MAX9879

Stereo Class D Audio Subsystem

with DirectDrive Headphone Amplifier

3

Maxim Integrated

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Preamp = 0

58

Preamp = 5.5dB

55

Common-Mode Rejection Ratio

CMRR

fIN = 1kHz (differential

input mode)

Preamp = 20dB

43

dB

Input DC Voltage

IN__ inputs

1.22

1.3

1.38

V

Bias Voltage

VBIAS

1.13

1.2

1.272

V

SPEAKER AMPLIFIER

TA = +25°C (volume at mute)

±0.5

±4

mV

Output Offset Voltage

VOS

TA = +25°C (volume at 0dB, ENA = 1 and

ENB = 0 or ENB = 1 and ENA = 0,

ΔIN_ = 0)

±4.5

mV

Into shutdown

-70

Click-and-Pop Level

KCP

Peak voltage,

TA = +25°C

A-weighted, 32 samples

per second, volume at

mute (Note 5)

Out of shutdown

-70

dBV

PVDD_ = VDD

= 2.7V to 5.5V

50

76

f = 217Hz,

100mVP-P ripple

72

f = 1kHz,

100mVP-P ripple

68

Power-Supply Rejection Ratio

(Note 5)

PSRR

TA = +25°C

f = 20kHz,

100mVP-P ripple

55

dB

VDD = 3.7V

715

VDD = 3.3V

565

Output Power

POUT

THD+N

≤ 1%, RSPK =

8

Ω

VDD = 3.0V

470

mW

Total Harmonic Distortion + Noise

THD+N

f = 1kHz, POUT = 350mW, TA = +25°C,

RSPK = 8

Ω

0.04

0.2

%

ΔIN_ = 0

(single-ended)

92

A-weighted, ENA = 1

and ENB = 0 or ENB = 1

and ENA = 0

ΔIN_ = 1

(differential)

94

ΔIN_ = 0

(single-ended)

88

Signal-to-Noise Ratio

SNR

A-weighted ENA =

ENB = 1

ΔIN_ = 1

(differential)

92

dB

Output Frequency

700

±40

kHz

ELECTRICAL CHARACTERISTICS (continued)

(VDD = VPVDDL = VPVDDR = 3.7V, VCCIO = 1.8V, VGND = VPGNDL = VPGNDR = 0. Single-ended inputs, preamp = 0, volume controls =

0dB, BYPASS = 0, SHDN = 1. Speaker loads connected between OUT_+ and OUT_-. Headphone loads connected from HPL or HPR to

GND. RSPK = ∞, RHP = ∞. C1 = C2 = CBIAS = 1µF. TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.)

(Notes 3, 4)