General Description
The MAX4410 stereo headphone driver is designed for
portable equipment where board space is at a
premium. The MAX4410 uses a unique, patented,
DirectDrive architecture to produce a ground-referenced output from a single supply, eliminating the need
for large DC-blocking capacitors, saving cost, board
space, and component height.
The MAX4410 delivers up to 80mW per channel into a
16Ω load and has low 0.003% THD + N. A high powersupply rejection ratio (90dB at 1kHz) allows this device to
operate from noisy digital supplies without an additional
linear regulator. The MAX4410 includes ±8kV ESD protection on the headphone outputs. Comprehensive clickand-pop circuitry suppresses audible clicks and pops on
startup and shutdown. Independent left/right, low-power
shutdown controls make it possible to optimize power
savings in mixed mode, mono/stereo applications.
The MAX4410 operates from a single 1.8V to 3.6V supply,
consumes only 7mA of supply current, has short-circuit
and thermal overload protection, and is specified over the
extended -40°C to +85°C temperature range. The
MAX4410 is available in a tiny (2mm x 2mm x 0.6mm),
16-bump chip-scale package (UCSP™) and a 14-pin
TSSOP package.
Applications
Features
♦ No Bulky DC-Blocking Capacitors Required
♦ Ground-Referenced Outputs Eliminate DC-Bias
Voltages on Headphone Ground Pin
♦ No Degradation of Low-Frequency Response Due
to Output Capacitors
♦ 80mW Per Channel into 16Ω
♦ Low 0.003% THD + N
♦ High PSRR (90dB at 1kHz)
♦ Integrated Click-and-Pop Suppression
♦ 1.8V to 3.6V Single-Supply Operation
♦ Low Quiescent Current
♦ Independent Left/Right, Low-Power
Shutdown Controls
♦ Short-Circuit and Thermal Overload Protection
♦ ±8kV ESD-Protected Amplifier Outputs
♦ Available in Space-Saving Packages
16-Bump UCSP (2mm x 2mm x 0.6mm)
14-Pin TSSOP
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
________________________________________________________________ Maxim Integrated Products 1
Functional Diagram
Ordering Information
19-2386; Rev 2; 10/02
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Notebooks
Cellular Phones
PDAs
MP3 Players
Web Pads
Portable Audio Equipment
*Future product—contact factory for availability.
UCSP is a trademark of Maxim Integrated Products, Inc.
Pin Configurations and Typical Application Circuit appear
at end of data sheet.
PART TEMP RANGE
MAX4410EBE-T* -40°C to +85°C 16 UCSP-16
MAX4410EUD -40°C to +85°C 14 TSSOP
PIN/BUMPPACKAGE
LEFT
AUDIO
INPUT
SHDNL
SHDNR
RIGHT
AUDIO
INPUT
MAX4410
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(PVDD= SVDD= 3V, PGND = SGND = 0, SHDNL = SHDNR = SVDD, C1 = C2 = 2.2µF, RIN= RF= 10kΩ, RL= ∞, TA= T
MIN
to T
MAX
,
unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 2)
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.
PGND to SGND .....................................................-0.3V to +0.3V
PV
DD
to SV
DD .................................................................
-0.3V to +0.3V
PV
SS
to SVSS.........................................................-0.3V to +0.3V
PV
DD
and SVDDto PGND or SGND .........................-0.3V to +4V
PV
SS
and SVSSto PGND or SGND ..........................-4V to +0.3V
IN_ to SGND ..........................................................-0.3V to +0.3V
SHDN_ to SGND........................(SGND - 0.3V) to (SV
DD
+ 0.3V)
OUT_ to SGND ............................(SV
SS
- 0.3V) to (SVDD+ 0.3V)
C1P to PGND.............................(PGND - 0.3V) to (PV
DD
+ 0.3V)
C1N to PGND .............................(PV
SS
- 0.3V) to (PGND + 0.3V)
Output Short Circuit to GND or V
DD
...........................Continuous
Continuous Power Dissipation (T
A
= +70°C)
14-Pin TSSOP (derate 9.1mW/°C above +70°C) ..........727mW
16-Bump UCSP (derate 15.2mW/°C above +70°C)....1212mW
Junction Temperature......................................................+150°C
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Bump Temperature (soldering) (Note 1)
Infrared (15s) ...............................................................+220°C
Vapor Phase (60s) .......................................................+215°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1: This device is constructed using a unique set of packaging techniques that impose a limit on the thermal profile the device
can be exposed to during board-level solder attach and rework. This limit permits only the use of the solder profiles recommended in the industry-standard specification, JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and convection reflow.
Preheating is required. Hand or wave soldering is not allowed.
