19-0606; Rev 3; 9/09
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
Features
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 DirectDrive
architecture that produces a ground-referenced output
from a single supply to eliminate the need for large DCblocking capacitors, as well as save cost, board space,
and component height. A high +90dB PSRR and low
0.002% THD+N ensures clean, low-distortion amplification of the audio signal.
♦ Microsoft Windows Vista Compliant
♦ Class AB 2W Stereo BTL Speaker Amplifier
♦ 100mW DirectDrive Headphone Amplifier
Eliminates Costly, Bulky DC-Blocking Capacitors
♦ Excellent RF Immunity
♦ Integrated 120mA LDO (MAX9789)
♦ High +90dB PSRR, Low 0.002% THD+N
♦ Low-Power Shutdown Mode
♦ Click-and-Pop Suppression
♦ Short-Circuit and Thermal-Overload Protection
♦ Available in 32-Pin Thin QFN (5mm x 5mm x
0.8mm) Package
Separate speaker and headphone amplifier control
inputs provide independent shutdown of the speaker
and headphone amplifiers, allowing speaker and headphone amplifiers to be active simultaneously, if
required. The industry-leading click-and-pop suppression 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 independently 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.
Applications
Notebook Computers
Ordering Information
PART
PIN-PACKAGE INTERNAL LDO tON (ms)
32 TQFN-EP*
Yes
MAX9789BETJ+** 32 TQFN-EP*
Yes
25
MAX9789CETJ+
32 TQFN-EP*
Yes
100
MAX9790AETJ+
32 TQFN-EP*
No
100
MAX9789AETJ+
100
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
MAX9789
SPKR_INL
HP_INR
Tablet PCs
Portable Multimedia Players
HP_INL
SPKR_EN
Pin Configurations appear at end of data sheet.
HP_EN
MUTE
GAIN1
GAIN2
Windows Vista is a registered trademark of Microsoft Corp.
DirectDrive is a registered trademark of Maxim Integrated
Products, Inc.
4.5V TO 5.5V
LDO
1.21V TO 4.75V
Simplified Block Diagrams continued at end of data sheet.
________________________________________________________________ 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.
1
MAX9789/MAX9790
General Description
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (VDD, PVDD, HPVDD,
CPVDD to GND) ..................................................-0.3V to +6.0V
GND to PGND, CPGND ......................................................±0.3V
CPVSS, C1N, VSS to GND......................................-6.0V to +0.3V
HPR, HPL to GND ...............................................................±3.0V
Any Other Pin .............................................-0.3V to (VDD + 0.3V)
Duration of OUT_+, OUT_- Short Circuit
to GND or PVDD ......................................................Continuous
Duration of Short Circuit between OUT_+, OUT_and LDO_OUT.........................................................Continuous
Duration of Short Circuit between HPR, HPL and GND,
VSS or HPVDD ..........................................................Continuous
Continuous Current (PVDD, OUT_+, OUT_-, PGND).............1.7A
Continuous Current (CPVDD, C1N, C1P, CPVSS, PVSS,
VDD, HPVDD, LDO_OUT, HPR, HPL) .............................850mA
Continuous Input Current (all other pins) .........................±20mA
Continuous Power Dissipation (TA = +70°C)
32-Pin Thin QFN Single-Layer Board
(derate 18.6mW/°C above +70°C) ..............................1489mW
θJA ...........................................................................53.7°C/W
θJC ...........................................................................19.9°C/W
32-Pin Thin QFN Multilayer Board
(derate 24.9 mW/°C above +70°C) .............................1990mW
θJA ...........................................................................40.2°C/W
θJC ...........................................................................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 fourlayer 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
(VDD = PVDD = CPVDD = HPVDD = HP_EN = VLDO_EN (MAX9789 only) = +5V, VGND = VPGND = VCPGND = SPKR_EN = VLDO_SET
(MAX9789 only) = 0V, ILDO_OUT (MAX9789 only) = 0, C1 = C2 = CBIAS = 1µF. RL = ∞, unless otherwise specified, VGAIN1 = 0,
VGAIN2 = 5V (AVSP = 10dB, AVHP = 3.5dB), TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
GENERAL
Supply Voltage
Headphone Supply Voltage
VDD, PVDD
CPVDD,
HPVDD
Guaranteed by PSRR and LDO Line
Regulation Tests
4.5
5.5
V
Guaranteed by PSRR Test
3.0
5.5
V
SPKR_EN
Quiescent Current
IDD
Shutdown Current
ISHDN
Bias Voltage
VBIAS
Shutdown to Full Operation
tSON
Gain Switching Time
tSW
HP_EN
1 (MAX9789)
0 (MAX9789)
0.1
0.4
mA
1 (MAX9790)
0 (MAX9790)
0.3
6
µA
1
1
7
13
0
0
14
29
0
1
18
40
0.3
6
µA
1.8
1.9
V
SPKR_EN = VDD, HP_EN = LDO_EN = GND
1.7
MAX9789A/MAX9789C/MAX9790A
100
MAX9789B/MAX9790B
25
Channel-to-Channel Gain
Tracking
mA
ms
10
µs
±0.1
dB
SPEAKER AMPLIFIER
Output Power
Total Harmonic Distortion Plus
Noise
2
POUT
THD+N
THD+N = 1%, f = 1kHz,
TA = +25°C
RL = 4Ω
2
RL = 8Ω
1
RL = 8Ω, POUT = 1W, f = 1kHz
0.002
RL = 4Ω, POUT = 1W, f = 1kHz
0.004
_______________________________________________________________________________________
W
%
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
(VDD = PVDD = CPVDD = HPVDD = HP_EN = VLDO_EN (MAX9789 only) = +5V, VGND = VPGND = VCPGND = SPKR_EN = VLDO_SET
(MAX9789 only) = 0V, ILDO_OUT (MAX9789 only) = 0, C1 = C2 = CBIAS = 1µF. RL = ∞, unless otherwise specified, VGAIN1 = 0,
VGAIN2 = 5V (AVSP = 10dB, AVHP = 3.5dB), TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
VDD = 4.5V to 5.5V, TA = +25°C
Power-Supply Rejection Ratio
PSRR
f = 1kHz, 200mVP-P (Note 4)
AV
TYP
72
90
MAX
UNITS
dB
70
f = 10kHz, 200mVP-P (Note 4)
Voltage Gain
MIN
50
GAIN1
GAIN2
0
0
0
1
10
1
0
15.6
1
1
21.6
6
dB
Measured at speaker amplifier inputs
Input Impedance
RIN
Output Offset Voltage
Click-and-Pop Level
Signal-to-Noise Ratio
VOS
KCP
GAIN1
GAIN2
0
0
80
0
1
65
1
0
45
1
1
25
Measured between
OUT_+ and OUT_-,
TA = +25°C
kΩ
±1
±15
±1
±25
mV
MAX9789C
RL = 8Ω, peak voltage, Into shutdown
A-weighted, 32 samples
per second (Notes 3, 4) Out of shutdown
-50
dBV
-50
A-weighted
102
f = 22Hz to 22kHz
99
SNR
RL = 8Ω, POUT = 1W
Noise
Vn
BW = 22Hz to 22kHz
30
µVRMS
Capacitive-Load Drive
