Rainbow Electronics MAX98302 User Manual

19-5169; Rev 0; 4/10

EVALUATION KIT

AVAILABLE

Stereo 2.4W Class D Amplifier

General Description

The MAX98302 stereo 2.4W 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 greatly reduces EMI. A filterless spread­spectrum modulation scheme eliminates the need for
output filtering found in traditional Class D devices. These
features reduce application component count.

The MAX98302 industry-leading 1.65mA at 3.7V, 2.25mA
at 5V, quiescent current extends battery life in portable
applications.

MAX98302

Features

S Industry-Leading Quiescent Current: 1.65mA at

3.7V, 2.25mA at 5V

S Spread Spectrum and Active Emissions Limiting

S Five Selectable Gains

S High -67dB PSRR at 217Hz

S 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-EP Package

The MAX98302 is available in a 14-pin TDFN-EP (3mm x
3mm x 0.75mm) package specified over the extended

-40NC to +85NC temperature range.

Applications

Notebook and Netbook
Computers

Cellular Phones

MP3 Players

Portable Audio Players

VoIP Phones

Ordering Information

PART TEMP RANGE PIN-PACKAGE

MAX98302ETD+

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

*EP = Exposed pad.

-40NC to +85NC

14 TDFN-EP*

Typical Application Circuit

+2.6V TO +5.5V

10µF

OUTL-

1µF

INL+ OUTL+

1µF

INL-

PVDD

GAIN GAIN

PVDD

CONTROL

0.1µF

1µF

INR+

1µF

INR-

PVDD

SHDN

_______________________________________________________________ Maxim Integrated Products 1

MAX98302

PGND

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 2.4W Class D Amplifier

ABSOLUTE MAXIMUM RATINGS

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

All Other Pins to PGND ..........................-0.3V to (PVDD + 0.3V)

Continuous Current into PVDD, PGND,

OUTL_, OUTR_ .......................................................... Q600mA

Continuous Input Current (all other pins) ........................ Q20mA

Duration of Short Circuit Between OUTL_,

OUTR_ to PVDD or PGND .....................................Continuous

Duration of Short Circuit Between OUTL+ to OUTL-,

OUTR+ to OUTR- ..................................................Continuous

MAX98302

Continuous Power Dissipation for Single Layer Board (T

= +70NC)

A

14-Pin TDFN (derate 18.5mW/NC above +70NC) ....1481.5mW

14-Pin TDFN B
14-Pin TDFN B

(Note 1) ............................................54NC/W

JA

(Note 1) ..............................................8NC/W

JC

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.

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.

ELECTRICAL CHARACTERISTICS

(V

= V

PVDD

AC measurement bandwidth, T

AMPLIFIER CHARACTERISTICS

Supply Voltage Range V
Undervoltage Lockout UVLO 2.5 V

Quiescent Supply Current I

Shutdown Supply Current
Turn-On Time t
Bias Voltage V

Voltage Gain A

Input Resistance R

Output Offset Voltage V

SHDN

= 5.0V, V

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

PGND

= T

MIN

to T

A

, unless otherwise noted. Typical values are at TA = +25NC.) (Notes 2, 3)

MAX

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

PVDD

DD

I

SHDN

ON

BIAS

Inferred from PSRR test 2.6 5.5 V

V

= 5.0V, TA = +25NC

PVDD

V

= 3.7V 1.65

PVDD

V

= 0V, TA = +25NC

SHDN

Connect GAIN to PGND 17.5 18 18.5

Connect GAIN to PGND through 100kI ±5%
resistor

Connect GAIN to PVDD 11.5 12 12.5

V

Connect GAIN to PVDD through 100kI ±5%
resistor

GAIN unconnected 5.5 6 6.5
AV = 18dB 14 20

= 15dB 14 20

A

V

= 12dB 14 20

A

IN

OS

V

= 9dB 19 28

A

V

= 6dB 26 40

A

V

TA = +25NC (Note 4)

Continuous Power Dissipation for Multilayer Board (TA = +70NC)

14-Pin TDFN (derate 24.4mW/NC above +70NC) ....1951.2mW

14-Pin TDFN B
14-Pin TDFN B

(Note 1) ............................................41NC/W

JA

(Note 1) ..............................................8NC/W

JC

Junction Temperature .....................................................+150NC

Operating Temperature Range .......................... -40NC to +85NC

Storage Temperature Range ............................ -65NC to +150NC

Lead Temperature (soldering, 10s) ................................+300NC

Soldering Temperature (reflow) ......................................+260NC

2.25 3.4

0.1 10

3.7 10 ms

1.3 V

14.5 15 15.5

8.5 9 9.5

±4 ±20

mA

FA

dB

kI

mV

2 ______________________________________________________________________________________

Stereo 2.4W Class D Amplifier

ELECTRICAL CHARACTERISTICS (continued)

(V

= V

PVDD

AC measurement bandwidth, T

Click and Pop K

Common-Mode Rejection Ratio CMRR f

Crosstalk

Power-Supply Rejection Ratio
(Note 4)

Output Power P

Total Harmonic Distortion Plus
Noise

Oscillator Frequency f
Spread-Spectrum Bandwidth
Efficiency
Output Noise V
Output Current Limit I
Thermal Shutdown Level 160
Thermal Shutdown Hysteresis 30

DIGITAL INPUT (SHDN GAIN)

Input Voltage High V
Input Voltage Low V
Input Leakage Current

Note 2: All devices are 100% production tested at T
Note 3: Testing performed with a resistive load in series with an inductor to simulate an actual speaker load. For R

Note 4: Amplifier inputs AC-coupled to ground.
Note 5: Mode transitions controlled by SHDN.