Supply Voltage Range V
Quiescent Supply Current I
Shutdown Supply Current I
SHDN_ Thresholds
SHDN_ Input Leakage Current -1 +1 µA
SHDN_ to Full Operation t
CHARGE PUMP
Oscillator Frequency f
AMPLIFIERS
Input Offset Voltage V
Input Bias Current I
Power-Supply Rejection Ratio PSRR
Output Power P
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
SHDN
SON
OSC
BIAS
DD
DD
OS
OUT
Guaranteed by PSRR test 1.8 3.6 V
One channel enabled 4
Two channels enabled 7 11.5
SHDNL = SHDNR = GND 6 10 µA
V
V
Input AC-coupled, RL = 32Ω 0.5 2.4 mV
1.8V ≤ VDD ≤ 3.6V DC 75 90
200mV
THD + N = 1%
IH
IL
ripple
P-P
0.7 x
SV
DD
0.3 x
SV
DD
175 µs
272 320 368 kHz
-100 +100 nA
f
= 1kHz 90
RIPPLE
f
= 20kHz 55
RIPPLE
RL = 32Ω 65
R
= 16Ω 40 80
L
mA
V
dB
mW
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(PVDD= SVDD= 3V, PGND = SGND = 0, SHDNL = SHDNR = SVDD, C1 = C2 = 2.2µF, RIN= RF= 10kΩ, RL= ∞, TA= T
MIN
to T
MAX
,
unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 2)
Note 2: All specifications are 100% tested at T
A
= +25°C; temperature limits are guaranteed by design.
Typical Operating Characteristics
(
C1 = C2 = 2.2µF, THD + N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.
)
10 100 10k1k 100k
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
MAX4410 toc01
FREQUENCY (Hz)
THD + N (%)
1
0.1
0.001
0.01
VDD = 3V
A
V
= -1V/V
R
L
= 16Ω
P
OUT
= 10mW
P
OUT
= 25mW
P
OUT
= 50mW
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
MAX4410 toc02
THD + N (%)
1
0.1
0.001
0.01
VDD = 3V
A
V
= -2V/V
R
L
= 16Ω
P
OUT
= 25mW
P
OUT
= 10mW
P
OUT
= 50mW
10 100 10k1k 100k
FREQUENCY (Hz)
1
0.0001
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
0.001
0.01
0.1
MAX4410 toc03
VDD = 3V
A
V
= -1V/V
R
L
= 32Ω
P
OUT
= 5mW
P
OUT
= 10mW
P
OUT
= 25mW
THD + N (%)
10 100 10k1k 100k
FREQUENCY (Hz)
Total Harmonic Distortion Plus
Noise
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
THD + N f
Signal-to-Noise Ratio SNR RL = 32Ω, P
= 1kHz
IN
RL = 32Ω,
P
= 25mW
OUT
R
= 16Ω,
L
P
= 50mW
OUT
= 20mW, fIN = 1kHz 95 dB
OUT
0.003
0.003
Slew Rate SR 0.8 V/µs
Maximum Capacitive Load C
Crosstalk RL = 16Ω, P
No sustained oscillations 300 pF
L
= 1.6mW, fIN = 10kHz 70 dB
OUT
Thermal Shutdown Threshold 140 °C
Thermal Shutdown Hysteresis 15 °C
ESD Protection Human body model (OUTR, OUTL) ±8 kV
%
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
4 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(C1 = C2 = 2.2µF, THD + N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
1
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
0.001
0.01
0.1
MAX4410 toc04
THD + N (%)
10 100 10k1k 100k
FREQUENCY (Hz)
P
OUT
= 5mW
P
OUT
= 10mW
P
OUT
= 25mW
VDD = 3V
A
V
= -2V/V
R
L
= 32Ω
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
MAX4410 toc05
THD + N (%)
1
0.1
0.001
0.01
VDD = 1.8V
A
V
= -1V/V
R
L
= 16Ω
P
OUT
= 10mW
P
OUT
= 20mW
P
OUT
= 5mW
10 100 10k1k 100k
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
MAX4410 toc06
THD + N (%)
1
0.1
0.001
0.01
VDD = 1.8V
A
V
= -2V/V
R
L
= 16Ω
P
OUT
= 10mW
P
OUT
= 5mW
P
OUT
= 20mW
10 100 10k1k 100k
FREQUENCY (Hz)
1
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
0.001
0.01
0.1
MAX4410 toc07
VDD = 1.8V
A
V
= -1V/V
R
L
= 32Ω
P
OUT
= 20mW
THD + N (%)
P
OUT
= 10mW
P
OUT
= 5mW
10 100 10k1k 100k
FREQUENCY (Hz)
1
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. FREQUENCY
0.001
0.01
0.1
MAX4410 toc08
VDD = 1.8V
A
V
= -2V/V
R
L
= 32Ω
P
OUT
= 5mW
P
OUT
= 20mW
THD + N (%)
P
OUT
= 10mW
10 100 10k1k 100k
FREQUENCY (Hz)
100
10
1
0.1
0.01
0.001
0 100 15050 200
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc09
