19-3050; Rev 7; 4/10
KIT
ATION
EVALU
BLE
AVAILA
Low-Cost, Mono/Stereo,
1.4W Differential Audio Power Amplifiers
General Description
Features
o
2.7V to 5.5V Single-Supply Operation
o
Very High -93dB PSRR at 217Hz
o
1.4W into 4Ω at 1% THD+N (per Channel)
o
Differential Input
o
Internal Fixed Gain to Reduce Component Count
o
Adjustable Gain Option (MAX9718A/H/MAX9719A)
o
100nA Low-Power Shutdown Mode
o
No Audible Clicks or Pops at Power-Up/Down
o
Improved Performance Pin-Compatible Upgrade
to LM4895 (MAX9718D/G)
o
1.8V Logic Compatible
MAX9718/MAX9719
The MAX9718/MAX9719 differential input audio power
amplifiers are ideal for portable audio devices with
internal speakers. The differential input structure
improves noise rejection and provides common-mode
rejection. A bridge-tied load (BTL) architecture mini-
mizes external component count, while providing high-
quality, power audio amplification. The MAX9718 is a
single-channel amplifier while the MAX9719 is a dual-
channel amplifier for stereo systems. Both devices
deliver 1.4W continuous average power per channel to
a 4Ω load with less than 1% THD+N while operating
from a single +5V supply. The devices are available as
adjustable gain amplifiers or with internally fixed gains
of 0dB, 3dB, and 6dB to reduce component count.
A shutdown input disables the bias generator and
amplifiers and reduces quiescent current consumption
to less than 100nA. The MAX9718 shutdown input can
be set as active high or active low. These devices fea-
ture Maxim’s comprehensive click-and-pop suppres-
sion circuitry that reduces audible clicks and pops
during startup and shutdown.
The MAX9718 is pin compatible with the LM4895,
and is available in 9-bump UCSP™, 10-pin TDFN, and
10-pin μMAX
®
packages. The MAX9719 is available in
16-pin TQFN, 16-pin TSSOP, and 16-bump UCSP pack-
ages. Both devices operate over the -40°C to +85°C
extended temperature range.
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
TOP
MARK
+ADX
+AAV
MAX9718
AEBL+TG45 -40°C to +85°C 3 x 3 UCSP
MAX9718AETB+T
-40°C to +85°C 10 TDFN-EP*
+Denotes
lead(Pb)-free/RoHS-compliant package.
*EP
= Exposed pad.
G45 indicates protective die coating.
Ordering Information continued at end of data sheet.
Pin Configurations appear at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
μMAX is a registered trademark of Maxim Integrated Products, Inc.
Applications
Mobile Phones
PDAs
Portable Devices
Simplified Block Diagrams
SINGLE SUPPLY
2.7V TO 5.5V
SINGLE SUPPLY
2.7V TO 5.5V
INL+
IN+
OUT+
INL-
INR+
OUTL-
OUTR+
OUTL+
IN-
SHDN
OUT-
INR-
SHDM
MAX9718
SHDN
OUTR-
MAX9719
________________________________________________________________
Maxim Integrated Products
1
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.