CL
No sustained oscillations
200
pF
L to R, R to L, RL = 8Ω, FS = 0.707VRMS,
VOUT = 70.7nVRMS, 20kHz AES17,
BW = 20Hz to 20kHz
-70
dB
1.4
V/µs
Crosstalk
Slew Rate
SR
dB
HEADPHONE AMPLIFIER
Output Power
POUT
Total Harmonic Distortion Plus
Noise
THD+N
THD+N = 1%, f =
1kHz, TA = +25°C
RL = 16Ω
100
RL = 32Ω
55
mW
RL = 32Ω, FS = 0.300VRMS,
VOUT = 210mVRMS, 20kHz AES17,
BW = 20Hz to 20kHz
-77
dB FS
RL = 32Ω, POUT = 40mW, f = 1kHz
0.02
%
RL = 16Ω, POUT = 60mW, f = 1kHz
0.03
RL = 10kΩ, FS = 0.707VRMS,
VOUT = 500mVRMS, 20kHz AES17,
BW = 20Hz to 20kHz
-94
dB FS
_______________________________________________________________________________________
3
MAX9789/MAX9790
ELECTRICAL CHARACTERISTICS (continued)
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
ELECTRICAL CHARACTERISTICS (continued)
(VDD = PVDD = CPVDD = HPVDD = HP_EN = VLDO_EN (MAX9789 only) = +5V, VGND = VPGND = VCPGND = SPKR_EN = VLDO_SET
(MAX9789 only) = 0V, ILDO_OUT (MAX9789 only) = 0, C1 = C2 = CBIAS = 1µF. RL = ∞, unless otherwise specified, VGAIN1 = 0,
VGAIN2 = 5V (AVSP = 10dB, AVHP = 3.5dB), TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
HPVDD = 3V to 5.5V, TA = +25°C
Power-Supply Rejection Ratio
PSRR
84
AV
Measured at headphone amplifier inputs
Output Offset Voltage
VOS
TA = +25°C
Click-and-Pop Level
KCP
SNR
RL = 32Ω, f = 1kHz, A-weighted,
FS = 0.300VRMS, VOUT = 300µVRMS
89
RL = 10kΩ, f = 1kHz, A-weighted,
FS = 0.707VRMS, VOUT = 707µVRMS
97
RL = 32Ω,
POUT = 60mW
dB
L to R, R to L,
20kHz AES17
BW = 20Hz to 20kHz
kΩ
mV
dB FS
100
103
No sustained oscillations
dB
80
±7
±10
dBV
A-weighted
CL
UNITS
-60
22Hz to 22kHz
Capacitive-Load Drive
dB
12
µVRMS
200
pF
RL = 32Ω,
FS = 0.300VRMS,
VOUT = 30mVRMS
-74
RL = 10kΩ,
FS = 0.707VRMS,
VOUT = 70.7mVRMS
-77
dB
SR
fOSC
40
±2
±2
-60
BW = 22Hz to 22kHz
Charge-Pump Frequency
20
MAX9789C
RL = 32Ω, peak voltage, Into shutdown
A-weighted, 32 samples
per second (Notes 3, 4) Out of shutdown
Vn
Slew Rate
MAX
3.5
Noise
Crosstalk
95
63
RIN
Signal-to-Noise Ratio
70
f = 10kHz, VRIPPLE = 200mVP-P (Note 4)
Input Impedance
DR
TYP
f = 1kHz, VRIPPLE = 200mVP-P (Note 4)
Voltage Gain
Dynamic Range
MIN
500
0.4
550
625
V/µs
MAX9789C
475
550
625
Inferred from line regulation
4.5
IOUT = 0mA
0.1
0.4
IOUT = 120mA
-40
kHz
LOW-DROPOUT LINEAR REGULATOR
Regulator Input Voltage Range
VDD
Ground Current
IGND
Output Current
IOUT
120
Crosstalk
VOUT = 4.75V, IOUT = 0mA, f = 1kHz,
speaker POUT = 2W, speaker RL = 4Ω
Fixed Output Voltage Accuracy
IOUT = 1mA
Adjustable Output Voltage Range
LDO_SET Reference Voltage
LDO_SET Dual-Mode Threshold
4
VSET
5.5
MAX9789C
-95
1.21
1.18
1.18
1.21
1.21
200
_______________________________________________________________________________________
mA
mA
dB
±1.5
±3.0
MAX9789C
V
4.75
1.23
1.25
%
V
V
mV
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
(VDD = PVDD = CPVDD = HPVDD = HP_EN = VLDO_EN (MAX9789 only) = +5V, VGND = VPGND = VCPGND = SPKR_EN = VLDO_SET
(MAX9789 only) = 0V, ILDO_OUT (MAX9789 only) = 0, C1 = C2 = CBIAS = 1µF. RL = ∞, unless otherwise specified, VGAIN1 = 0,
VGAIN2 = 5V (AVSP = 10dB, AVHP = 3.5dB), TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
LDO_SET Input Bias Current
(Note 5)
ISET
Dropout Voltage (Note 6)
VDO
Current Limit
CONDITIONS
VOUT = 4.75V (fixed
output operation),
TA = +25°C
MIN
TYP
MAX
UNITS
±20
±500
nA
IOUT = 50mA
25
50
IOUT = 120mA
75
150
mV
ILIM
Startup Time
Line Regulation
VIN = 4.5V to 5.5V, LDO_OUT = 2.5V,
ILDO_OUT = 1mA
Load Regulation
VLDO_OUT = 4.75V,
1mA < ILDO_OUT < 120mA
Ripple Rejection
VRIPPLE = 200mVP-P
ILDO_OUT = 10mA
Output Voltage Noise
-4.8
300
mA
20
µs
+0.8
+4.8
0.2
f = 1kHz
59
f = 10kHz
42
20Hz to 22kHz, CLDO_OUT = 2 x 1µF,
ILDO_OUT = 120mA
125
mV/V
mV/mA
dB
µVRMS
DIGITAL INPUTS (SPKR_EN, HP_EN, MUTE, GAIN1, GAIN2, LDO_EN (MAX9789 Only))
Input-Voltage High
VINH
Input-Voltage Low
VINL
Input Bias Current
2
V
0.8
V
±1
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: VLDO_OUT = VLDO_OUTNOMINAL - 2%.
_______________________________________________________________________________________
5
MAX9789/MAX9790
ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics
(VDD = PVDD = CPVDD = HPVDD = LDO_EN = +5V, VGND = VPGND = VCPGND = VLDO_SET = 0V, C1 = C2 = CBIAS = CIN = 1µF. RL =
∞, unless otherwise specified, GAIN1 = 0, GAIN2 = 1 (AVSP = 10dB, AVHP = 3.5dB), measurement BW = 20kHz AES17, TA = +25°C,
unless otherwise noted. Headphone mode: SPKR_EN = 1, HP_EN = 0. Speaker mode: SPKR_EN = 0, HP_EN = 1.)
-80
-90
MAX9789 toc03
10
RL = 10kΩ
1
-80
fIN = 20Hz
0.1
fIN = 10kHz
0.01
-90
-100
fIN = 1kHz
0.001
-100
100
1k
10k
100k
10
100
1k
10k
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT VOLTAGE (HEADPHONE MODE)
CROSSTALK
vs. FREQUENCY (HEADPHONE MODE)
0
MAX9789 toc04
-20
CROSSTALK (dB)
1
fIN = 20Hz
0.1
fIN = 10kHz
FS = 0.707VRMS
VOUT = -20dB FS
RL = 10kΩ
-10
-30
-40
-50
LEFT TO RIGHT
-60
-70
0.01
-80
fIN = 1kHz
-90
0.001
RIGHT TO LEFT
-100
0
0.5
1.0
1.5
2.0
10
100
1k
1.0
1.5
2.0
HEADPHONE OUTPUT SPECTRUM
CROSSTALK (dB)
HPVDD = 3V
RL = 10kΩ
0.5
OUTPUT VOLTAGE (VRMS)
FREQUENCY (Hz)
10
0
100k
10k
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
FS = 0.300VRMS
VOUT = -60dB FS
RL = 10kΩ
0
100k
5k
10k
15k
MAX9789 toc06
10
MAX9789 toc05
-110
20k
OUTPUT VOLTAGE (VRMS)
FREQUENCY (Hz)
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (SPEAKER MODE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (SPEAKER MODE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (SPEAKER MODE)
VOUT = -3dB FS
-80
-80
-75
VOUT = -3dB FS
MAX9789 toc09
-75
MAX9789 toc07
-75
MAX9789 toc08
THD+N (%)
HPVDD = 3V
FS = 0.707VRMS
VOUT = -3dB FS
RL = 10kΩ
-70
THD+N (dB FS)
THD+N (dB FS)
-70
-60
THD+N (%)
FS = 0.707VRMS
VOUT = -3dB FS
RL = 10kΩ
MAX9789 toc01
-60
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT VOLTAGE (HEADPHONE MODE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (HEADPHONE MODE)
MAX9789 toc02
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (HEADPHONE MODE)
VOUT = -3dB FS
-80
-85
-90
THD+N (dB FS)
THD+N (dB FS)
-85
THD+N (dB FS)
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
-85
-90
-90
-95
-100
-95
-95
