Z

= 4I + 33µH

LOAD

1

THD+N vs. OUTPUT POWER

0.1

THD+N (%)

0.01

0.001
10 100k

2W

200mW

FREQUENCY (Hz)

10

V

= 3.7V

PVDD

Z

= 8I + 68µH

MAX98306 toc04

3.02.52.01.51.00.5

LOAD

1

0.1

THD+N (%)

0.01

0.001

700mW

200mW

10 100k

FREQUENCY (Hz)

10k1k100

MAX98306 toc05

10

1

0.1

THD+N (%)

0.01

0.001

THD+N vs. FREQUENCY

THD+N vs. FREQUENCY

MAX98306 toc07

10

1

0.1

THD+N (%)

0.01

V
Z

PVDD

LOAD

= 5V

= 3I + 22µH

2.5W

500mW

MAX98306 toc08

OUTPUT POWER (W)

2.0

1.8

1.6

1.4

1.2

1.0

0.8

0.6

0.4

THD+N vs. FREQUENCY

V

= 5V

PVDD

Z

= 8I + 68µH

LOAD

1.3W

200mW

10 100k

FREQUENCY (Hz)

10k1k100

OUTPUT POWER vs. LOAD RESISTANCE

V

= 3.7V

PVDD

f = 1kHz

THD+N = 10%

THD+N = 1%

MAX98306 toc06

MAX98306 toc09

0.2

10k1k100

0.001
10 100k

FREQUENCY (Hz)

10k1k100

0

1 1000

R

LOAD

10010

(I)

OUTPUT POWER vs. LOAD RESISTANCE

4.0

3.5

3.0

2.5

2.0

1.5

OUTPUT POWER (W)

1.0

0.5

0

1 1000

THD+N = 10%

THD+N = 1%

R

(I)

LOAD

10010

_______________________________________________________________________________________ 5

V

PVDD

f = 1kHz

= 5V

MAX98306 toc10

OUTPUT POWER (W)

OUTPUT POWER vs. SUPPLY VOLTAGE

2.5
f = 1kHz
Z

= 8I + 68µH

LOAD

2.0

1.5

1.0

0.5

0

2.5 5.5

THD+N = 10%

THD+N = 1%

SUPPLY VOLTAGE (V)

OUTPUT POWER vs. SUPPLY VOLTAGE

4.0

f = 1kHz

3.5

MAX98306 toc11

3.0

2.5

2.0

1.5

OUTPUT POWER (W)

1.0

0.5

5.04.54.03.53.0

0

Z

LOAD

= 4I + 33µH

MAX98306 toc12

THD+N = 10%

THD+N = 1%

5.04.54.03.53.02.5 5.5

SUPPLY VOLTAGE (V)

Stereo 3.7W Class D Amplifier

Typical Operating Characteristics (continued)

(V

= V

PVDD

bandwidth, TA = +25NC, unless otherwise noted.)

SHDN

= 5.0V, V

= 0V, AV = 12dB, RL = J, RL connected between OUT_+ to OUT_-, 20Hz to 22kHz AC measurement

PGND

OUTPUT POWER vs. SUPPLY VOLTAGE

5.0

f = 1kHz

4.5

4.0

3.5

MAX98306

3.0

2.5

2.0

OUTPUT POWER (W)

1.5

1.0

0.5

0

Z

LOAD

= 3I + 22µH

THD+N = 10%

SUPPLY VOLTAGE (V)

EFFICIENCY vs. OUTPUT POWER

100

90

80

70

Z

= 8I + 68µH

LOAD

60

50

40

EFFICIENCY (%)

30

20

10

0

Z

LOAD

OUTPUT POWER (W)

THD+N = 1%

Z

LOAD

= 4I + 33µH

5.04.54.03.53.02.5 5.5

= 3I + 22µH

V

= 5.0V

PVDD

3.02.0 2.51.0 1.50.50 4.0

3.5

30

20

MAX98306 toc13

10

0

-10

AMPLITUDE (dB)

-20

-30

-40

4.0

3.5

MAX98306 toc16

3.0

2.5

2.0

1.5

SUPPLY CURRENT (mA)

1.0

0.5

0

GAIN vs. FREQUENCY

10 100k

FREQUENCY (Hz)

10k1k100

SUPPLY CURRENT vs. SUPPLY VOLTAGE

5.04.54.03.53.02.5 5.5

SUPPLY VOLTAGE (V)