Low-Cost, Mono/Stereo,
1.4W Differential Audio Power Amplifiers
MAX9718/MAX9719
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (V
CC
to GND) ..................................-0.3V to +6V
Any Other Pin to GND ...............................-0.3V to (V
CC
+ 0.3V)
IN_, BIAS, SHDM, SHDN,
SHDN
Continuous Current ........20mA
OUT_ Short-Circuit Duration to GND or V
CC
.............Continuous
Continuous Power Dissipation (T
A
= +70°C)
9-Bump UCSP (derate 5.2mW/°C above +70°C) .......1067mW
10-Pin TDFN (derate 24.4mW/°C above +70°C) ........1951mW
10-Pin μMAX (derate 10.3mW/°C above +70°C) ..........825mW
16-Bump UCSP (derate 8.2mW/°C above +70°C) .....1633mW
16-Pin TQFN (derate 16.9mW/°C above +70°C) ........1349mW
16-Pin TSSOP (derate 21.3mW/°C above +70°C) ......1702mW
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
Soldering Temperature (reflow) .......................................+260°C
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—5V Supply
(V
CC
= 5V, GND = 0, SHDN/SHDN = V
CC
(MAX9718/MAX9719), SHDM = GND (MAX9718), R
IN
= R
F
= 10kΩ (MAX971_A/H),
T
A
= +25°C. C
BIAS
= 0.1μF, no load. Typical values are at T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Supply Voltage
Supply Current
Shutdown Supply Current
SHDN,
SHDN, SHDM
Threshold
SHDN,
SHDN, SHDM
Threshold
SYMBOL
V
CC
I
CC
I
SHDN
V
IH
V
IL
V
IH
V
IL
V
IN-
= V
IN+
= V
BIAS
, T
A
= -40°C to +85°C,
per amplifier (Note 2)
SHDN = SHDM =
SHDN
= GND, per amplifier
MAX9718A/B/C/D
MAX9718E/F/G/H
A
V
= 0dB, MAX971_A/H,
MAX971_B/E
Output Offset Voltage
V
OS
V
IN-
= V
IN+
= V
BIAS
A
V
= 3dB, MAX971_C/F
A
V
= 6dB, MAX971_D/G
Inferred from
CMRR test
A
V
= 0dB, MAX971_B/E
A
V
= 3dB, MAX971_C/F
A
V
= 6dB, MAX971_D/G
External gain, MAX971_A/H
Input Impedance
Common-Mode Rejection Ratio
R
IN
CMRR
MAX971_B/E, MAX971_C/F, MAX971_D/G
f
N
= 1kHz
V
IN-
= V
IN+
= V
BIAS
,
V
RIPPLE
= 200mV
P-P
,
R
L
= 8Ω, C
BIAS
= 1μF
THD+N = 1%,
f
IN
= 1kHz (Note 4)
f = 217Hz
f = 1kHz
R
L
= 8Ω
R
L
= 4Ω
0.8
0.5
0.5
0.5
0.5
10
-50
15
-60
-60
-93
dB
-90
1.1
1.4
0.002
W
%
0.7 x V
CC
0.3 x V
CC
1.4
0.4
±1
±1
±1
±10
±15
±20
V
CC
- 0.5
V
CC
- 0.6
V
CC
- 0.8
V
CC
- 1.2
20
kΩ
dB
V
mV
CONDITIONS
MIN
2.7
5.0
0.1
TYP
MAX
5.5
7.5
1
UNITS
V
mA
μA
V
V
Common-Mode Input Voltage
V
IC
Power-Supply Rejection Ratio
PSRR
Output Power
Total Harmonic Distortion Plus
Noise
P
OUT
THD+N
R
L
= 8Ω, f
IN
= 1kHz, P
OUT
= 0.75W,
V
CC
= 5V, A
V
= 6dB (Note 5)
2
_______________________________________________________________________________________
Low-Cost, Mono/Stereo,
1.4W Differential Audio Power Amplifiers
ELECTRICAL CHARACTERISTICS—5V Supply (continued)
(V
CC
= 5V, GND = 0, SHDN/SHDN = V
CC
(MAX9718/MAX9719), SHDM = GND (MAX9718), R
IN
= R
F
= 10kΩ (MAX971_A/H),
T
A
= +25°C. C
BIAS
= 0.1μF, no load. Typical values are at T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Gain Accuracy
Channel-to-Channel Gain
Matching
Signal-to-Noise Ratio
Thermal-Shutdown Threshold
Thermal-Shutdown Hysteresis