FS = 0.707VRMS
RL = 3Ω
-100
-100
10
100
1k
FREQUENCY (Hz)
6
10k
100k
-105
FS = 0.707VRMS
RL = 4Ω
10
100
FS = 0.707VRMS
RL = 8Ω
-110
1k
FREQUENCY (Hz)
10k
100k
10
100
1k
FREQUENCY (Hz)
_______________________________________________________________________________________
10k
100k
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
RL = 3Ω
10
fIN = 10kHz
0.1
THD+N (%)
0.1
RL = 8Ω
1
1
THD+N (%)
THD+N (%)
1
RL = 4Ω
MAX9789 toc12
10
MAX9789 toc10
10
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (SPEAKER MODE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (SPEAKER MODE)
MAX9789 toc11
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (SPEAKER MODE)
fIN = 10kHz
0.1
fIN = 10kHz
fIN = 20Hz
fIN = 1kHz
0.01
fIN = 1kHz
0.001
fIN = 20Hz
0.001
0.5
1.0
1.5
2.0
2.5
3.0
0.5
1.0
1.5
2.0
0.001
0
2.5
0.5
1.0
1.5
OUTPUT POWER (W)
OUTPUT POWER (W)
OUTPUT POWER (W)
CROSSTALK
vs. FREQUENCY (SPEAKER MODE)
SPEAKER OUTPUT SPECTRUM
OUTPUT POWER vs. LOAD RESISTANCE
(SPEAKER MODE)
CROSSTALK (dB)
-30
-40
-50
LEFT TO RIGHT
RIGHT TO LEFT
-70
-80
-90
-100
10
100
1k
10k
100k
FS = 0.707VRMS
VOUT = -60dB FS
RL = 8Ω
THD+N = 10%
2.0
1.5
1.0
0
0
5k
10k
15k
FREQUENCY (Hz)
20k
1
10
RL (Ω)
100
POWER-SUPPLY REJECTION RATIO
(SPEAKER MODE)
0
MAX9789 toc16
VRIPPLE = 200mVP-P
OUTPUT REFERRED
-10
-20
-30
1.00
PSRR (dB)
POWER DISSIPATION PER CHANNEL (W)
1.25
2.5
THD+N = 1%
POWER DISSIPATION PER CHANNEL
vs. OUTPUT POWER (SPEAKER MODE)
fIN = 1kHz
fIN = 1kHz
3.0
0.5
FREQUENCY (Hz)
1.50
3.5
MAX9789 toc17
-20
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
OUTPUT POWER (W)
FS = 0.707VRMS
VOUT = -20dB FS
RL = 8Ω
MAX9789 toc14
0
-10
-60
0
MAX9789 toc13
0
fIN = 1kHz
MAX9789 toc15
fIN = 20Hz
CROSSTALK (dB)
0.01
0.01
RL = 4Ω
0.75
0.50
-40
-50
-60
-70
-80
RL = 8Ω
0.25
-90
0
100
0
0.5
1.0
1.5
OUTPUT POWER PER CHANNEL (W)
2.0
10
100
1k
10k
FREQUENCY (Hz)
100k
_______________________________________________________________________________________
7
MAX9789/MAX9790
Typical Operating Characteristics (continued)
(VDD = PVDD = CPVDD = HPVDD = LDO_EN = +5V, VGND = VPGND = VCPGND = VLDO_SET = 0V, C1 = C2 = CBIAS = CIN = 1µF. RL =
∞, unless otherwise specified, GAIN1 = 0, GAIN2 = 1 (AVSP = 10dB, AVHP = 3.5dB), measurement BW = 20kHz AES17, TA = +25°C,
unless otherwise noted. Headphone mode: SPKR_EN = 1, HP_EN = 0. Speaker mode: SPKR_EN = 0, HP_EN = 1.)
Typical Operating Characteristics (continued)
(VDD = PVDD = CPVDD = HPVDD = LDO_EN = +5V, VGND = VPGND = VCPGND = VLDO_SET = 0V, C1 = C2 = CBIAS = CIN = 1µF. RL =
∞, unless otherwise specified, GAIN1 = 0, GAIN2 = 1 (AVSP = 10dB, AVHP = 3.5dB), measurement BW = 20kHz AES17, TA = +25°C,
unless otherwise noted. Headphone mode: SPKR_EN = 1, HP_EN = 0. Speaker mode: SPKR_EN = 0, HP_EN = 1.)
SPEAKER STARTUP WAVEFORM
SPEAKER STARTUP WAVEFORM
MAX9789 toc18
MAX9789 toc19
MAX9789B/MAX9790B
MAX9789A/MAX9789C/MAX9790A
SPKR_EN
5V/div
SPKR_EN
5V/div
OUT_+ AND OUT_2V/div
OUT_+ AND OUT_2V/div
OUT_+ - OUT_100mV/div
OUT_+ - OUT_100mV/div
20ms/div
20ms/div
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (HEADPHONE MODE)
SPEAKER SHUTDOWN WAVEFORM
MAX9789 toc20
SPKR_EN
5V/div
-70
OUT_+ AND OUT_2V/div
-80
MAX9789 toc21
-65
THD+N (dB FS)
-75
VOUT = -3dB FS
-85
-90
-95
OUT_+ - OUT_100mV/div
-100
FS = 0.300VRMS
RL = 32Ω
-105
-110
20ms/div
10
100
1k
10k
100k
FREQUENCY (Hz)
-80
-85
-90
-70
-75
VOUT = -3dB FS
-80
-85
-90
-85
-90
-95
-95
-100
-100
-100
HPVDD = 3V
FS = 0.300VRMS
RL = 32Ω
-110
10
100
FS = 0.300VRMS
RL = 16Ω
-105
-110
1k
FREQUENCY (Hz)
10k
100k
10
100
VOUT = -3dB FS
-80
-95
-105
MAX9789 toc24
-75
THD+N (dB FS)
VOUT = -3dB FS
-70
THD+N (dB FS)
-75
-65
MAX9789 toc23
-70
8
-65
MAX9789 toc22
-65
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (HEADPHONE MODE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (HEADPHONE MODE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (HEADPHONE MODE)
THD+N (dB FS)
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
HPVDD = 3V
FS = 0.300VRMS
RL = 16Ω
-105
-110
1k
FREQUENCY (Hz)
10k
100k
10
100
1k
FREQUENCY (Hz)
_______________________________________________________________________________________
10k
100k
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
MAX9789 toc27
10
MAX9789 toc26
10
MAX9789 toc25
10
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (HEADPHONE MODE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (HEADPHONE MODE)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (HEADPHONE MODE)
f = 10kHz
50
100
150
0.1
f = 20Hz
RL = 32Ω
0.01
20
0
200
40
60
80
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER (HEADPHONE MODE)
CROSSTALK
vs. FREQUENCY (HEADPHONE MODE)
MAX9789 toc28
0
0.1
f = 1kHz
AMPLITUDE (dB)
CROSSTALK (dB)
THD+N (%)
f = 20Hz
-40
-50
-60
LEFT TO RIGHT
-70
-80
-90
HPVDD = 3V
RL = 32Ω
0.01
40
60
80
RIGHT TO LEFT
-110
100
10
100
OUTPUT POWER (mW)
1k
100k
10k
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
0
5
15
20
OUTPUT POWER vs. LOAD RESISTANCE
(HEADPHONE MODE)
100
HPVDD = 3V
fIN = 1kHz
OUTPUT POWER (mW)
fIN = 1kHz
10
FREQUENCY (kHz)
OUTPUT POWER vs. LOAD RESISTANCE
(HEADPHONE MODE)
150
150
FS = 0.707VRMS
VOUT = -60dB FS
RL = 32Ω
FREQUENCY (Hz)
MAX9789 toc31
20
OUTPUT POWER (mW)
0
-100
100
HEADPHONE OUTPUT SPECTRUM
-30
f = 10kHz
1
FS = 0.300VRMS
VOUT = -20dB FS
RL = 32Ω
-20
50
0
OUTPUT POWER (mW)
OUTPUT POWER (mW)
-10
HPVDD = 3V
RL = 16Ω
0.01
100
OUTPUT POWER (mW)
10
f = 1kHz
MAX9789 toc30
0.01
f = 20Hz
100
THD+N = 10%
50
MAX9789 toc32
RL = 16Ω
0
f = 1kHz
0.1
f = 1kHz
1
THD+N (%)
THD+N (%)
THD+N (%)
f = 20Hz
0.1
f = 10kHz
1
MAX9789 toc29
f = 10kHz
1
THD+N = 10%
50
THD+N = 1%
THD+N = 1%
0
0
10
100
RL (Ω)
1000
10
100
RL (Ω)
1000
_______________________________________________________________________________________
9
MAX9789/MAX9790
Typical Operating Characteristics (continued)
(VDD = PVDD = CPVDD = HPVDD = LDO_EN = +5V, VGND = VPGND = VCPGND = VLDO_SET = 0V, C1 = C2 = CBIAS = CIN = 1µF. RL =
∞, unless otherwise specified, GAIN1 = 0, GAIN2 = 1 (AVSP = 10dB, AVHP = 3.5dB), measurement BW = 20kHz AES17, TA = +25°C,
unless otherwise noted. Headphone mode: SPKR_EN = 1, HP_EN = 0. Speaker mode: SPKR_EN = 0, HP_EN = 1.)
