Rainbow Electronics MAX9877 User Manual

General Description

The MAX9877 combines a high-efficiency Class D
audio power amplifier with a stereo Class AB capacitor­less DirectDrive

®

headphone amplifier. Maxim’s 3rd
generation, filterless Class D amplifier with active emis­sions limiting technology provides Class AB perfor­mance with Class D efficiency.

The MAX9877 delivers up to 725mW from a 3.7V supply
into an 8Ω load with 87% efficiency to extend battery life.
The filterless modulation scheme combined with active
emissions limiting circuitry and spread-spectrum modu­lation greatly reduces EMI while eliminating the need for
output filtering used in traditional Class D devices.

The stereo Class AB headphone amplifier in the
MAX9877 uses Maxim’s patented DirectDrive architec­ture, that produces a ground-referenced output from a
single supply, eliminating the need for large DC-blocking
capacitors, saving cost, space, and component height.

The device utilizes a user-defined input architecture,
three preamplifier gain settings, an input mixer, volume
control, comprehensive click-and-pop suppression, and
I

2

C control. A bypass mode feature disables the integrat­ed Class D amplifier and utilizes an internal DPST switch
to allow an external amplifier to drive the speaker that is
connected at the outputs of the MAX9877.

The MAX9877 is available in a thermally efficient,
space-saving 20-bump WLP package.

Applications

Cell Phones

Portable Multimedia Players

Features

♦ Low Emissions, Filterless Class D Amplifier

Achieves Better than 10dB Margin Under EN55022
Class B Limits

♦ Low RF Susceptibility Design Rejects TDMA

Noise from GSM Radios

♦ Input Mixer with User-Defined Input Mode
♦ 725mW Speaker Output (R

SPK

= 8Ω, PVDD= 3.7V)

♦ 53mW Headphone Output (R

HP

= 16Ω, VDD= 3.7V)

♦ Low 0.05% THD+N at 1kHz (Class D Power

Amplifier)

♦ Low 0.016% THD+N at 1kHz (Headphone

Amplifier)

♦ 87% Efficiency (R

SPK

= 8Ω, P

OUT

= 750mW)

♦ 1.6

Ω

Ω

Analog Switch for Speaker Amplifier Bypass

♦ High Speaker Amplifier PSRR (72dB at 217Hz)
♦ High Headphone Amplifier PSRR (84dB at 217Hz)
♦ I

2

C Control

♦ Hardware and Software Shutdown Mode
♦ Click-and-Pop Suppression
♦ Current-Limit and Thermal Protection
♦ Available in a Space-Saving, 2.5mm x 2.0mm WLP

Package

MAX9877

Low RF Susceptibility, Mono Audio

Subsystem with DirectDrive Headphone Amplifier

________________________________________________________________

Maxim Integrated Products

1

Simplified Block Diagram

WLP

HPL V

SS

C1N

HPR

1

A

B

C

D

2

3

4

C1P

BIAS SDA

RXIN+

V

DD

OUT+

INB1 SCL

PGND

INB2

PV

DD

INA1 GND

RXIN-

INA2

OUT-

5

TOP VIEW

(BUMP SIDE DOWN)

Pin Configuration

19-4076; Rev 0; 7/08

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.

EVALUATION KIT

AVAILABLE

Ordering Information

PART

PIN - PA C K A G E

MAX9877EWP+TG45

20 WLP (5x4)

+

Denotes a lead-free package.
T = Tape and reel.
G45 indicates protective die coating.

TEMP RANGE

-40°C to +85°C

PREAMPLIFIER

I2C

INTERFACE

SINGLE SUPPLY

2.7V TO 5.25V

VOLUME

CONTROL

MIXER/MUX

MAX9877

VOLUME

CONTROL

BYPASS

MAX9877

Low RF Susceptibility, Mono Audio
Subsystem with DirectDrive Headphone Amplifier

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VDD= PVDD= 3.7V, V

GND

= V

PGND

= 0V. Single-ended inputs, preamp gain = 0dB, volume controls = 0dB, OSC = 00, BYPASS = 0,

SHDN = 1. Speaker loads (Z

SPK

) connected between OUT+ and OUT-. Headphone loads (RHP) connected from HPL or HPR to GND.