MAX98306 toc14

MAX98306 toc17

EFFICIENCY vs. OUTPUT POWER

100

90

80

70

Z

= 8I + 68µH

LOAD

60

50

40

EFFICIENCY (%)

30

20

10

0

0 2.0

OUTPUT POWER (W)

Z

LOAD

Z

LOAD

= 4I + 33µH

CROSSTALK vs. FREQUENCY

0

-20

-40

-60

-80

CROSSTALK (dB)

-100

-120

-140
10 100k

FREQUENCY (Hz)

LEFT TO RIGHT

RIGHT TO LEFT

= 3I + 22µH

V

= 3.7V

PVDD

1.51.00.5

10k1k100

MAX98306 toc15

MAX98306 toc18

COMMON-MODE REJECTION RATIO

vs. FREQUENCY

100

V

= 3.7V

PVDD

90

80

70

60

50

CMRR (dB)

40

30

20

10

0

FREQUENCY (Hz)

100

MAX98306 toc19

PSRR (dB)

10k1k10010 100k

POWER-SUPPLY REJECTION

RATIO vs. FREQUENCY

90

80

70

60

50

40

30

V

= 200mV

RIPPLE

20

V

= 3.7V

PVDD

10

Z

= 8I + 68µH

LOAD

0

P-P

FREQUENCY (Hz)

10k1k10010 100k

MAX98306 toc20

20

WIDEBAND vs. FREQUENCY

0

-20

-40

AMPLITUDE (dBV)

-60

-80

-100

0.1 100
FREQUENCY (MHz)

6 ______________________________________________________________________________________

MAX98306 toc21

101

Stereo 3.7W Class D Amplifier

Typical Operating Characteristics (continued)

(V

= V

PVDD

bandwidth, TA = +25NC, unless otherwise noted.)

SHDN

= 5.0V, V

= 0V, AV = 12dB, RL = J, RL connected between OUT_+ to OUT_-, 20Hz to 22kHz AC measurement

PGND

MAX98306

0

IN-BAND vs. FREQUENCY

-20

-40

-60

-80

AMPLITUDE (dB)

-100

-120

-140
10 100k

FREQUENCY (Hz)

STARTUP RESPONSE

MAX98306 toc22

10k1k100

TIME (1ms/div)

MAX98306 toc23

SHDN
2V/div

OUTL

OUTR

SHUTDOWN RESPONSE

TIME (1ms/div)

MAX98306 toc24

SHDN
2V/div

OUTL

OUTR

_______________________________________________________________________________________ 7

Stereo 3.7W Class D Amplifier

Pin Configuration

TOP VIEW

OUTL+

OUTL-PGND

13 11 10

14

PVDD

PVDDINL+

12

OUTR+

OUTR-INR-

PGND

9

8

MAX98306

MAX98306

GAIN

EP

6

7

INR+

+

2 4 5

1

SHDN

3

INL-

TDFN

Pin Description

PIN NAME FUNCTION

1, 8 PGND Ground

2 SHDN

3 INL+ Noninverting Audio Left Input
4 INL- Inverting Audio Left Input
5 GAIN Gain Select
6 INR- Inverting Audio Right Input
7 INR+ Noninverting Audio Right Input
9 OUTR- Negative Right Speaker Output

10 OUTR+ Positive Right Speaker Output

11, 12 PVDD

13 OUTL+ Positive Left Speaker Output
14 OUTL- Negative Left Speaker Output
— EP Exposed Pad. Connect the exposed pad directly to ground.

Active-Low Shutdown Input. Drive SHDN to PGND to place the device into shutdown. Drive SHDN
above 1.4V for normal operation.

Power Supply. Bypass PVDD to PGND with a 0.1FF capacitor in parallel with a 10FF capacitor
placed as close as possible to the device.

8 ______________________________________________________________________________________

Stereo 3.7W Class D Amplifier

Detailed Description

The MAX98306 features low quiescent current, a low­power shutdown mode, comprehensive click-and-pop
suppression, and excellent RF immunity.

The IC offers Class AB audio performance with Class D
efficiency in a minimal board-space solution.

The Class D amplifier features spread-spectrum modula­tion, active emissions limiting, edge-rate, and overshoot
control circuitry that offers significant improvements to
switch-mode amplifier radiated emissions.