Maximum Capacitive Drive
Power-Up/Enable from
Shutdown Time
Shutdown Time
Turn-Off Transient
Crosstalk
C
LOAD
t
PU
t
SHDN
V
POP
(Note 6)
MAX9719, f
IN
= 1kHz
Bridge-tied capacitance
SNR
SYMBOL
CONDITIONS
MAX971_B/E, MAX971_C/F, MAX971_D/G
MAX9719B/E, MAX9719C/F, MAX9719D/G
P
OUT
= 1W, R
L
= 8Ω
-104
+160
15
500
10
3.5
50
-85
MIN
TYP
MAX
±1
±1
UNITS
%
%
dB
°C
°C
pF
ms
μs
mV
dB
MAX9718/MAX9719
ELECTRICAL CHARACTERISTICS—3V Supply
(V
CC
= 3V, GND = 0, SHDN/SHDN = V
CC
(MAX9718/MAX9719), SHDM = GND (MAX9718), R
IN
= R
F
= 10kΩ (MAX971_A/H),
T
A
= +25°C. C
BIAS
= 0.1μF, no load. Typical values are at T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Supply Current
Shutdown Supply Current
SHDN,
SHDN, SHDM
Threshold
Common-Mode Bias Voltage
SYMBOL
I
CC
I
SHDN
V
IH
V
IL
V
BIAS
(Note 3)
A
V
= 0dB, MAX971_A/H
MAX971_B/E
Output Offset Voltage
V
OS
V
IN-
= V
IN+
= V
BIAS
A
V
= 3dB, MAX971_C/F
A
V
= 6dB, MAX971_D/G
Inferred from
CMRR test
A
V
= 0dB, MAX971_B/E
A
V
= 3dB, MAX971_C/F
A
V
= 6dB, MAX971_D/G
External gain, MAX971_A/H
Input Impedance
Common-Mode Rejection Ratio
R
IN
CMRR
MAX971_B/E, MAX971_C/F, MAX971_D/G
f
N
= 1kHz
V
IN-
= V
IN+
= V
BIAS
,
V
RIPPLE
= 200mV
P-P
,
R
L
= 8Ω,
C
BIAS
= 1μF
f = 217Hz
f = 1kHz
0.5
0.5
0.5
0.5
10
-50
15
-60
-70
-93
dB
-90
V
CC
/2
- 5%
V
CC
/2
±1
±1
±1
CONDITIONS
V
IN-
= V
IN+
= V
BIAS
, T
A
= -40°C to +85°C,
per amplifier (Note 2)
SHDN = SHDM =
SHDN
= GND, per amplifier
0.7 x V
CC
0.3 x V
CC
V
CC
/2
+ 5%
±10
±15
±20
V
CC
- 0.7
V
CC
- 0.8
V
CC
- 1.0
V
CC
- 1.2
20
kΩ
dB
V
mV
MIN
TYP
3.8
0.1
MAX
6.0
1
UNITS
mA
μA
V
V
Common-Mode Input Voltage
V
IC
Power-Supply Rejection Ratio
PSRR
_______________________________________________________________________________________
3
Low-Cost, Mono/Stereo,
1.4W Differential Audio Power Amplifiers
MAX9718/MAX9719
ELECTRICAL CHARACTERISTICS—3V Supply (continued)
(V
CC
= 3V, GND = 0, SHDN/SHDN = V
CC
(MAX9718/MAX9719), SHDM = GND (MAX9718), R
IN
= R
F
= 10kΩ (MAX971_A/H),
T
A
= +25°C. C
BIAS
= 0.1μF, no load. Typical values are at T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Output Power
Total Harmonic Distortion Plus
Noise
Thermal-Shutdown Threshold
Thermal-Shutdown Hysteresis
Maximum Capacitive Drive
Power-Up/Enable from
Shutdown Time
Shutdown Time
Turn-Off Transient
Crosstalk
C
LOAD
t
PU
t
SHDN
V
POP
(Note 6)
MAX9719, f
IN
= 1kHz
Bridge-tied capacitance
SYMBOL
P
OUT
THD+N
CONDITIONS
R
L
= 8Ω, THD+N = 1%, f
IN
= 1kHz (Note 4)
R
L
= 8Ω, f
IN
= 1kHz, P
OUT
= 0.25W,
A
V
= 6dB
MIN
TYP
475
0.003
+160
15
500
10
3
40
-85
MAX
UNITS
mW
%
°C
°C
pF
ms
μs
mV
dB
Note 1:
All specifications are 100% tested at T
A
= +25°C. Specifications over temperature (T
A
= T
MIN
to T
MAX
) are guaranteed by
design, not production tested.
Note 2:
Quiescent power-supply current is specified and tested with no load. Quiescent power-supply current depends on the offset
voltage when a practical load is connected to the amplifier. Guaranteed by design.