SDA and SCL pullup voltage = 3.3V. Z

SPK

= ∞, RHP= ∞. C1 = C2 = C

BIAS

= 1µF. TA= T

MIN

to T

MAX

, unless otherwise noted. Typical

values are at T

A

= +25°C.) (Note 3)

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.

Note 1: HPR and HPL should be limited to no more than 9V above VSS, or above PVDD+ 0.3V, whichever limits first.
Note 2: HPR and HPL should be limited to no more than 9V below PV

DD

, or below VSS- 0.3V, whichever limits first.

V

DD

, PVDDto PGND..............................................-0.3V to +5.5V

V

DD

to PVDD..........................................................-0.3V to +0.3V

V

SS

to PGND .........................................................-5.5V to +0.3V

C1N to PGND..............................................(V

SS

- 0.3V) to +0.3V

C1P to PGND ...........................................-0.3V to (PV

DD

+ 0.3V)

HPL, HPR to V

SS

(Note 1) ......-0.3V to the lower of (PVDD- (VSS+ 0.3V)) or +9V

HPL, HPR to PV

DD

(Note 2) ......+0.3V to the higher of (VSS- (PVDD- 0.3V)) or -9V

GND to PGND.....................................................................±0.3V

INA1, INA2, INB1, INB2, BIAS..................................-0.3V to +4V

SDA, SCL...............................................................-0.3V to +5.5V

All Other Pins to GND...............................-0.3V to (PV

DD

+ 0.3V)

Continuous Current In/Out of PV

DD

, PGND, OUT_.........±800mA

Continuous Current In/Out of HPR and HPL .....................140mA

Continuous Current In/Out of RXIN+ and RXIN- ...............150mA

Continuous Input Current V

SS

...........................................100mA

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

Duration of OUT_ Short Circuit to GND or PV

DD

........Continuous

Duration of Short Circuit Between OUT+ and OUT- ..Continuous
Duration of HP_ Short Circuit to GND or PV

DD

..........Continuous

Continuous Power Dissipation (T

A

= +70°C)
20-Bump WLP, 5 x 4, Multilayer Board

(derate 13.0mW/°C above +70°C)..................................1.04W

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

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

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

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

Supply Voltage Range VDD, PVDDGuaranteed by PSRR test 2.7 5.25 V

Quiescent Current I

Shutdown Current I

Turn-On Time t

BIAS Release Time t

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

HP mode,
OUTMODE = 2

DD

SHDN

ON

BR

SPK mode,
OUTMODE = 7

SPK + HP mode,
OUTMODE = 9

I

= I

SHDN

V

Time from shutdown to
full operation

After forcing BIAS low, time from BIAS
released to I

VDD

= logic-high; TA = +25°C

SCL

+ I

2

C reset

; SHDN = 0; V

PVDD

OSC = 00 5.6 9.0

OSC = 10 5.5

OSC = 00 6.6 11.0

OSC = 10 5.7

OSC = 00 10.4 16.0

OSC = 10 9.3

OSC = 00 10

OSC = 01 10

OSC = 10 17.5

SDA

=

10 22 µA

25 80 ms

mA

ms

Input Resistance R

TA = +25°C, preamp gain = 0dB or +9dB 11 21 31

IN

TA = +25°C, preamp gain = +20dB 3 5.5 8

Preamp = 0dB 2.30

Preamp = +9dB 0.820Maximum Input Signal Swing

Preamp = +20dB 0.230

kΩ

V

P-P

MAX9877

Low RF Susceptibility, Mono Audio

Subsystem with DirectDrive Headphone Amplifier

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VDD= PVDD= 3.7V, V

GND

= V

PGND

= 0V. Single-ended inputs, preamp gain = 0dB, volume controls = 0dB, OSC = 00, BYPASS = 0,

SHDN = 1. Speaker loads (Z

SPK

) connected between OUT+ and OUT-. Headphone loads (RHP) connected from HPL or HPR to GND.