The amplifier also features click-and-pop suppression
that reduces audible transients on startup and shut­down, as well as thermal-overload and short-circuit
protection.

Class D Speaker Amplifier

The filterless Class D amplifier output stage offers much
higher efficiency than Class AB amplifiers. The high effi­ciency of a Class D amplifier is due to the pulse-width
modulated (PWM) rail-to-rail switching operation of the
output stage transistors. This ensures that any power
loss associated with the Class D output stage is mostly
due to the I2R loss of the MOSFET on-resistance and
quiescent current overhead.

EMI Filterless Output Stage

Traditional Class D amplifiers require the use of external
LC filters, or shielding, to meet EN55022B electromag­netic-interference (EMI) regulation standards. Maxim’s
active-emissions-limiting edge-rate control circuitry and
spread-spectrum modulation reduce EMI emissions,
while maintaining up to 92% efficiency.

Spread-spectrum modulation and active emissions limit­ing limit wideband spectral components, while propri­etary techniques ensure that the cycle-to-cycle varia­tion of the switching period does not degrade audio
reproduction or efficiency. The IC’s spread-spectrum
modulator randomly varies the switching frequency by
Q20kHz around the center frequency (320kHz). Above
10MHz, the wideband spectrum looks like noise for EMI
purposes (Figure 1).

Speaker Current Limit

If the output current of the speaker amplifier exceeds
the current limit (3A typ), the IC disables the outputs for
approximately 100Fs. At the end of 100Fs, the outputs
are reenabled. If the fault condition still exists, the IC
continues to disable and reenable the outputs until the
fault condition is removed.

Table 1. Gain Control Configuration

GAIN PIN MAXIMUM GAIN (dB)

Connect to PGND 18

Connect to PGND through
100kI ±5% resistor

Connect to PVDD 12

Connect to PVDD through
100kI ±5% resistor

Unconnected 6

90

80

70

60

50

40

30

20

EMISSIONS LEVEL (dBµV/m)

10

0

-10
0 1000

FREQUENCY (MHz)

Figure 1. EMI with 12in of Speaker Cable and No Output Filter

The IC offers five programmable gains selected using
the GAIN input.

The IC features a low-power shutdown mode, drawing
P 1FA (typ) of supply current. Drive SHDN low to place
the MAX98306 into shutdown. Drive SHDN above 1.4V
for normal operation.

Click-and-Pop Suppression

The IC speaker amplifier features Maxim’s comprehen­sive click-and-pop suppression. During startup, the
click-and-pop suppression circuitry reduces any audible
transient sources internal to the device. When entering
shutdown, the differential speaker outputs ramp down to
PGND quickly and simultaneously.

15

9

900800600 700200 300 400 500100

Selectable Gain

Shutdown

MAX98306

_______________________________________________________________________________________ 9

Stereo 3.7W Class D Amplifier

Applications Information

Filterless Class D Operation

Traditional Class D amplifiers require an output filter.
The filter adds cost and size and decreases THD perfor­mance. The IC’s filterless modulation scheme does not
require an output filter.

Because the switching frequency of the IC is well
beyond the bandwidth of most speakers, voice coil

MAX98306

movement due to the switching frequency is very small.
Use a speaker with a series inductance > 10FH. Typical
8I speakers exhibit series inductances in the 20FH to
100FH range.

Component Selection

Power-Supply Input (PVDD)

PVDD powers the speaker amplifier. PVDD ranges from

2.6V to 5.5V. Bypass PVDD with 0.1FF and 10FF capaci­tors to PGND. Apply additional bulk capacitance at the
device if long input traces between PVDD and the power
source are used.

Input Filtering

The input-coupling capacitor (CIN), in conjunction with
the amplifier’s internal input resistance (RIN), forms a
highpass filter that removes the DC bias from the incom­ing signal. These capacitors allow the amplifier to bias
the signal to an optimum DC level.

Assuming zero source impedance, CIN is:

=

C

IN

1

π ×

2 f R

−

3dB IN

Table 2. Capacitance Value for 20Hz
Highpass Filter

GAIN

18 33 241
15 46 173
12 65 122

9 93 86
6 131 61

RIN (kI)

Layout and Grounding

Proper layout and grounding are essential for optimum
performance. Good grounding improves audio perfor­mance and prevents switching noise from coupling into
the audio signal.