SHDN

= 5.0V, V

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

PGND

= T

MIN

to T

A

, unless otherwise noted. Typical values are at TA = +25NC.) (Notes 2, 3)

MAX

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

CP

PSRR

OUT

THD+N f

OSC

Peak voltage, A-weighted,
32/samples per second,
R

= 8I + 68FH

L

(Notes 4, 5)

= 1kHz, input referred 62 dB

IN

P

= 300mW,

OUT

R

= 8I + 68FH

L

= 2.6V to 5.5V, TA = +25NC

V

PVDD

V
R

= 200mV

RIPPLE

= 8I + 68FH

L

P-P

THD+N = 10%,
f

= 1kHz

IN

THD+N = 1%,
f

= 1kHz

IN

= 1kHz

IN

Into shutdown -54

Out of shutdown -54

f = 1kHz 92
f = 10kHz 80

f = 217Hz 67

,

f = 1kHz 65
f = 10kHz 58
R

= 4I + 33FH

L

R

= 8I + 68FH

L

R

= 8I + 68FH,

L

V

= 3.7V

PVDD

R

= 4I + 33FH

L

R

= 8I +68FH

L

R

= 8I + 68FH,

L

V

= 3.7V

PVDD

= 4I + 33FH,

R

L

V

= 1W

PVDD

= 8I + 68FH

R

L

P

= 0.5W

OUT

50 67

2.4

1.6

0.87

2

1.25

0.68

0.04

0.04

300 kHz

±7
83 %

2 A

L = 33FH. For R

= 8I, L = 68FH.

L

E THD+N = 1%, f = 1kHz, R

AV = 6dB, A weighted (Note 4) 50

N

LIM

INH

INL

= +25NC

T

A

= +25NC. All temperature limits are guaranteed by design.

A

= 8I + 68FH

L

1.4 V

dBV

FV

0.4 V

±1

= 4I,

L

MAX98302

dB

dB

W

W

%

kHz

RMS

NC
NC

FA

_______________________________________________________________________________________ 3

Stereo 2.4W Class D Amplifier

Typical Operating Characteristics

(V

= V

PVDD

to 22kHz AC measurement bandwidth, T

SHDN

= 5.0V, V

= 0V, AV = 12dB, RL = J, unless otherwise specified, RL connected between OUT_+ to OUT_-, 20Hz

PGND

= +25NC, unless otherwise noted.)

A

10

RL = 4I + 33µH
V

= 5.0V

PVDD

MAX98302

1

P

= 500mW

P

= 400mW

OUT

FREQUENCY (kHz)

OUT

THD+N (%)

0.1

0.01

0.01 100

THD+N vs. FREQUENCY

10

RL = 8I + 68µH
V

= 3.7V

PVDD

1

THD+N (%)

THD+N vs. FREQUENCY

0.1

0.01

0.01 100

P

= 350mW

OUT

FREQUENCY (kHz)

P

OUT

1010.1

= 100mW

1010.1

MAX98302 toc01

MAX98302 toc04

10

RL = 4I + 33µH
V

= 3.7V

PVDD

1

THD+N (%)

0.1

0.01

0.01 100

P

OUT

P

= 500mW

= 400mW

OUT

FREQUENCY (kHz)

THD+N vs. OUTPUT POWER

100

RL = 4I + 33µH
V

= 5.0V

PVDD

10

fIN = 6kHz

1

THD+N vs. FREQUENCY

THD+N (%)

fIN = 1kHz

0.1

0.01
0 3.0

OUTPUT POWER (W)

fIN = 100Hz

10

RL = 8I + 68µH
V

= 5.0V

MAX98302 toc02

THD+N (%)

1010.1

PVDD

1

P

= 800mW

OUT

0.1

P

= 600mW

0.01

0.01 100

OUT

1010.1

FREQUENCY (kHz)

MAX98302 toc03

THD+N vs. OUTPUT POWER

100

RL = 4I + 33µH
V

= 3.7V

THD+N vs. FREQUENCY

10

1

THD+N (%)

0.1

0.01
0

PVDD

MAX98302 toc06

fIN = 6kHz

fIN = 1kHz

fIN = 100Hz

1.501.251.000.750.500.25

OUTPUT POWER (W)

MAX98302 toc05

2.52.01.51.00.5

100

THD+N vs. OUTPUT POWER

RL = 8I + 68µH
V

= 5.0V

PVDD

10

1

THD+N (%)

0.1

0.01
0 2.0

fIN = 6kHz

fIN = 1kHz

OUTPUT POWER (W)

fIN = 100Hz

1.51.00.5

MAX98302 toc07

100

10

1

THD+N (%)

0.1

0.01
0

THD+N vs. OUTPUT POWER

RL = 8I + 68µH
V

= 3.7V

PVDD

fIN = 6kHz

fIN = 1kHz

OUTPUT POWER (W)

MAX98302 toc08

EFFICIENCY (%)

fIN = 100Hz

1.000.750.500.25

EFFICIENCY vs. OUTPUT POWER

100

V

= 5.0V

PVDD

90

80

70

60

RL = 4I + 33µH

50

40

30

20

10

0

0 2.50

OUTPUT POWER PER CHANNEL (W)

4 ______________________________________________________________________________________

MAX98302 toc09

RL = 8I + 68µH

2.001.500.50 1.00