SDA and SCL pullup voltage = 3.3V. Z

SPK

= ∞, RHP= ∞. C1 = C2 = C

BIAS

= 1µF. TA= T

MIN

to T

MAX

, unless otherwise noted. Typical

values are at T

A

= +25°C.) (Note 3)

Input DC Voltage IN_ inputs 1.22 1.3 1.38 V

Bias Voltage V

SPEAKER AMPLIFIER (OUTMODE = 1)

Output Offset Voltage V

Click-and-Pop Level K

Power-Supply Rejection Ratio
(Note 4)

Output Power (Note 5) P

Total Harmonic Distortion Plus
Noise

Signal-to-Noise Ratio SNR

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

f

= 1kHz (differential

IN

input mode)

BIAS

TA = +25°C (volume at mute) ±0.5 ±4

OS T

CP

PSRR

OUT

THD+N

= +25°C (volume at 0dB,

A

OUTMODE = 1, ΔIN_ = 0)

Peak voltage, TA =
+25°C, A-weighted, 32
samples per second,
volume at mute (Note 4)

TA = +25°C, PVDD =
V

DD

THD+N ≤ 1%

f = 1kHz, P

= 8Ω + 68µH

Z

SPK

A-weighted,
OUTMODE = 1, 3,
4, 6

A-weighted,
OUTMODE = 7, 9

= 350mW, TA = +25°C,

OUT

Preamp = 0dB 47

Preamp = +9dB 49Common-Mode Rejection Ratio CMRR

Preamp = +20dB 42

Into shutdown -70

Out of shutdown -70

PVDD = VDD =

2.7V to 5.5V

f = 217Hz,
100mV

P-P

f = 1kHz,
100mV

P-P

f = 20kHz,
100mV

P-P

Z

= 8Ω +

SPK

68µH, V

Z
68µH, V

Z
68µH, V

Z
33µH, V

Z
33µH, V

ΔIN_ = 0
(single-ended)

ΔIN_ = 1 (differential) 94

ΔIN_ = 0

(single-ended)

ΔIN_ = 1 (differential) 92

SPK

SPK

SPK

SPK

DD

= 8Ω +

DD

= 8Ω +

DD

= 4Ω +

DD

= 4Ω +

DD

ripple

ripple

ripple

= 3.7V

= 3.3V

= 3.0V

= 3.7V

= 3.0V

1.13 1.2 1.27 V

50 76

±1.5

72

68

55

725

560

465

825

770

0.05 %

92

88

dB

mV

dBV

dB

mW

dB

MAX9877

Low RF Susceptibility, Mono Audio
Subsystem with DirectDrive Headphone Amplifier

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(VDD= PVDD= 3.7V, V

GND

= V

PGND

= 0V. Single-ended inputs, preamp gain = 0dB, volume controls = 0dB, OSC = 00, BYPASS = 0,

SHDN = 1. Speaker loads (Z

SPK

) connected between OUT+ and OUT-. Headphone loads (RHP) connected from HPL or HPR to GND.

SDA and SCL pullup voltage = 3.3V. Z

SPK

= ∞, RHP= ∞. C1 = C2 = C

BIAS

= 1µF. TA= T

MIN

to T

MAX

, unless otherwise noted. Typical

values are at T

A

= +25°C.) (Note 3)

Output Frequency

Current Limit 1.5 A

Efficiency η P

Speaker Gain A

Output Noise

HEADPHONE AMPLIFIERS (OUTMODE = 2)

Output Offset Voltage V

Click-and-Pop Level K

Power-Supply Rejection Ratio
(Note 4)

Output Power P

Headphone Gain A

Channel-to-Channel Gain
Tracking

Total Harmonic Distortion Plus
Noise

Signal-to-Noise Ratio SNR

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Spread-spectrum modulation mode,
OSC = 00

Fixed-frequency mode, OSC = 01 1100

Fixed-frequency mode, OSC = 10 700

= 600mW, f = 1kHz 87 %

OUT

V

A-weighted, OUTMODE = 1, ΔIN_ = 0
(Note 4)

OS

CP

PSRR

OUT

THD+N

TA = +25°C (volume at mute) ±0.15 ±0.6

TA = +25°C (volume at 0dB) ±1.6

Peak voltage, TA =
+25°C, A-weighted,
32 samples per
second. volume at
mute (Note 4)