Typical Operating Characteristics (continued)
(VDD = PVDD = CPVDD = HPVDD = LDO_EN = +5V, VGND = VPGND = VCPGND = VLDO_SET = 0V, C1 = C2 = CBIAS = CIN = 1µF. RL =
∞, unless otherwise specified, GAIN1 = 0, GAIN2 = 1 (AVSP = 10dB, AVHP = 3.5dB), measurement BW = 20kHz AES17, TA = +25°C,
unless otherwise noted. Headphone mode: SPKR_EN = 1, HP_EN = 0. Speaker mode: SPKR_EN = 0, HP_EN = 1.)
POWER DISSIPATION vs. OUTPUT POWER
(HEADPHONE MODE)
RL = 16Ω
RL = 32Ω
50
25
0
125
MAX9789 toc34
275
250
225
200
175
150
125
100
75
POWER DISSIPATION PER CHANNEL
vs. OUTPUT POWER (HEADPHONE MODE)
POWER DISSIPATION PER CHANNEL (mW)
MAX9789 toc33
HPVDD = 3V
100
75
RL = 16Ω
50
RL = 32Ω
25
0
0
25
50
75
100
OUTPUT POWER PER CHANNEL (mW)
125
0
20
40
60
OUTPUT POWER PER CHANNEL (mW)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (HEADPHONE MODE)
HEADPHONE OUTPUT POWER vs. HPVDD
0
MAX9789 toc35
125
100
VRIPPLE = 200mVP-P
OUTPUT REFERRED
-10
-20
-30
RL = 16Ω
PSRR (dB)
75
50
-40
-50
-60
-70
RL = 32Ω
25
-80
THD+N = 1%
fIN = 1kHz
-90
-100
0
3.0
3.5
4.0
HPVDD (V)
4.5
5.0
HEADPHONE STARTUP WAVEFORM
10
100
1k
10k
FREQUENCY (Hz)
MAX9789 toc38
MAX9789B/MAX9790B
MAX9789A/MAX9789C/MAX9790A
20ms/div
100k
HEADPHONE STARTUP WAVEFORM
MAX9789 toc37
10
80
MAX9789 toc36
POWER DISSIPATION PER CHANNEL (mW)
300
HEADPHONE OUTPUT POWER (mW)
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
HP_EN
5V/div
HP_EN
5V/div
HP_
500mV/div
HP_
500mV/div
20ms/div
______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
HEADPHONE SHUTDOWN WAVEFORM
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX9789 toc39
HP_EN
HP_
500mV/div
15
SUPPLY CURRENT (mA)
5V/div
MAX9789 toc40
20
SPKR_EN = 0
HP_EN = 1
10
SPKR_EN = 0
HP_EN = 0
SPKR_EN = 1
HP_EN = 0
5
SPKR_EN = 1
HP_EN = 1
0
-5
20ms/div
4.50
0.1
VLDO_OUT = 4.75V
1.5
1.0
0.5
0
-0.5
-1.0
-1.5
-2.0
0
4.75
5.00
5.25
SUPPLY VOLTAGE (V)
0
5.50
75
100
ILOAD (mA)
125
0.05
0
-0.05
2.0
LDO OUTPUT VOLTAGE ACCURACY (%)
MAX9789 toc43
VLDO_OUT = 4.75V
ILDO_OUT = 0A
50
150
LDO OUTPUT VOLTAGE ACCURACY
vs. TEMPERATURE
LDO OUTPUT VOLTAGE ACCURACY
vs. AMPLIFIER OUTPUT POWER
0.10
25
MAX9789 toc44
4.50
LDO OUTPUT VOLTAGE ACCURACY (%)
MAX9789 toc42
MAX9789 toc41
0.2
2.0
LDO OUTPUT VOLTAGE ACCURACY (%)
SHUTDOWN CURRENT (μA)
SPKR_EN = 5V
HP_EN = 0
LDO_EN = 0 (MAX9789)
5.50
LDO OUTPUT VOLTAGE ACCURACY
vs. ILOAD
SHUTDOWN CURRENT vs. SUPPLY VOLTAGE
0.3
4.75
5.00
5.25
SUPPLY VOLTAGE (V)
ILDO_OUT = 1mA
1.5
1.0
0.5
0
-0.5
-1.0
-1.5
-2.0
-0.10
0
0.5
1.0
1.5
2.0
2.5
AMPLIFIER OUTPUT POWER (W)
3.0
-40
-15
10
35
TEMPERATURE (°C)
60
85
______________________________________________________________________________________
11
MAX9789/MAX9790
Typical Operating Characteristics (continued)
(VDD = PVDD = CPVDD = HPVDD = LDO_EN = +5V, VGND = VPGND = VCPGND = VLDO_SET = 0V, C1 = C2 = CBIAS = CIN = 1µF. RL =
∞, unless otherwise specified, GAIN1 = 0, GAIN2 = 1 (AVSP = 10dB, AVHP = 3.5dB), measurement BW = 20kHz AES17, TA = +25°C,
unless otherwise noted. Headphone mode: SPKR_EN = 1, HP_EN = 0. Speaker mode: SPKR_EN = 0, HP_EN = 1.)
Typical Operating Characteristics (continued)
(VDD = PVDD = CPVDD = HPVDD = LDO_EN = +5V, VGND = VPGND = VCPGND = VLDO_SET = 0V, C1 = C2 = CBIAS = CIN = 1µF. RL =
∞, unless otherwise specified, GAIN1 = 0, GAIN2 = 1 (AVSP = 10dB, AVHP = 3.5dB), measurement BW = 20kHz AES17, TA = +25°C,
unless otherwise noted. Headphone mode: SPKR_EN = 1, HP_EN = 0. Speaker mode: SPKR_EN = 0, HP_EN = 1.)
60
50
VLDO_OUT = 3.3V
40
30
-30
-40
-60
20
-70
10
-80
0
VLDO_OUT = 4.75V
-50
25
50
75
100
150
125
1
0.1
VLDO_OUT = 3.3V
0.01
-90
0
MAX9789 toc47
-20
RIPPLE REJECTION (dB)
VLDO_OUT = 4.75V
70
VRIPPLE = 200mVP-P
IOUT = 10mA
OUTPUT REFERRED
-10
10
OUTPUT NOISE (μV√Hz)
MAX9789 toc45
90
80
OUTPUT NOISE vs. FREQUENCY
RIPPLE REJECTION vs. FREQUENCY
0
MAX9789 toc46
DROPOUT VOLTAGE vs. ILOAD
100
DROPOUT VOLTAGE (mV)
10
ILOAD (mA)
100
1k
10
100k
10k
100
1k
10k
FREQUENCY (Hz)
FREQUENCY (Hz)
LINE-TRANSIENT RESPONSE
LDO LOAD-TRANSIENT RESPONSE
MAX9789 toc48
MAX9789 toc49
VDD
1V/div
5.5V
ILDO_OUT
15mA/div
4.5V
LDO_OUT
(AC-COUPLED)
20mV/div
AC-COUPLED
VLDO_OUT
10mV/div
1ms/div
20ms/div
LDO SHUTDOWN RESPONSE
-20
ILOAD = 0mA
VLDO_OUT = 4.75V
POUT = 2W
RL = 4Ω
IOUT = 0mA
-30
LDO_EN
2V/div
-40
VLDO_OUT
2V/div
-50
-60
-70
RIGHT SPEAKER TO LDO
-80
-90
-100
-110
200ms/div
12
MAX9789 toc51
LDO CROSSTALK vs. FREQUENCY
MAX9789 toc50
CROSSTALK (dB)
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
LEFT SPEAKER TO LDO
-120
10
100
1k
10k
FREQUENCY (Hz)
______________________________________________________________________________________
100k
100k
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
PIN
NAME
FUNCTION
MAX9789
MAX9790
1
—
LDO_SET
2
2
SPKR_INR Right-Channel Speaker Amplifier Input
3
3
SPKR_INL
4
—
LDO_EN
5, 21
5, 21
PGND
Power Ground. Star-connect to GND.
