19-0606; Rev 3; 9/09
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
General Description
The MAX9789/MAX9790 combine a stereo, 2W Class AB
speaker power amplifier with a stereo 100mW
DirectDrive
®
headphone amplifier in a single device. The
MAX9789/MAX9790 are designed for use with the
Microsoft Windows Vista
®
operating system and are fully
compliant with Microsoft’s Windows Vista specifications.
The headphone amplifier features Maxim’s patented
†
DirectDrive architecture that produces a ground-refer-
enced output from a single supply to eliminate the need
for large DC-blocking capacitors, as well as save cost,
board space, and component height. A high +90dB
PSRR and low 0.002% THD+N ensures clean, low-distor-
tion amplification of the audio signal.
Separate speaker and headphone amplifier control
inputs provide independent shutdown of the speaker
and headphone amplifiers, allowing speaker and head-
phone amplifiers to be active simultaneously, if
required. The industry-leading click-and-pop suppres-
sion circuitry reduces audible transients during startup
and shutdown cycles.
The MAX9789 features an internal LDO that can be used
as a clean power supply for a CODEC or other circuits.
The LDO output voltage is set internally at 4.75V or can
be adjusted between 1.21V and 4.75V using a simple
resistive divider. The LDO is protected against thermal
overloads and short circuits while providing 120mA of
continuous output current and can be enabled indepen-
dently of the audio amplifiers.
By disabling the speaker and headphone amplifiers, and
the LDO (for MAX9789), the MAX9789/MAX9790 enter
low-power shutdown mode and draw only 0.3µA.
The MAX9789/MAX9790 operate from a single 4.5V to
5.5V supply and feature thermal-overload and output
short-circuit protection. Devices are specified over the
-40°C to +85°C extended temperature range.
Features
o
Microsoft Windows Vista Compliant
o
Class AB 2W Stereo BTL Speaker Amplifier
o
100mW DirectDrive Headphone Amplifier
Eliminates Costly, Bulky DC-Blocking Capacitors
o
Excellent RF Immunity
o
Integrated 120mA LDO (MAX9789)
o
High +90dB PSRR, Low 0.002% THD+N
o
Low-Power Shutdown Mode
o
Click-and-Pop Suppression
o
Short-Circuit and Thermal-Overload Protection
o
Available in 32-Pin Thin QFN (5mm x 5mm x
0.8mm) Package
MAX9789/MAX9790
Ordering Information
PART
MAX9789AETJ+
MAX9789CETJ+
MAX9790AETJ+
PIN-PACKAGE INTERNAL LDO t
ON
(ms)
32 TQFN-EP*
Yes
100
Yes
Yes
No
25
100
100
32 TQFN-EP*
32 TQFN-EP*
MAX9789BETJ+** 32 TQFN-EP*
MAX9790BETJ+** 32 TQFN-EP*
No
25
Note:
All devices are specified over the -40°C to +85°C extended
temperature range.
+Denotes
a lead-free/RoHS-compliant package.
*EP
= Exposed pad.
**Future
product—contact factory for availability.
Simplified Block Diagrams
SPEAKER SUPPLY
4.5V TO 5.5V
HEADPHONE SUPPLY
3.0V TO 5.5V
SPKR_INR
Applications
Notebook Computers
Tablet PCs
Portable Multimedia Players
Pin Configurations appear at end of data sheet.
†
U.S. Patent # 7,061,327.
MAX9789
SPKR_INL
HP_INR
HP_INL
SPKR_EN
HP_EN
MUTE
GAIN1
GAIN2
4.5V TO 5.5V
LDO
1.21V TO 4.75V
Windows Vista is a registered trademark of Microsoft Corp.
DirectDrive is a registered trademark of Maxim Integrated
Products, Inc.
Simplified Block Diagrams continued at end of data sheet.
1
________________________________________________________________
Maxim Integrated Products
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.