OUTPUT POWER (mW)
VDD = 3V
A
V
= -1V/V
R
L
= 16Ω
f
IN
= 20Hz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
0 100 15050 200
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc10
OUTPUT POWER (mW)
VDD = 3V
A
V
= -1V/V
R
L
= 16Ω
f
IN
= 1kHz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
0 100 15050 200
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc11
OUTPUT POWER (mW)
VDD = 3V
A
V
= -1V/V
R
L
= 16Ω
f
IN
= 10kHz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
0 100 15050 200
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc12
OUTPUT POWER (mW)
VDD = 3V
A
V
= -2V/V
R
L
= 16Ω
f
IN
= 20Hz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
_______________________________________________________________________________________ 5
Typical Operating Characteristics (continued)
(C1 = C2 = 2.2µF, THD + N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
VDD = 3V
= -2V/V
A
V
= 16Ω
R
L
10
= 1kHz
f
IN
1
OUTPUTS IN
PHASE
0.1
THD + N (%)
0.01
0.001
0 100 15050 200
OUTPUT POWER (mW)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
10
1
0.1
THD + N (%)
0.01
VDD = 3V
A
V
R
L
f
IN
= -1V/V
= 32Ω
= 1kHz
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
MAX4410 toc13
MAX4410 toc16
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
VDD = 3V
= -2V/V
A
V
= 16Ω
R
L
10
= 10kHz
f
IN
1
OUTPUTS IN
PHASE
0.1
THD + N (%)
0.01
0.001
0 100 15050 200
OUTPUT POWER (mW)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
VDD = 3V
A
R
10
f
1
0.1
THD + N (%)
0.01
= -1V/V
V
= 32Ω
L
= 10kHz
IN
ONE
CHANNEL
OUTPUTS IN
PHASE
TOTAL HARMONIC DISTORTION PLUS
100
VDD = 3V
A
V
10
OUTPUTS
180° OUT OF
PHASE
ONE
CHANNEL
MAX4410 toc14
R
L
f
IN
1
0.1
THD + N (%)
0.01
0.001
0.0001
0507525 125100
TOTAL HARMONIC DISTORTION PLUS
100
VDD = 3V
A
V
10
1
0.1
THD + N (%)
0.01
R
L
f
IN
OUTPUTS
180° OUT OF
PHASE
MAX4410 toc17
NOISE vs. OUTPUT POWER
OUTPUTS IN
PHASE
= -1V/V
= 32Ω
= 20Hz
ONE
CHANNEL
OUTPUT POWER (mW)
NOISE vs. OUTPUT POWER
ONE
CHANNEL
OUTPUTS IN
PHASE
= -1V/V
= 32Ω
= 20Hz
OUTPUTS
180° OUT OF
PHASE
OUTPUTS
180° OUT OF
PHASE
MAX4410 toc15
MAX4410 toc18
0.001
0 50 1007525 125
OUTPUT POWER (mW)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
VDD = 3V
= -2V/V
A
V
= 32Ω
R
L
10
= 1kHz
f
IN
1
0.1
THD + N (%)
0.01
0.001
0 50 1007525 125
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUT POWER (mW)
OUTPUTS
180° OUT OF
PHASE
MAX4410 toc19
0.001
0 50 1007525 125
OUTPUT POWER (mW)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
VDD = 3V
= -2V/V
A
V
= 32Ω
R
L
10
= 10kHz
f
IN
1
0.1
THD + N (%)
0.01
0.001
0 50 1007525 125
OUTPUTS IN
PHASE
OUTPUTS
180° OUT OF
PHASE
OUTPUT POWER (mW)
ONE
CHANNEL
MAX4410 toc20
0.001
0 50 1007525 125
OUTPUT POWER (mW)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
VDD = 1.8V
= -1V/V
A
V
= 16Ω
R
L
10
= 20Hz
f
IN
1
0.1
THD + N (%)
0.01
0.001
02040503010 60
OUTPUTS IN
PHASE
OUTPUTS
180° OUT OF
PHASE
ONE
CHANNEL
OUTPUT POWER (mW)
MAX4410 toc21
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
6 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(C1 = C2 = 2.2µF, THD + N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
100
10
1
0.1
0.01
0.001
02040503010 60
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc22
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -1V/V
R
L
= 16Ω
f
IN
= 1kHz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
02040503010 60
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc23
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -1V/V
R
L
= 16Ω
f
IN
= 10kHz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
02040503010 60