6
6
OUTL+
Left-Channel Speaker Amplifier Output, Positive Phase
7
7
OUTL-
Left-Channel Speaker Amplifier Output, Negative Phase
8, 18
8, 18
PVDD
Speaker Amplifier Power-Supply Input. Bypass with a 0.1µF capacitor to PGND.
9
9
CPVDD
10
10
C1P
11
11
CPGND
12
12
C1N
13
13
CPVSS
14
14
PVSS
15
15
HPR
Right-Channel Headphone Amplifier Output
16
16
HPL
Left-Channel Headphone Amplifier Output
17
17
HPVDD
Headphone Amplifier Positive Power Supply. Connect a 10µF capacitor between HPVDD
and PGND.
19
19
OUTR-
Right-Channel Speaker Amplifier Output, Negative Phase
20
20
OUTR+
Right-Channel Speaker Amplifier Output, Positive Phase
22
22
HP_EN
Active-High Headphone Amplifier Enable
23
23
SPKR_EN
24
24
BIAS
Common-Mode Bias Voltage. Bypass with a 1µF capacitor to GND.
25
25
MUTE
Active-Low Mute Enable. Mutes speaker and headphone amplifiers.
26
26
HP_INR
Right-Channel Headphone Amplifier Input
27
27
HP_INL
Left-Channel Headphone Amplifier Input
28
4, 28
GND
29
—
LDO_OUT
30
30
VDD
31
31
GAIN1
Speaker Amplifier Gain Select 1
32
32
GAIN2
Speaker Amplifier Gain Select 2
—
1, 29
N.C.
EP
EP
EP
Regulator Feedback Input. Connect to GND for 4.75V fixed output. Connect to a resistordivider for adjustable output. See Figure 1.
Left-Channel Speaker Amplifier Input
LDO Enable. Connect LDO_EN to VDD to enable the LDO.
Charge-Pump Power Supply. Connect a 1µF capacitor between CPVDD and PGND.
Charge-Pump Flying Capacitor Positive Terminal. Connect a 1µF capacitor between C1P
to C1N.
Charge-Pump Ground. Connect directly to PGND plane.
Charge-Pump Flying Capacitor Negative Terminal. Connect a 1µF capacitor between C1P
to C1N.
Charge-Pump Output. Connect to PVSS.
Headphone Amplifier Negative Power Supply. Connect a 1µF capacitor between PVSS and
PGND.
Active-Low Speaker Amplifier Enable
Signal Ground. Star-connect to PGND.
LDO Output. Bypass with two 1µF capacitors to GND.
Positive Power Supply and LDO Input (MAX9789). Bypass with one 0.1µF capacitor and
two 1µF capacitors to GND (MAX9789). Bypass with one 0.1µF capacitor and one 1µF
capacitor to GND (MAX9790).
No Connection. Not internally connected.
Exposed Paddle. Connect to GND.
______________________________________________________________________________________
13
MAX9789/MAX9790
Pin Description
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
Detailed Description
The MAX9789/MAX9790 combine a 2W BTL speaker
amplifier with an 100mW DirectDrive headphone amplifier. These devices feature comprehensive click-and-pop
suppression and programmable four-level speaker amplifier gain control. The MAX9789/MAX9790 feature high
+90dB PSRR, low 0.002% THD+N, industry-leading clickand-pop performance, low-power shutdown mode, and
excellent RF immunity. The MAX9789 incorporates an
integrated LDO that serves as a clean power supply for a
CODEC or other circuits.
The MAX9789/MAX9790 is Microsoft Windows Vista compliant. See Table 1 for a comparison of the Microsoft
Windows Vista premium mobile specifications and
MAX9789/MAX9790 specifications.
The speaker amplifiers use BTL architecture, doubling the
voltage drive to the speakers and eliminating the need for
DC-blocking capacitors. The output consists of two signals, identical in magnitude, but 180° out of phase.
The headphone amplifiers use Maxim’s DirectDrive
architecture to eliminate the bulky output DC-blocking
capacitors required by traditional headphone amplifiers. A charge pump inverts a positive supply (CPVDD)
to create a negative supply (CPVSS). The headphone
amplifiers operate from these bipolar supplies with their
outputs biased about GND. The benefit of the GND
bias is that the amplifier outputs no longer have a DC
component (typically VDD / 2). This feature eliminates
the large DC-blocking capacitors required with conven-
tional headphone amplifiers to conserve board space
and system cost, as well as improve low-frequency
response.
The MAX9789/MAX9790 feature programmable speaker amplifier gain, allowing the speaker gain to be set by
the logic voltages applied to GAIN1 and GAIN2, while
the headphone amplifiers feature a fixed 3.5dB gain.
Both amplifiers feature an undervoltage lockout that
prevents operation from an insufficient power supply
and click-and-pop suppression that eliminates audible
transients on startup and shutdown. The amplifiers
include thermal overload and short-circuit protection.
An additional feature of the speaker amplifiers is that
there is no phase inversion from input to output.
Low-Dropout Linear Regulator
(MAX9789 Only)
The MAX9789’s low-dropout (LDO) linear regulator can
be used to provide a clean power supply to a CODEC
or other circuitry. The LDO can be enabled independently of the audio amplifiers. Set LDO_EN = VDD to
enable the LDO or set LDO_EN = GND to disable the
LDO. The LDO is capable of providing up to 120mA
continuous current and features Maxim’s Dual Mode™
feedback, easily enabling a fixed 4.75V output or a
user-adjustable output. When LDO_SET is connected
to GND, the output is internally set to 4.75V. The output
voltage can be adjusted from 1.21V to 4.75V by connecting two external resistors as a voltage divider, at
LDO_SET (Figure 1).
Table 1. Windows Premium Mobile Vista Specifications vs. MAX9789/MAX9790
Specifications
DEVICE TYPE
WINDOWS PREMIUM MOBILE Vista
SPECIFICATIONS
MAX9789/MAX9790
TYPICAL PERFORMANCE
≤ -65dB FS
[20Hz, 20kHz]
-94dB FS
[20Hz, 20kHz]
≤ -80dB FS,
A-weighted
≤ -50dB
[20Hz, 20kHz]
≤ -45dB FS
[20Hz, 20kHz]
-97dB FS,
A-weighted
-77dB
[20Hz, 20kHz]
-77dB FS
[20Hz, 20kHz]
Dynamic range with
signal present
≤ -60dB FS,
A-weighted
-89dB FS,
A-weighted
Headphone output
crosstalk
≤ -50dB
[20Hz, 20kHz]
-74dB
[20Hz, 20kHz]
REQUIREMENT
THD+N
Analog Line Output
Jack (RL = 10kΩ,
FS = 0.707VRMS)
Dynamic range with
signal present
Line output crosstalk
THD+N
Analog Headphone
Out Jack (RL = 32Ω,
FS = 0.300VRMS)
Note: THD+N, DYNAMIC RANGE, and CROSSTALK should be measured in accordance with AES-17 audio measurements standards.
Dual Mode is a trademark of Maxim Integrated Products, Inc.
14
______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
R1 ⎞
⎛
VLDO _ OUT = VLDO _ SET ⎜1 +
⎟
⎝ R2 ⎠
where VLDO_SET = 1.21V.
To simplify resistor selection:
⎛ VLDO _ OUT ⎞
R1 = R2⎜
− 1⎟
⎝
⎠
1.21
Since the input bias current at LDO_SET is typically
less than 500nA (max), large resistance values can be
used for R1 and R2 to minimize power consumption
without compromising accuracy. The parallel combination of R1 and R2 should be less than 1MΩ.
DirectDrive
Conventional single-supply headphone amplifiers have
their outputs biased about a nominal DC voltage
(VDD / 2) for maximum dynamic range. Large coupling
capacitors are needed to block this DC bias from the
headphones. Without these capacitors, a significant
amount of DC current flows to the headphone, resulting
in unnecessary power dissipation and possible damage to both headphone and headphone amplifier.
Maxim’s DirectDrive architecture uses a charge pump
to create an internal negative supply voltage. It allows
the MAX9789/MAX9790 headphone amplifier output to
be biased about GND. With no DC component, there is
no need for the large DC-blocking capacitors. Instead
of two large capacitors (330µF typically required to
meet Vista magnitude response specifications), the
MAX9789/MAX9790 charge pump requires only two
small 1µF ceramic capacitors, conserving board
space, reducing cost, and improving the low-frequency
response of the headphone amplifier.
Previous attempts to eliminate the output coupling
capacitors involved biasing the headphone return
(sleeve) to the DC bias voltage of the headphone
amplifiers. This method raised some issues:
• The sleeve is typically grounded to the chassis.