TA = +25°C, PVDD =
V

DD

THD+N ≤ 1%

V

TA = +25°C, HPL to HPR, volume at 0dB,
OUTMODE = 2, 5; ΔIN_ = 0

RHP = 32Ω (P

R

= 16Ω (P

HP

= +25°C

T

A

A-weighted,
OUTMODE = 2, 3,
5, 6; R

A-weighted, R
16Ω, OUTMODE =
8, 9

HP

= 16Ω

OUT

OUT

HP

=

Into shutdown -80

Out of shutdown -80

PVDD = VDD = 2.7V
to 5.25V

f = 217Hz,
V

= 100mV

RIPPLE

f = 1kHz,
V

= 100mV

RIPPLE

f = 20kHz,
V

= 100mV

RIPPLE

RHP = 16Ω 53

= 32Ω 27

R

HP

= 10mW, f = 1kHz) 0.016

= 10mW, f = 1kHz),

ΔIN_ = 0
(single-ended)

ΔIN_ = 1 (differential) 98

ΔIN_ = 0

(single-ended)

ΔIN_ = 1 (differential) 96

1176

±60

11.5 12.0 12.5 dB

63 µV

70 85

P-P

P-P

P-P

-0.4 0 +0.4 dB

84

80

62

±0.3 ±2.5 %

0.03

98

96

kHz

RMS

mV

dBV

dB

mW

%

dB

MAX9877

Low RF Susceptibility, Mono Audio

Subsystem with DirectDrive Headphone Amplifier

_______________________________________________________________________________________ 5

ELECTRICAL CHARACTERISTICS (continued)

(VDD= PVDD= 3.7V, V

GND

= V

PGND

= 0V. Single-ended inputs, preamp gain = 0dB, volume controls = 0dB, OSC = 00, BYPASS = 0,

SHDN = 1. Speaker loads (Z

SPK

) connected between OUT+ and OUT-. Headphone loads (RHP) connected from HPL or HPR to GND.

SDA and SCL pullup voltage = 3.3V. Z

SPK

= ∞, RHP= ∞. C1 = C2 = C

BIAS

= 1µF. TA= T

MIN

to T

MAX

, unless otherwise noted. Typical

values are at T

A

= +25°C.) (Note 3)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Slew Rate SR 0.35 V/µs

Capacitive Drive C

Crosstalk HPL to HPR, HPR to HPL, f = 20Hz to 20kHz 65 dB

Charge-Pump Frequency

VOLUME CONTROL

Minimum Setting _VOL = 1 -75 dB

Maximum Setting _VOL = 31 0 dB

Mute Attenuation f = 1kHz, _VOL = 0

Zero-Crossing Detection Timeout ZCD = 1 60 ms

ANALOG SWITCH

On-Resistance R

Total Harmonic Distortion

Off-Isolation

DIGITAL INPUTS

Input-Voltage High (SDA, SCL) V

Input-Voltage Low (SDA, SCL) V

Input-Voltage Low (BIAS) V

Input Hysteresis (SDA, SCL) V

SDA, SCL Input Capacitance C

Input Leakage Current I

BIAS Pullup Current I

DIGITAL OUTPUTS (SDA Open Drain)

Output Low Voltage SDA V

Output Fall Time SDA t

L

Spread-spectrum modulation mode,
OSC = 00

100 pF

588

±30

Fixed-frequency mode, OSC = 01 430 550 670

Fixed-frequency mode, OSC = 10 220 350 500

PGAIN_ = 00 0

PGAIN_ = 01 9Preamp Gain Input A or B

PGAIN_ = 10 20

Speaker 100

Headphone 110

I

ON

= 20mA, RXIN_

RXIN_

= 0V and V

DD,

BYPASS = 1

V

DIF

V

CM

= 2V
= VDD/2,

P-P

,

f = 1kHz, BYPASS = 1,
T

= +25°C

A

TA = +25°C 1.6 4.5

= T

MIN

to T

MAX

T

A

Series resistance
is 9.1Ω per switch

0.05 0.25

5.2

No series resistors 0.3

BYPASS = 0, RXIN+ and RXIN- to GND =
50Ω, Z

= 8Ω + 68µH, f = 10kHz,

SPK

88 dB

referred to speaker output signal

H

BL

HYS

IN

IN

BIAS

OL

OF

L

SDA, SCL; TA = +25°C ±1.0 µA

I

= 3mA 0.4 V

SINK

V

to V

H(MIN)

to 400pF, I

bus capacitance = 10pF

L(MAX)