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
MAX9789/MAX9790
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (V
DD
, PV
DD
, HPV
DD
,
CPV
DD
to GND) ..................................................-0.3V to +6.0V
GND to PGND, CPGND ......................................................±0.3V
CPV
SS
, C1N, V
SS
to GND......................................-6.0V to +0.3V
HPR, HPL to GND ...............................................................±3.0V
Any Other Pin .............................................-0.3V to (V
DD
+ 0.3V)
Duration of OUT_+, OUT_- Short Circuit
to GND or PV
DD
......................................................Continuous
Duration of Short Circuit between OUT_+, OUT_-
and LDO_OUT.........................................................Continuous
Duration of Short Circuit between HPR, HPL and GND,
V
SS
or HPV
DD
..........................................................Continuous
Continuous Current (PV
DD
, OUT_+, OUT_-, PGND).............1.7A
Continuous Current (CPV
DD
, C1N, C1P, CPV
SS
, PV
SS
,
V
DD,
HPV
DD
, LDO_OUT, HPR, HPL) .............................850mA
Continuous Input Current (all other pins) .........................±20mA
Continuous Power Dissipation (T
A
= +70°C)
32-Pin Thin QFN Single-Layer Board
(derate 18.6mW/°C above +70°C) ..............................1489mW
θ
JA
...........................................................................53.7°C/W
θ
JC
...........................................................................19.9°C/W
32-Pin Thin QFN Multilayer Board
(derate 24.9 mW/°C above +70°C) .............................1990mW
θ
JA
...........................................................................40.2°C/W
θ
JC
...........................................................................19.9°C/W
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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
DD
= PV
DD
= CPV
DD
= HPV
DD
= HP_EN = V
LDO_EN
(MAX9789 only) = +5V, V
GND
= V
PGND
= V
CPGND
=
SPKR_EN
= V
LDO_SET
(MAX9789 only) = 0V, I
LDO_OUT
(MAX9789 only) = 0, C1 = C2 = C
BIAS
= 1µF. R
L
=
∞,
unless otherwise specified, V
GAIN1
= 0,
V
GAIN2
= 5V (A
VSP
= 10dB, A
VHP
= 3.5dB), T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 2)
PARAMETER
GENERAL
Supply Voltage
Headphone Supply Voltage
V
DD
, PV
DD
CPV
DD
,
HPV
DD
Guaranteed by PSRR and LDO Line
Regulation Tests
Guaranteed by PSRR Test
SPKR_EN
1 (MAX9789)
Quiescent Current
I
DD
1 (MAX9790)
1
0
0
Shutdown Current
Bias Voltage
Shutdown to Full Operation
Gain Switching Time
Channel-to-Channel Gain
Tracking
SPEAKER AMPLIFIER
Output Power
Total Harmonic Distortion Plus
Noise
P
OUT
THD+N
THD+N = 1%, f = 1kHz,
T
A
= +25°C
R
L
= 8Ω, P
OUT
= 1W, f = 1kHz
R
L
= 4Ω, P
OUT
= 1W, f = 1kHz
R
L
= 4Ω
R
L
= 8Ω
2
1
0.002
0.004
W
%
I
SHDN
V
BIAS
t
SON
t
SW
MAX9789A/MAX9789C/MAX9790A
MAX9789B/MAX9790B
HP_EN
0 (MAX9789)
0 (MAX9790)
1
0
1
1.7
0.1
0.3
7
14
18
0.3
1.8
100
25
10
±0.1
0.4
6
13
29
40
6
1.9
µA
V
ms
µs
dB
mA
mA
µA
4.5
3.0