Using this biasing approach, the sleeve must be isolated from system ground, complicating product
design.
• During an ESD strike, the amplifier’s ESD structures
are the only path to system ground. The amplifier
must be able to withstand the full ESD strike.
• When using the headphone jack as a line out to
other equipment, the bias voltage on the sleeve may
conflict with the ground potential from other equipment, resulting in large ground loop current and
possible damage to the amplifiers.
Low-Frequency Response
In addition to the cost and size disadvantages, the DCblocking capacitors limit the low-frequency response of
the amplifier and distort the audio signal:
• The impedance of the headphone load and the DCblocking capacitor form a highpass filter with the
-3dB point determined by:
f − 3dB =
TO HDA
CODEC
LDO_OUT
R1
1μF
MAX9789
LDO_SET
R2
GND
1μF
1
2πRLCOUT
where RL is the impedance of the headphone and
COUT is the value of the DC-blocking capacitor.
• The highpass filter is required by conventional singleended, single-supply headphone amplifier to block
the midrail DC component of the audio signal from the
headphones. Depending on the -3dB point, the filter
can attenuate low-frequency signals within the audio
band. Larger values of COUT reduce the attenuation,
but are physically larger, more expensive capacitors.
Figure 2 shows the relationship between the size of
COUT and the resulting low-frequency attenuation.
Note the Vista’s magnitude response specification
calls for a -3dB point at 20Hz at the headphone jack.
The -3dB point at 20Hz for a 32Ω headphone requires
a 330µF blocking capacitor (Table 2).
Figure 1. Adjustable Output Using External Feedback
Resistors.
______________________________________________________________________________________
15
MAX9789/MAX9790
The output voltage is set by the following equation:
ADDITIONAL THD+N DUE TO
DC-BLOCKING CAPACITORS
LOW-FREQUENCY ROLLOFF
(RL = 16Ω)
10
0
COUT = 100μF
RL = 16Ω
-3
1
DirectDrive
-6
-9
330μF
THD+N (%)
ATTENUATION (dB)
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
-12
220μF
-15
100μF
-18
-21
33μF
0.1
TANTALUM
0.01
0.001
-24
ALUM/ELEC
-27
0.0001
-30
1
10
100
1k
10k
10
100k
100
1k
10k
100k
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 2. Low-Frequency Attenuation of Common DC-Blocking
Capacitor Values
Figure 3. Distortion Contributed by DC-Blocking Capacitors
• The voltage coefficient of the capacitor, the change
in capacitance due to a change in the voltage
across the capacitor, distorts the audio signal. At
frequencies around the -3dB point, this effect is
maximized and the voltage coefficient appears as
frequency-dependent distortion. Figure 3 shows the
THD+N introduced by two different capacitor
dielectrics. Note that around the -3dB point, THD+N
increases dramatically.
speed that minimizes noise generated by switching
transients. Limiting the switching speed of the charge
pump minimizes the di/dt noise caused by the parasitic
bond wire and trace inductance.
• The combination of low-frequency attenuation and frequency-dependent distortion compromises audio
reproduction. DirectDrive improves low-frequency
reproduction in portable audio equipment that emphasizes low-frequency effects, such as multimedia laptops, MP3, CD, and DVD players (See Table 2).
Table 2. Low-Frequency Rolloff
COUT (µF)
f-3dB (Hz)
RL = 16Ω
RL = 32Ω
22
452
226
33
301
151
100
99
50
220
45
23
330*
30
15
470
21
*Vista requirement for 32Ω load.
11
Charge Pump
The MAX9789/MAX9790 feature a low-noise charge
pump. The 550kHz switching frequency is well beyond
the audio range, and does not interfere with the audio
signals. The switch drivers feature a controlled switching
16
BIAS
The MAX9789/MAX9790 feature an internally generated, power-supply independent, common-mode bias
voltage of 1.8V referenced to GND. BIAS provides both
click-and-pop suppression and sets the DC bias level
for the amplifiers. The BIAS pin should be bypassed to
GND with a 1µF capacitor. No external load should be
applied to BIAS. Any load lowers the BIAS voltage,
affecting the overall performance of the device.
Headphone and Speaker Amplifier Gain
The MAX9789/MAX9790 feature programmable speaker amplifier gain, set by the logic voltages applied to
pins GAIN1 and GAIN2. Table 3 shows the logic combinations that can be applied to pins GAIN1 and GAIN2
and their affects on the speaker amplifier gain. The
headphone amplifier gain is fixed at 3.5dB.
Table 3. MAX9789/MAX9790
Programmable Gain Settings
MAX9789/MAX9790
GAIN1
GAIN2
SPEAKER MODE
GAIN (dB)
HEADPHONE
MODE GAIN (dB)
0
0
6
3.5
0
1
10
3.5
1
0
15.6
3.5
1
1
21.6
3.5
______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
The MAX9789/MAX9790 feature control inputs for the
independent enabling of the speaker and headphone
amplifiers, allowing both to be active simultaneously if
required. Driving SPKR_EN high disables the speaker
amplifiers. Driving HP_EN low independently disables
the headphone amplifiers. For applications that require
only one of the amplifiers to be on at a given time,
SPKR_EN and HP_EN can be tied together allowing a
single logic voltage to enable either the speaker or the
headphone amplifier as shown in Figure 4.
MUTE
The MAX9789/MAX9790 allow for the speaker and
headphone amplifiers to be muted. By driving MUTE
low, both the speaker and headphone amplifiers are
muted. When muted, the speaker outputs remain
biased at VDD / 2.
Shutdown
The MAX9789/MAX9790 feature a low-power shutdown
mode, drawing 0.3µA of supply current. By disabling the
speaker, headphone amplifiers and the LDO (for
MAX9789), the MAX9789/MAX9790 enter low-power
shutdown mode. Set SPKR_EN to VDD and HP_EN and
LDO_EN to GND to disable the speaker amplifiers, headphone amplifiers, and LDO, respectively.
Click-and-Pop Suppression
Speaker Amplifier
The MAX9789/MAX9790 speaker amplifiers feature
Maxim’s comprehensive, industry-leading click-andpop suppression. During startup, the click-and-pop
suppression circuitry eliminates any audible transient
sources internal to the device. When entering shutdown, the differential speaker outputs ramp to GND
quickly and simultaneously.
Headphone Amplifier
In conventional single-supply headphone amplifiers, the
output-coupling capacitor is a major contributor of audible clicks and pops. Upon startup, the amplifier charges
the coupling capacitor to its bias voltage, typically
VDD / 2. Likewise, during shutdown, the capacitor is discharged to GND. A DC shift across the capacitor results,
which in turn, appears as an audible transient at the
headphone. Since the MAX9789/MAX9790 do not require
output-coupling capacitors, no audible transient occurs.
Additionally, the MAX9789/MAX9790 features extensive
click-and-pop suppression that eliminates any audible
transient sources internal to the device. The
startup/shutdown waveform in the Typical Operating
Characteristics shows that there are minimal spectral
components in the audible range at the output.
Applications Information
BTL Speaker Amplifiers
The MAX9789/MAX9790 feature speaker amplifiers
designed to drive a load differentially, a configuration
referred to as bridge-tied load (BTL). The BTL configuration (Figure 5) offers advantages over the singleended configuration, where one side of the load is
connected to ground. Driving the load differentially
doubles the output voltage compared to a singleended amplifier operating under similar conditions. The
doubling of the output voltage yields four times the output power at the load.
Since the differential outputs are biased at mid-supply,
there is no net DC voltage across the load. This eliminates the need for DC-blocking capacitors required for
single-ended amplifiers. These capacitors can be
large, expensive, consume board space, and degrade
low-frequency performance.
+1
VOUT(P-P)
MAX9789/MAX9790
SINGLE
CONTROL PIN
2 x VOUT(P-P)
SPKR_EN
HP_EN
-1
Figure 4. Enabling Either the Speaker or Headphone Amplifier
with a Single Control Pin
Figure 5. Bridge-Tied Load Configuration
VOUT(P-P)
______________________________________________________________________________________
17
MAX9789/MAX9790
Speaker and Headphone
Amplifier Enable
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
Mono Speaker Configuration
Output Power (Speaker Amplifier)
The MAX9789 stereo BTL Class AB speaker amplifier
can be configured to drive a mono speaker. Rather
than combining the CODEC’s left- and right-input signals in a resistive network prior to one channel of the
speaker amplifier input, the transducer itself can be
connected to the BTL speaker amplifier output as
shown in Figure 6. When compared to the resistive network implementation, the configuration in Figure 6 will:
1) Eliminate noise pickup by eliminating the highimpedance node at the CODEC’s left- and rightsignal mixing point. SNR performance will be
improved as a result.