= 3mA

SINK

1.4 V

0.4 V

0.15 V

80 mV

4pF

94 µA

250 ns

kHz

dB

dB

Ω

%

MAX9877

Low RF Susceptibility, Mono Audio
Subsystem with DirectDrive Headphone Amplifier

6 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(VDD= PVDD= 3.7V, V

GND

= V

PGND

= 0V. Single-ended inputs, preamp gain = 0dB, volume controls = 0dB, OSC = 00, BYPASS = 0,

SHDN = 1. Speaker loads (Z

SPK

) connected between OUT+ and OUT-. Headphone loads (RHP) connected from HPL or HPR to GND.

SDA and SCL pullup voltage = 3.3V. Z

SPK

= ∞, RHP= ∞. C1 = C2 = C

BIAS

= 1µF. TA= T

MIN

to T

MAX

, unless otherwise noted. Typical

values are at T

A

= +25°C.) (Note 3)

Note 3: All devices are 100% production tested at room temperature. All temperature limits are guaranteed by design.
Note 4: Amplifier inputs are AC-coupled to GND.
Note 5: Output levels higher than 825mW are not recommended for extended durations. Production tested with Z

SPK

= 8Ω + 68µH only.

2-WIRE INTERFACE TIMING

External Pullup Voltage Range:
SDA and SCL

Serial Clock Frequency f

Bus Free Time Between STOP
and START Conditions

START Condition Hold t

START Condition Setup Time t

Clock Low Period t

Clock High Period t

Data Setup Time t

Data Hold Time t

Maximum Receive SCL/SDA Rise
Time

Maximum Receive SCL/SDA Fall
Time

Setup Time for STOP Condition t

Capacitive Load for Each Bus
Line

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

SCL

t

BUF

HD:STA

SU:STA

LOW

HIGH

SU:DAT

HD:DAT

t

R

t

F

SU:STO

C

b

1.7 3.6 V

DC 400 kHz

1.3 µs

0.6 µs

0.6 µs

1.3 µs

0.6 µs

100 ns

0 900 ns

0.6 µs

300 ns

300 ns

400 pF

MAX9877

Low RF Susceptibility, Mono Audio

Subsystem with DirectDrive Headphone Amplifier

_______________________________________________________________________________________ 7

Typical Operating Characteristics

(VDD= PVDD= 3.7V, V

GND

= V

PGND

= 0V. Single-ended inputs, preamp gain = 0dB, volume controls = 0dB, OSC = 00, BYPASS =

0, SHDN = 1. Speaker loads (Z

SPK

) connected between OUT+ and OUT-. Headphone loads (RHP) connected from HPL or HPR to

GND. Z

SPK

= ∞, RHP= ∞. C1 = C2 = C

BIAS

= 1µF. TA= +25°C, unless otherwise noted.)

GENERAL

SUPPLY CURRENT

vs. SUPPLY VOLTAGE

9

HEADPHONE ONLY
INPUTS AC-COUPLED TO GND
OUTMODE = 8

8

= V

V

7

6

SUPPLY CURRENT (mA)

5

4

2.5 5.5

= 3.3V

SDA

SCL

f

= 1176kHz SREAD-SPECTRUM MODE

OSC

f

= 700kHz

OSC

SUPPLY VOLTAGE (V)

SHUTDOWN CURRENT

vs. SUPPLY VOLTAGE

14

INPUTS AC-COUPLED TO GND

= V

SDA

SCL

= 3.3V

V

13

12

f

OSC

= 1100kHz

5.04.54.03.53.0

SUPPLY CURRENT

vs. SUPPLY VOLTAGE

10

SPEAKER ONLY
INPUTS AC-COUPLED TO GND

MAX9877 toc01

9

OUTMODE = 7

= V

= 3.3V

V

SDA

8

7

6

SUPPLY CURRENT (mA)