5.5
5.5
V
V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
SPKR_EN
= V
DD
, HP_EN = LDO_EN = GND
2
_______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
ELECTRICAL CHARACTERISTICS (continued)
(V
DD
= PV
DD
= CPV
DD
= HPV
DD
= HP_EN = V
LDO_EN
(MAX9789 only) = +5V, V
GND
= V
PGND
= V
CPGND
=
SPKR_EN
= V
LDO_SET
(MAX9789 only) = 0V, I
LDO_OUT
(MAX9789 only) = 0, C1 = C2 = C
BIAS
= 1µF. R
L
=
∞,
unless otherwise specified, V
GAIN1
= 0,
V
GAIN2
= 5V (A
VSP
= 10dB, A
VHP
= 3.5dB), T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 2)
PARAMETER
Power-Supply Rejection Ratio
SYMBOL
PSRR
CONDITIONS
V
DD
= 4.5V to 5.5V, T
A
= +25°C
f = 1kHz, 200mV
P-P
(Note 4)
f = 10kHz, 200mV
P-P
(Note 4)
GAIN1
0
Voltage Gain
A
V
0
1
1
GAIN1
Input Impedance
R
IN
0
0
1
1
Output Offset Voltage
V
OS
Measured between
OUT_+ and OUT_-,
T
A
= +25°C
GAIN2
0
1
0
1
GAIN2
0
1
0
1
80
65
45
25
±1
MAX9789C
±1
-50
dBV
-50
102
99
30
200
-70
1.4
THD+N = 1%, f =
1kHz, T
A
= +25°C
R
L
= 16Ω
R
L
= 32Ω
100
55
-77
0.02
0.03
-94
dB FS
dB
µV
RMS
pF
dB
V/µs
±15
mV
±25
kΩ
6
10
15.6
21.6
dB
MIN
72
TYP
90
70
50
dB
MAX
UNITS
MAX9789/MAX9790
Measured at speaker amplifier inputs
Click-and-Pop Level
K
CP
R
L
= 8Ω, peak voltage, Into shutdown
A-weighted, 32 samples
per second (Notes 3, 4) Out of shutdown
R
L
= 8Ω, P
OUT
= 1W
BW = 22Hz to 22kHz
No sustained oscillations
L to R, R to L, R
L
= 8Ω, FS = 0.707V
RMS
,
V
OUT
= 70.7nV
RMS
, 20kHz AES17,
BW = 20Hz to 20kHz
A-weighted
f = 22Hz to 22kHz
Signal-to-Noise Ratio
Noise
Capacitive-Load Drive
Crosstalk
Slew Rate
HEADPHONE AMPLIFIER
Output Power
SNR
V
n
C
L
SR
P
OUT
mW
R
L
= 32Ω, FS = 0.300V
RMS
,
V
OUT
= 210mV
RMS
, 20kHz AES17,
BW = 20Hz to 20kHz
Total Harmonic Distortion Plus
Noise
THD+N
R
L
= 32Ω, P
OUT
= 40mW, f = 1kHz
R
L
= 16Ω, P
OUT
= 60mW, f = 1kHz
R
L
= 10kΩ, FS = 0.707V
RMS
,
V
OUT
= 500mV
RMS
, 20kHz AES17,
BW = 20Hz to 20kHz
dB FS
%
_______________________________________________________________________________________
3
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
MAX9789/MAX9790
ELECTRICAL CHARACTERISTICS (continued)
(V
DD
= PV
DD
= CPV
DD
= HPV
DD
= HP_EN = V
LDO_EN
(MAX9789 only) = +5V, V
GND
= V
PGND
= V
CPGND
=
SPKR_EN
= V
LDO_SET
(MAX9789 only) = 0V, I
LDO_OUT
(MAX9789 only) = 0, C1 = C2 = C
BIAS
= 1µF. R
L
=
∞,
unless otherwise specified, V
GAIN1
= 0,
V
GAIN2
= 5V (A
VSP
= 10dB, A
VHP
= 3.5dB), T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 2)
PARAMETER
Power-Supply Rejection Ratio
Voltage Gain
Input Impedance
Output Offset Voltage
SYMBOL
PSRR
A
V
R
IN
V
OS
K
CP
Measured at headphone amplifier inputs
MAX9789C
R
L
= 32Ω, peak voltage, Into shutdown
A-weighted, 32 samples
per second (Notes 3, 4) Out of shutdown
R
L
= 32Ω, f = 1kHz, A-weighted,
FS = 0.300V
RMS
, V
OUT
= 300µV
RMS
R
L
= 10kΩ, f = 1kHz, A-weighted,
FS = 0.707V
RMS
, V
OUT
= 707µV
RMS
R
L
= 32Ω,
P
OUT
= 60mW
BW = 22Hz to 22kHz
No sustained oscillations
R
L
= 32Ω,
FS = 0.300V
RMS
,
V
OUT
= 30mV
RMS
R
L
= 10kΩ,
FS = 0.707V
RMS
,
V
OUT
= 70.7mV