2) Eliminate gain error by eliminating any resistive
mismatch between the external resistance used to
sum the left and right signals and the MAX9789
internal resistance.
The increase in power delivered by the BTL configuration directly results in an increase in internal power dissipation over the single-ended configuration. The
maximum power dissipation for a given VDD and load is
given by the following equation:
Power Dissipation and Heat Sinking
Under normal operating conditions, the MAX9789/
MAX9790 can dissipate a significant amount of power.
The maximum power dissipation for each package is
given in the Absolute Maximum Ratings section under
Continuous Power Dissipation, or can be calculated by
the following equation:
PDISSPKG(MAX) =
TJ(MAX) − TA
θJA
where TJ(MAX) is +150°C, TA is the ambient temperature, and θJA is the reciprocal of the derating factor in
°C/W as specified in the Absolute Maximum Ratings
section. For example, θJA for the 32-pin TQFN-EP package is +40.2°C/W for a multilayer PC board.
CODEC
CIN1
SPKR_OUTL
OUTL+
SPKR_INL
OUTL-
CIN1
SPKR_OUTR
OUTR+
LINE_OUTR
OUTRHP_INL
HPL
CIN2
LINE_OUTL
HP_INR
HPR
Figure 6. Mono Signal Output Configuration for MAX9789
18
2VDD2
π 2RL
If the power dissipation for a given application exceeds
the maximum allowed for a given package, either reduce
VDD, increase load impedance, decrease the ambient
temperature, or add heat sinking to the device. Large
output, supply, and ground PC board traces improve the
maximum power dissipation in the package.
Thermal-overload protection limits total power dissipation in these devices. When the junction temperature
exceeds +150°C, the thermal-protection circuitry disables the amplifier output stage. The amplifiers are
enabled once the junction temperature cools by +15°C.
This results in a pulsing output under continuous thermal-overload conditions as the device heats and cools.
Power Supplies
The MAX9789/MAX9790 have separate supply pins for
each portion of the device, allowing for the optimum
combination of headroom and power dissipation and
noise immunity. The speaker amplifiers are powered
from PVDD. PVDD ranges from 4.5V to 5.5V. The headphone amplifiers are powered from HPVDD and PVSS.
HPVDD is the positive supply of the headphone amplifiers and ranges from 3V to 5.5V. PVSS is the negative
supply of the headphone amplifiers. Connect PVSS to
CPV SS . The charge pump is powered by CPV DD .
CPVDD ranges from 3V to 5.5V and should be the same
potential as HPVDD. The charge pump inverts the voltage at CPVDD, and the resulting voltage appears at
CPV SS . The internal LDO and the remainder of the
device is powered by VDD.
Component Selection
MAX9789
SPKR_INR
CIN2
PDISS(MAX) =
Supply Bypassing
The MAX9789/MAX9790 have separate supply pins for
each portion of the device, allowing for the optimum
combination of headroom and power dissipation and
noise immunity.
Speaker Amplifier Power-Supply Input (PVDD)
The speaker amplifiers are powered from PVDD. PVDD
ranges from 4.5V to 5.5V. Bypass PVDD with a 0.1µF
capacitor to PGND. Note additional bulk capacitance is
required at the device if long input traces between
PVDD and the power source are used.
______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
Power Supply and LDO Input (VDD)
The internal LDO and the remainder of the device is
powered by V DD . V DD ranges from 4.5V to 5.5V.
Bypass VDD with a 0.1µF capacitor to GND and two
1µF capacitors in parallel to GND. Note additional bulk
capacitance is required at the device if long input
traces between VDD and the power source are used.
Input Filtering
The input capacitor (CIN), in conjunction with the amplifier input resistance (RIN), forms a highpass filter that
removes the DC bias from the incoming signal. The ACcoupling capacitor allows the amplifier to bias the signal to an optimum DC level. Assuming zero source
impedance, the -3dB point of the highpass filter is
given by:
f − 3dB =
1
2πRINCIN
RIN is the amplifier’s internal input resistance value
given in the Electrical Characteristics. Choose CIN such
that f-3dB is well below the lowest frequency of interest.
Setting f-3dB too high affects the amplifier’s low frequency response. Use capacitors with adequately low
voltage coefficient dielectrics, such as 1206-sized X7R
ceramic capacitors. Capacitors with higher voltage
coefficients result in increased distortion at low frequencies (see Figure 7).
INPUT COUPLING CAPACITOR-INDUCED THD+N
vs. FREQUENCY (HEADPHONE MODE)
-50
-55
0402 6.3V X5R 10% 1μF
-60
THD+N (dB FS)
The headphone amplifiers are powered from HPVDD
and PVSS. HPVDD is the positive supply of the headphone amplifiers and ranges from 3.0V to 5.5V. Bypass
HPVDD with a 10µF capacitor to PGND. PVSS is the
negative supply of the headphone amplifiers. Bypass
PVSS with a 1µF capacitor to PGND. Connect PVSS to
CPV SS . The charge pump is powered by CPV DD .
CPVDD ranges from 3.0V to 5.5V and should be the
same potential as HPVDD. Bypass CPVDD with a 1µF
capacitor to PGND. The charge pump inverts the voltage at CPVDD, and the resulting voltage appears at
CPVSS. A 1µF capacitor must be connected between
C1N and C1P.
MAX9789/MAX9790
Headphone Amplifier Power-Supply
Input (HPVDD and PVSS)
0603 10V X5R 10% 1μF
-65
-70
-75
-80
0805 25V X7R 10% 1μF
1206 25 X7R 10% 1μF
-85
-90
10
100
VOUT = -3dB FS
FS = 1VRMS
RL = 32Ω
1000
FREQUENCY (Hz)
Figure 7. Input Coupling Capacitor-Induced THD+N vs.
Frequency (Headphone Mode)
BIAS Capacitor
BIAS is the output of the internally generated DC bias
voltage. The BIAS bypass capacitor, CBIAS improves
PSRR and THD+N by reducing power supply and other
noise sources at the common-mode bias node, and
also generates the clickless/popless, startup/shutdown
DC bias waveforms for the speaker and headphone
amplifiers. Bypass BIAS with a 1µF capacitor to GND.
Charge-Pump Capacitor Selection
Use capacitors with an ESR less than 100mΩ for optimum performance. Low ESR ceramic capacitors minimize the output resistance of the charge pump. For
best performance over the extended temperature
range, select capacitors with an X7R dielectric.
Flying Capacitor (C1)
The value of the flying capacitor (C1) affects the load
regulation and output resistance of the charge pump. A
C1 value that is too small degrades the device’s ability
to provide sufficient current drive, which leads to a loss
of output voltage. Connect a 1µF capacitor between
C1P and C1N.
______________________________________________________________________________________
19
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
Output Capacitor (C2)
The output capacitor value and ESR directly affect the
ripple at CPVSS. Increasing the value of C2 reduces
output ripple. Likewise, decreasing the ESR of C2
reduces both ripple and output resistance. Lower
capacitance values can be used in systems with low
maximum output power levels.
CPVDD Bypass Capacitor (C3)
The CPVDD bypass capacitor (C3) lowers the output
impedance of the power supply and reduces the
impact of the MAX9789/MAX9790’s charge-pump
switching transients. Bypass CPVDD with 1µF, the same
value as C1, and place it physically close to the CPVDD
and CPGND pins.
Layout and Grounding
Proper layout and grounding are essential for optimum
performance. Use large traces for the power-supply
inputs and amplifier outputs to minimize losses due to
parasitic trace resistance, as well as route heat away
from the device. Good grounding improves audio performance, minimizes crosstalk between channels, and
prevents switching noise from coupling into the audio
signal. Connect PGND and GND together at a single
point on the PC board. Route PGND and all traces that
carry switching transients away from GND and the
traces and components in the audio signal path.
20
Connect C2 and C3 to the PGND plane. Connect PVSS
and CPVSS together at C2. Place the charge-pump
capacitors (C1, C2, and C3) as close as possible to
the device. Bypass PVDD with a 0.1µF capacitor to
PGND. Place the bypass capacitors as close as possible to the device.
Use large, low-resistance output traces. As load impedance decreases, the current drawn from the device outputs increase. At higher current, the resistance of the
output traces decrease the power delivered to the load.