5

4

MAX9877 toc04

SCL

f

= 1176kHz

OSC

SPREAD-SPECTRUM MODE

f

= 1100kHz

OSC

2.5 5.5
SUPPLY VOLTAGE (V)

f

OSC

= 700kHz

5.04.54.03.53.0

MAX9877 toc02

20

0

-20

SUPPLY CURRENT

vs. SUPPLY VOLTAGE

13

HEADPHONE AND SPEAKER
INPUTS AC-COUPLED TO GND

12

OUTMODE = 9

= V

SDA

f

SCL

OSC

= 3.3V

f

OSC

SPREAD-SPECTRUM MODE

= 1100kHz

SUPPLY VOLTAGE (V)

V

11

10

9

SUPPLY CURRENT (mA)

8

7

2.5 5.5

VOLUME ATTENUATION

vs. _VOL CONTROL CODE

f

OSC

= 1176kHz

MAX9877 toc03

= 700kHz

5.04.54.03.53.0

MAX9877 toc05

11

10

9

SHUTDOWN CURRENT (μA)

8

7

2.5 5.5
SUPPLY VOLTAGE (V)

-40

-60

-80

VOLUME ATTENUATION (dB)

fIN = 1kHz

-100

MEASURED AT HPL
AND HPR

-120

5.04.54.03.53.0

35 0

_VOL CONTROL CODE

15

5

10202530

MAX9877

Low RF Susceptibility, Mono Audio
Subsystem with DirectDrive Headphone Amplifier

8 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VDD= PVDD= 3.7V, V

GND

= V

PGND

= 0V. Single-ended inputs, preamp gain = 0dB, volume controls = 0dB, OSC = 00, BYPASS =

0, SHDN = 1. Speaker loads (Z

SPK

) connected between OUT+ and OUT-. Headphone loads (RHP) connected from HPL or HPR to

GND. Z

SPK

= ∞, RHP= ∞. C1 = C2 = C

BIAS

= 1µF. TA= +25°C, unless otherwise noted.)

SPEAKER AMPLIFIER

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY

MAX9877 toc06

FREQUENCY (Hz)

THD+N (%)

10k1k100

0.1

1

10

0.01
10 100k

VDD = PVDD = 3.7V
Z

SPK

= 8Ω + 68μH

P

OUT

= 200mW

P

OUT

= 675mW

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY

MAX9877 toc07

FREQUENCY (Hz)

THD+N (%)

10k1k100

0.1

1

10

0.01
10 100k

VDD = PV

DD

= 3.7V

Z

SPK

= 4Ω + 33μH
DASHED LINES ARE LIMITED
BY THE ABS. MAX RATINGS

P

OUT

= 1100mW

P

OUT

= 650mW

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY

MAX9877 toc08

FREQUENCY (Hz)

THD+N (%)

10k1k100

0.1

1

10

0.01
10 100k

P

OUT

= 425mW

P

OUT

= 200mW

VDD = PVDD = 3V
Z

SPK

= 8Ω + 68μH

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY

MAX9877 toc09

FREQUENCY (Hz)

THD+N (%)

10k1k100

0.1

1

10

0.01
10 100k

P

OUT

= 700mW

P

OUT

= 250mW

VDD = PVDD = 3V
Z

SPK

= 4Ω + 33μH

THD+N (%)

0.01

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER

10

VDD = PVDD = 5V

= 4Ω + 33μH

Z

SPK

DASHED LINES ARE LIMITED
BY THE ABS. MAX RATINGS

1

fIN = 20Hz

0.1

0 2.51.0 3.00.5 2.0

fIN = 6kHz

fIN = 1kHz

1.5

OUTPUT POWER (W)

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. FREQUENCY

1

VDD = PVDD = 3.7V

= 200mW

P

OUT

= 8Ω + 68μH

Z

SPK

0.1

f

OSC

THD+N (%)

0.01
10 100k

MAX9877 toc12

= 1176kHz

f

= 700kHz

OSC

f

= 1100kHz

OSC

FREQUENCY (Hz)

10k1k100

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER

10

VDD = PVDD = 5V

= 8Ω + 68μH

Z

MAX9877 toc10

SPK

1

fIN = 20Hz

THD+N (%)

0.1

0.01
0 2.0

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER

10

VDD = PVDD = 3.7V

= 8Ω + 68μH

Z

SPK

1

fIN = 20Hz

THD+N (%)

0.1

fIN = 1kHz

0.01
0 1000600400 800200

OUTPUT POWER (mW)