RMS
500
Charge-Pump Frequency
f
OSC
MAX9789C
Inferred from line regulation
I
OUT
= 0mA
I
OUT
= 120mA
V
OUT
= 4.75V, I
OUT
= 0mA, f = 1kHz,
speaker P
OUT
= 2W, speaker R
L
= 4Ω
I
OUT
= 1mA
MAX9789C
1.21
1.18
1.18
1.21
1.21
200
475
4.5
0.1
-40
120
-95
±1.5
±3.0
4.75
1.23
1.25
LOW-DROPOUT LINEAR REGULATOR
Regulator Input Voltage Range
Ground Current
Output Current
Crosstalk
Fixed Output Voltage Accuracy
Adjustable Output Voltage Range
LDO_SET Reference Voltage
LDO_SET Dual-Mode Threshold
V
SET
MAX9789C
V
DD
I
GND
I
OUT
5.5
0.4
V
mA
mA
dB
%
V
V
mV
22Hz to 22kHz
A-weighted
T
A
= +25°C
20
CONDITIONS
HPV
DD
= 3V to 5.5V, T
A
= +25°C
f = 1kHz, V
RIPPLE
= 200mV
P-P
(Note 4)
f = 10kHz, V
RIPPLE
= 200mV
P-P
(Note 4)
MIN
70
TYP
95
84
63
3.5
40
±2
±2
-60
dBV
-60
89
dB FS
97
100
103
12
200
-74
dB
-77
0.4
550
550
V/µs
625
625
kHz
dB
µV
RMS
pF
80
±7
±10
dB
kΩ
mV
dB
MAX
UNITS
Click-and-Pop Level
Dynamic Range
DR
Signal-to-Noise Ratio
Noise
Capacitive-Load Drive
SNR
V
n
C
L
Crosstalk
L to R, R to L,
20kHz AES17
BW = 20Hz to 20kHz
Slew Rate
SR
4
_______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
ELECTRICAL CHARACTERISTICS (continued)
(V
DD
= PV
DD
= CPV
DD
= HPV
DD
= HP_EN = V
LDO_EN
(MAX9789 only) = +5V, V
GND
= V
PGND
= V
CPGND
=
SPKR_EN
= V
LDO_SET
(MAX9789 only) = 0V, I
LDO_OUT
(MAX9789 only) = 0, C1 = C2 = C
BIAS
= 1µF. R
L
=
∞,
unless otherwise specified, V
GAIN1
= 0,
V
GAIN2
= 5V (A
VSP
= 10dB, A
VHP
= 3.5dB), T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 2)
PARAMETER
LDO_SET Input Bias Current
(Note 5)
Dropout Voltage (Note 6)
Current Limit
Startup Time
Line Regulation
Load Regulation
Ripple Rejection
Output Voltage Noise
V
IN
= 4.5V to 5.5V, LDO_OUT = 2.5V,
I
LDO_OUT
= 1mA
V
LDO_OUT
= 4.75V,
1mA < I
LDO_OUT
< 120mA
V
RIPPLE
= 200mV
P-P
I
LDO_OUT
= 10mA
f = 1kHz
f = 10kHz
-4.8
SYMBOL
I
SET
V
DO
I
LIM
V
OUT
= 4.75V (fixed
output operation),
T
A
= +25°C
I
OUT
= 50mA
I
OUT
= 120mA
CONDITIONS
MIN
TYP
±20
25
75
300
20
+0.8
0.2
59
42
125
+4.8
MAX
±500
50
mV
150
mA
µs
mV/V
mV/mA
dB
µV
RMS
UNITS
nA
MAX9789/MAX9790
20Hz to 22kHz, C
LDO_OUT
= 2 x 1µF,
I
LDO_OUT
= 120mA
V
INH
V
INL
2
DIGITAL INPUTS (SPKR_EN, HP_EN,
MUTE,
GAIN1, GAIN2, LDO_EN (MAX9789 Only))
Input-Voltage High
Input-Voltage Low
Input Bias Current
V
0.8
±1
V
µA
Note 2:
All devices are 100% production tested at room temperature. All temperature limits are guaranteed by design.
Note 3:
Specified at room temperature with an 8Ω resistive load connected across BTL output for speaker amplifier. Specified at
room temperature with a 32Ω resistive load connected between HPR, HPL, and GND for headphone amplifier. Speaker and
headphone mode transitions are controlled by
SPKR_EN
and HP_EN control pins, respectively.
Note 4:
Amplifier inputs AC-coupled to GND.
Note 5:
Maximum value is due to test limitations.
Note 6:
V
LDO_OUT
= V
LDO_OUTNOMINAL
- 2%.
_______________________________________________________________________________________
5
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