For example, if 2W is delivered from the speaker output
to a 4Ω load through a 100mΩ trace, 49mW is consumed in the trace. If power is delivered through a
10mΩ trace, only 5mW is consumed in the trace. Large
output, supply and GND traces also improve the power
dissipation of the device.
The MAX9789/MAX9790 thin QFN package features an
exposed thermal pad on its underside. This pad lowers
the package’s thermal resistance by providing a direct
heat conduction path from the die to the printed circuit
board. Connect the exposed thermal pad to GND by
using a large pad and multiple vias to the GND plane.
______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
4.5V TO 5.5V
1.0µF
4.5V TO 5.5V
1.0µF
0.1µF
0.1µF
VDD
PVDD
8, 18
30
MAX9789
1.0µF
1.0µF
SPKR_INL
SPKR_INR
3
STEREO
BTL
AMPLIFIER
2
6
OUTL+
7
OUTL-
20
OUTR+
19
OUTR-
24
BIAS
TO HPVDD
1.0µF
1.0µF
3V TO 5.5V
HP_INL
27
HP_INR
26
HP_EN
22
MUTE
25
SPKR_EN
23
1.0µF
GAIN1
15
HPR
17
HPVDD
9
CPVDD
LDO_EN
31
LDO_OUT
1.0µF
1
LDO BLOCK
C1P
11
CPGND
12
C1N
C3
10µF
C1
1µF
29
28
GND
LOGIC PINS CONFIGURED FOR:
LDO_EN = 1, LDO ENABLED
SPKR_EN = 0, SPEAKER AMPLIFIERS ENABLED
HP_EN = 1, HEADPHONE AMPLIFIER ENABLED
MUTE = 1, MUTE DISABLED
GAIN1 = 0 GAIN = 0, 6dB SPEAKER GAIN
10
4
CHARGE
PUMP
LDO_SET
3V TO 5.5V
CONTROL
3V TO 5.5V
1.0µF
HPL
TO PVSS
GAIN2 32
TO CODEC
16
5, 21
PGND
14
13
PVSS
CPVSS
C2
1.0µF
______________________________________________________________________________________
21
MAX9789/MAX9790
Block Diagrams
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
MAX9789/MAX9790
Block Diagrams (continued)
4.5V TO 5.5V
0.1μF
0.1μF
VDD
30
PVDD
8, 18
MAX9790
1.0μF
1.0μF
SPKR_INL
SPKR_INR
3
STEREO
BTL
AMPLIFIER
2
6
OUTL+
7
OUTL-
20
OUTR+
19
OUTR-
24
BIAS
TO HPVDD
1.0μF
1.0μF
HP_INL
27
HP_INR
26
1.0μF
16
HPL
15
HPR
TO PVSS
3V TO 5.5V
HP_EN
22
MUTE
25
17
HPVDD
23
9
CPVDD
SPKR_EN
CONTROL
GAIN2 32
GAIN1
C1P
11
CPGND
12
C1N
31
CHARGE
PUMP
4, 28
GND
LOGIC PINS CONFIGURED FOR:
SPKR_EN = 0, SPEAKER AMPLIFIERS ENABLED
HP_EN = 1, HEADPHONE AMPLIFIER ENABLED
MUTE = 1, MUTE DISABLED
GAIN1 = 0 GAIN = 0, 6dB SPEAKER GAIN
22
10
5, 21
PGND
14
13
PVSS
CPVSS
3V TO 5.5V
C3
10μF
C1
1μF
C2
1.0μF
______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
5.0V
0.1μF
1μF
CBULK
1μF
BIAS VDD
VLDO_OUT
5.0V
10μF
PVDD
HPVDD
1μF
CIN
1μF
SPKR_L
SPKR_INR
CIN
1μF
OUTR+
4Ω
HP_INR
CIN
1μF
HP_L
OUTR-
HP_INL
HPL
5.0V
MONO
DGND
4Ω
OUTL-
SPKR_INL
CIN
1μF
SPKR_R
HDA
CODEC
HP_R
OUTL+
MAX9789
AGND
HPR
CPVDD
C3
1μF
C1
1μF
C1P
4.75V
LDO_SET
C1N
LDO_OUT
SPKR_EN
μC
1μF
1μF
HP_EN
LDO_EN
CPVSS
GAIN1
C2
1μF
PVSS
GAIN2
CPGND
MUTE
GND
PGND
12V
100μF
1μF
VDD
FS2
FS1
OUT+
G1
OUT-
8Ω
G2
SHDN
MAX9713
C1P
0.47μF
0.1μF
IN+
C1N
0.47μF
VDD
IN-
1μF
SS
CHOLD
REG
0.47μF
0.01μF
PGND
AGND
______________________________________________________________________________________
23
MAX9789/MAX9790
System Diagrams
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
MAX9789/MAX9790
System Diagrams (continued)
1μF
1μF
+5V
+3.3V
PVDD
HPVDD
10μF
0.1μF
VDD
VLDO_OUT
OUTL+
1μF
SPKR_L
OUTL-
SPKR_INL
1μF
SPKR_R
HDA
CODEC
HP1_R
SPKR_INR
OUTR+
1μF
HP_INR
OUTR-
1μF
HP_INL
HP1_L
HP1
HPL
+3.3V
MAX9789
HP2_R
HPR
CPVDD
HP2_L
C3
1μF
DGND AGND
C1
1μF
C1P
4.75V
LDO_SET
C1N
SPKR_EN
LDO_OUT
1μF
HP_EN
μC
1μF
LDO_EN
CPVSS
GAIN2
MUTE
C2
1μF
PVSS
GAIN1
CPGND
PGND
GND
C1P
SHDNR
1μF
SHDNL
C1N
1μF
MAX4411
HP2
OUTL
INR
1μF
OUTR
INL
+3.3V
PVDD
1μF
PVSS
SVSS
SVDD
SGND
24
PGND
1μF
______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
BIAS
SPKR_EN
HP_EN
PGND
OUTR+
OUTR-
PVDD
HPVDD
BIAS
SPKR_EN
HP_EN
PGND
OUTR+
OUTR-
PVDD
HPVDD
TOP VIEW
24
23
22
21
20
19
18
17
24
23
22
21
20
19
18
17
MUTE 25
16
HPL
MUTE 25
16
HPL
HP_INR 26
15
HPR
HP_INR 26
15
HPR
HP_INL 27
14
PVSS
HP_INL 27
14
PVSS
13
13
CPVSS
12
C1N
11
CPGND
10
9
6
7
8
PVDD
SPKR_INL
5
OUTL-
SPKR_INR
4
OUTL+
3
PGND
2
LDO_EN
1
LDO_SET
GAIN2 32
C1P
GAIN1 31
CPVDD
GAIN2 32
EP*
+
1
2
3
4
5
6
7
8
PVDD
VDD 30
OUTL-
CPGND
OUTL+
11
MAX9790
PGND
EP*
+
C1N
N.C. 29
GND
GAIN1 31
GND 28
SPKR_INL
VDD 30
CPVSS
12
SPKR_INR
MAX9789
LDO_OUT 29
N.C.
GND 28
C1P
9
CPVDD
TQFN
TQFN
*EP = EXPOSED PADDLE
*EP = EXPOSED PADDLE
Simplified Block Diagrams
(continued)
SPEAKER SUPPLY
4.5V TO 5.5V
10
Chip Information
PROCESS: BiCMOS
HEADPHONE SUPPLY
3.0V TO 5.5V
MAX9790
SPKR_INR
SPKR_INL
HP_INR
HP_INL
SPKR_EN
HP_EN
MUTE
GAIN1
GAIN2
______________________________________________________________________________________
25
MAX9789/MAX9790
Pin Configurations
Package Information
For the latest package outline information and land patterns, 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
DOCUMENT NO.
32 TQFN-EP
T3255N-1
21-0140
QFN THIN.EPS
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
26
______________________________________________________________________________________
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
______________________________________________________________________________________
27
MAX9789/MAX9790
Package Information (continued)
For the latest package outline information and land patterns, 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.
MAX9789/MAX9790
Windows Vista-Compliant, Stereo Class AB Speaker
Amplifiers and DirectDrive Headphone Amplifiers
Revision History
REVISION
NUMBER
REVISION
DATE
2
8/08
Added MAX9789C to data sheet and made miscellaneous clarifications
3
9/09
Corrected the Block Diagrams
DESCRIPTION
PAGES
CHANGED
1–11, 13, 14, 18
21
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.
28 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2009 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
工商网监
湘ICP备2023018690号