MAX9877 toc11

fIN = 6kHz

fIN = 1kHz

1.51.00.5

OUTPUT POWER (W)

MAX9877 toc13

fIN = 6kHz

MAX9877

EFFICIENCY

vs. OUTPUT POWER

MAX9877 toc19

OUTPUT POWER (W)

EFFICIENCY (%)

1.5

100

0

50

60

10

80

30

70

20

90

40

0 3.00.5 2.01.0 2.5

VDD = PVDD = 5V
f

IN

= 1kHz
DASHED LINES ARE LIMITED
BY THE ABS. MAX RATINGS

Z

SPK

= 8Ω + 68μH

Z

SPK

= 4Ω + 33μH

EFFICIENCY

vs. OUTPUT POWER

MAX9877 toc20

OUTPUT POWER (W)

EFFICIENCY (%)

100

0

50

60

10

80

30

70

20

90

40

0 2.01.51.00.5

VDD = PVDD = 3.7V
f

IN

= 1kHz
DASHED LINES ARE LIMITED
BY THE ABS. MAX RATINGS

Z

SPK

= 8Ω + 68μH

Z

SPK

= 4Ω + 33μH

EFFICIENCY

vs. OUTPUT POWER

MAX9877 toc21

OUTPUT POWER (mW)

EFFICIENCY (%)

100

0

50

60

10

80

30

70

20

90

40

0 1000600200 800400

VDD = PVDD = 3.7V
f

IN

= 1kHz

Z

SPK

= 8Ω + 68μH

f

OSC

= 700kHz

f

OSC

= 1176kHz AND 1100kHz

Typical Operating Characteristics (continued)

(VDD= PVDD= 3.7V, V

GND

= V

PGND

= 0V. Single-ended inputs, preamp gain = 0dB, volume controls = 0dB, OSC = 00, BYPASS =

0, SHDN = 1. Speaker loads (Z

SPK

) connected between OUT+ and OUT-. Headphone loads (RHP) connected from HPL or HPR to

GND. Z

SPK

= ∞, RHP= ∞. C1 = C2 = C

BIAS

= 1µF. TA= +25°C, unless otherwise noted.)

Low RF Susceptibility, Mono Audio

Subsystem with DirectDrive Headphone Amplifier

_______________________________________________________________________________________ 9

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER

10

VDD = PVDD = 3.7V

= 4Ω + 33μH

Z

SPK

DASHED LINES ARE LIMITED
BY THE ABS. MAX RATINGS

1

THD+N (%)

0.1

0.01

fIN = 20Hz

0 1.51.00.5

fIN = 6kHz

fIN = 1kHz

OUTPUT POWER (W)

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER

1

VDD = PVDD = 3.7V

= 1kHz

f

IN

= 8Ω + 68μH

Z

SPK

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER

10

VDD = PVDD = 3V

= 8Ω + 68μH

Z

1

THD+N (%)

0.1

0.01

SPK

fIN = 20Hz

fIN = 1kHz

0 600400200

OUTPUT POWER (mW)

MAX9877 toc14

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER

1

f

= 1100kHz

MAX9877 toc17

OSC

f

OSC

= 700kHz

fIN = 6kHz

MAX9877 toc15

MAX9877 toc18

TOTAL HARMONIC DISTORTION PLUS

NOISE vs. OUTPUT POWER

10

VDD = PVDD = 3V

= 4Ω + 33μH

Z

SPK

DASHED LINES ARE LIMITED
BY THE ABS. MAX RATINGS

1

fIN = 20Hz

THD+N (%)

0.1

fIN = 1kHz

0.01
0 1.20.80.4 1.00.60.2

OUTPUT POWER (W)

MAX9877 toc16

fIN = 6kHz

0.1

THD+N (%)

0.01
0 800

f

= 1176kHz SSM

OSC

f

= 1100kHz

OSC

OUTPUT POWER (mW)

f

= 700kHz

OSC

600400200

0.1

f

THD+N (%)

0.01

= 1176kHz SSM

OSC

VDD = PVDD = 3.7V

= 6kHz

f

IN

= 8Ω + 68μH

Z

SPK

0 800

OUTPUT POWER (mW)

600400200