Note 3:
Common-mode bias voltage is the voltage on BIAS and is nominally V
CC
/2.
Note 4:
Output power is specified by a combination of a functional output current test and characterization analysis.
Note 5:
Measurement bandwidth for THD+N is 22Hz to 22kHz.
Note 6:
Peak voltage measured at power-on, power-off, into or out of SHDN. Bandwidth defined by A-weighted filters, inputs at AC
GND. V
CC
rise and fall times greater than or equal to 1ms.
Typical Operating Characteristics
(V
CC
= 5V, C
BIAS
= 0.1μF, THD+N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX9718 toc01
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX9718 toc02
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
V
CC
= 5V
R
L
= 8Ω
A
V
= 2
MAX9718 toc03
10
V
CC
= 5V
R
L
= 4Ω
A
V
= 2
10
V
CC
= 5V
R
L
= 4Ω
A
V
= 4
OUTPUT POWER = 1W
10
1
1
1
THD+N (%)
0.1
THD+N (%)
THD+N (%)
OUTPUT POWER = 1W
0.1
0.1
OUTPUT POWER = 750mW
0.01
0.01
OUTPUT POWER = 50mW
0.001
0.01
OUTPUT POWER = 200mW
0.001
0.001
OUTPUT POWER = 250mW
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
4
_______________________________________________________________________________________
Low-Cost, Mono/Stereo,
1.4W Differential Audio Power Amplifiers
Typical Operating Characteristics (continued)
(V
CC
= 5V, C
BIAS
= 0.1μF, THD+N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX9718 toc05
MAX9718/MAX9719
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX9718 toc04
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
V
CC
= 3V
R
L
= 4Ω
A
V
= 4
OUTPUT POWER = 175mW
MAX9718 toc06
10
V
CC
= 5V
R
L
= 8Ω
A
V
= 4
10
V
CC
= 3V
R
L
= 4Ω
A
V
= 2
10
1
1
1
THD+N (%)
THD+N (%)
THD+N (%)
0.1
OUTPUT POWER = 800mW
0.1
OUTPUT POWER = 50mW
0.1
0.01
OUTPUT POWER = 200mW
0.01
OUTPUT POWER = 250mW
0.01
OUTPUT POWER = 70mW
0.001
0.001
0.001
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX9718 toc07
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX9718 toc08
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER
V
CC
= 5V
R
L
= 4Ω
A
V
= 2
MAX9718 toc09
10
V
CC
= 3V
R
L
= 8Ω
A
V
= 2
10
V
CC
= 3V
R
L
= 8Ω
A
V
= 4
100
1
1
10
THD+N (%)
THD+N (%)
THD+N (%)
0.1
OUTPUT POWER = 100mW
0.01
0.1
OUTPUT POWER = 50mW
1
f
IN
= 10kHz
0.1
f
IN
= 100Hz
0.01
OUTPUT POWER = 200mW
0.001
OUTPUT POWER = 250mW
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
0.001
0.01
f
IN
= 1kHz
0.0001
10
100
1k
FREQUENCY (Hz)
10k
100k
0.001
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
OUTPUT POWER (W)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER
MAX9718 toc10
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER
MAX9718 toc11
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT POWER
V
CC
= 5V
R
L
= 8Ω
A
V
= 4
MAX9718 toc12
100
V
CC
= 5V
R
L
= 4Ω
A
V
= 4
100
V
CC
= 5V
R
L
= 8Ω
A
V
= 2
100
10
10
10
THD+N (%)
THD+N (%)
THD+N (%)
1
f
IN
= 100Hz
0.1
f
IN
= 10kHz
1
f
IN
= 1kHz
1
f
IN
= 100Hz
f
IN
= 1kHz
f
IN
= 10kHz
0.1
f
IN
= 100Hz
f
IN
= 10kHz
0.1
0.01
f
IN
= 1kHz
0.01
0.01
0.001
0
0.5
1.0
OUTPUT POWER (W)
1.5
2.0
0.001
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
OUTPUT POWER (W)
0.001
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
OUTPUT POWER (W)
_______________________________________________________________________________________
5