Use wide, low-resistance output traces. As the load
impedance decreases, the current drawn from the
device increases. At higher current, the resistance of the
output traces decrease the power delivered to the load.
For example, if 2W is delivered from the device output to
a 4I load through 100mI of total speaker trace, 1.904W
is delivered to the speaker. If power is delivered through
10mI of total speaker trace, 1.99W is delivered to the
speaker. Wide output, supply, and ground traces also
improve the power dissipation of the device.

The IC is inherently designed for excellent RF immunity.
For best performance, add ground fills around all signal
traces on top or bottom PCB planes.

CIN for 20Hz (nF)

where f
typical value as specified in the Electrical Characteristics
table. Use capacitors with adequately low-voltage coeffi­cients for best low-frequency THD performance. Table 2
shows calculated capacitance values based on a 20Hz
highpass filter.

10 _____________________________________________________________________________________

is the -3dB corner frequency and RIN is the

-3dB

Chip Information

PROCESS: CMOS

Stereo 3.7W Class D Amplifier

Block Diagram

2.6V TO 5.5V

0.1µF 10µF

PVDD

PVDD

SHDN 2

11, 12

UVLO/POWER

MANAGEMENT

CLICK-AND-POP

SUPPRESSION

LOW-EMI

DRIVER

PVDD

OUTL+

13

MAX98306

PVDD

INL+ 3

INL- 4

GAIN

INR+ 7

INR-

5

6

GAIN

CONTROL

1ST INTEGRATOR 2ND INTEGRATOR

GAIN SELECTION

1ST INTEGRATOR 2ND INTEGRATOR

GAIN SELECTION

MODULATOR

(FIXED GAIN 2x)

MODULATOR

(FIXED GAIN 2x)

LOW-EMI

DRIVER

MAX98306

LOW-EMI

DRIVER

PGND

PGND

PGND

PVDD

PVDD

PVDD

OUTL-

14

OUTR+

10

OUTR-

LOW-EMI

DRIVER

PGND

1, 8

PGND

9

______________________________________________________________________________________ 11

Stereo 3.7W Class D Amplifier

Package Information

For the latest package outline information and land patterns (footprints), go to www.maxim-ic.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.

14 TDFN T1433+2

MAX98306

LAND

PATTERN NO.

21-0137 90-0063

12 _____________________________________________________________________________________

Stereo 3.7W Class D Amplifier

Package Information (continued)

For the latest package outline information and land patterns (footprints), go to www.maxim-ic.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.

MAX98306

COMMON DIMENSIONS

SYMBOL

MIN. MAX.

A 0.70 0.80

D 2.90 3.10

E 2.90 3.10

A1

0.00 0.05

L 0.20 0.40

0.25 MIN.k

A2 0.20 REF.

PACKAGE VARIATIONS

PKG. CODE

T633-2

T833-2

T833-3

T1033-1

T1033MK-1

T1033-2

T1433-1

N D2

6 1.50±0.10 2.30±0.10 0.95 BSC MO229 / WEEA 0.40±0.05 1.90 REF

8 1.50±0.10 2.30±0.10

8 1.50±0.10 2.30±0.10

1.50±0.10

1.70±0.10 2.30±0.1014

E2 e

2.30±0.1010

2.30±0.101.50±0.10

2.30±0.10 MO229 / WEED-3 2.00 REF0.25±0.050.50 BSC1.50±0.1010

JEDEC SPEC

0.65 BSC MO229 / WEEC

0.65 BSC MO229 / WEEC

0.50 BSC

0.50 BSC MO229 / WEED-3

0.40 BSC

0.40 BSC

0.40 BSC

MO229 / WEED-3

- - - -

- - - - 0.20±0.05 2.40 REFT1433-3F 14 2.30±0.101.70±0.10

b

[(N/2)-1] x e

0.30±0.05 1.95 REF

0.30±0.05 1.95 REF

2.00 REF0.25±0.05

0.25±0.05 2.00 REF10

2.40 REF0.20±0.05- - - -

0.20±0.05 2.40 REFT1433-2 14 2.30±0.101.70±0.10

______________________________________________________________________________________ 13

Stereo 3.7W Class D Amplifier

Revision History

REVISION

NUMBER

0 6/11 Initial release —
1 8/11 Updated output power in Electrical Characteristics 3

REVISION

DATE

MAX98306

DESCRIPTION

PAGES

CHANGED

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.

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©

2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.