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc24
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -2V/V
R
L
= 16Ω
f
IN
= 20Hz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
02040503010 60
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc25
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -2V/V
R
L
= 16Ω
f
IN
= 1kHz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
02040503010 60
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc26
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -2V/V
R
L
= 16Ω
f
IN
= 10kHz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
02040503010
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc27
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -1V/V
R
L
= 32Ω
f
IN
= 20Hz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
02040503010
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc28
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -1V/V
R
L
= 32Ω
f
IN
= 1kHz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
02040503010
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc29
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -1V/V
R
L
= 32Ω
f
IN
= 10kHz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
100
10
1
0.1
0.01
0.001
02040503010
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
MAX4410 toc30
OUTPUT POWER (mW)
VDD = 1.8V
A
V
= -2V/V
R
L
= 32Ω
f
IN
= 20Hz
THD + N (%)
OUTPUTS IN
PHASE
ONE
CHANNEL
OUTPUTS
180° OUT OF
PHASE
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
_______________________________________________________________________________________ 7
Typical Operating Characteristics (continued)
(C1 = C2 = 2.2µF, THD + N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
VDD = 1.8V
= -2V/V
A
V
= 32Ω
R
L
10
= 1kHz
f
IN
1
OUTPUTS IN
PHASE
0.1
THD + N (%)
0.01
0.001
02040503010
OUTPUT POWER (mW)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
0
VDD = 1.8V
= 16Ω
R
L
-20
-40
OUTPUTS
180° OUT OF
PHASE
ONE
CHANNEL
MAX4410 toc31
MAX4410 toc34
TOTAL HARMONIC DISTORTION PLUS
NOISE vs. OUTPUT POWER
100
VDD = 1.8V
= -2V/V
A
V
= 32Ω
R
L
10
= 10kHz
f
IN
OUTPUTS IN
1
PHASE
0.1
THD + N (%)
0.01
0.001
02040503010
OUTPUT POWER (mW)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
0
VDD = 3V
= 32Ω
R
L
-20
-40
POWER-SUPPLY REJECTION RATIO
0
VDD = 3V
R
-20
-40
PSRR (dB)
-60
-80
-100
0.01 0.1 101 100
OUTPUTS
180° OUT OF
PHASE
ONE
CHANNEL
MAX4410 toc32
POWER-SUPPLY REJECTION RATIO
0
VDD = 1.8V
MAX4410 toc35
R
-20
-40
= 16Ω
L
= 32Ω
L
vs. FREQUENCY
MAX4410 toc33
FREQUENCY (kHz)
vs. FREQUENCY
MAX4410 toc36
PSRR (dB)
-60
-80
-100
0.01 0.1 101 100
FREQUENCY (kHz)
CROSSTALK vs. FREQUENCY
0
VDD = 3V
= 1.6mW
P
OUT
= 16Ω
R
-20
L
-40
-60
CROSSTALK (dB)
-80
-100
0.01 100
LEFT TO RIGHT
RIGHT TO LEFT
FREQUENCY (Hz)
PSRR (dB)
-60
-80
-100
0.01 0.1 101 100
FREQUENCY (kHz)
OUTPUT POWER vs. SUPPLY VOLTAGE
200
fIN = 1kHz
180
= 16Ω
R
MAX4410 toc37
1010.1
L
THD + N = 1%
160
140
120
100
80
OUTPUT POWER (mW)
60
40
20
0
1.8 3.6
INPUTS 180°
OUT OF PHASE
SUPPLY VOLTAGE (V)
IN PHASE
INPUTS
3.33.02.72.42.1
PSRR (dB)
-60
-80
-100
300
250
MAX4410 toc38
200
150
100
OUTPUT POWER (mW)
50
0.01 0.1 101 100
FREQUENCY (kHz)
OUTPUT POWER vs. SUPPLY VOLTAGE
fIN = 1kHz
= 16Ω
R
L
THD + N = 10%
0
1.8 3.6
INPUTS 180°
OUT OF PHASE
SUPPLY VOLTAGE (V)
INPUTS
IN PHASE
3.33.02.72.42.1
MAX4410 toc39
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
8 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(C1 = C2 = 2.2µF, THD + N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
OUTPUT POWER vs. SUPPLY VOLTAGE
MAX4410 toc40
SUPPLY VOLTAGE (V)
OUTPUT POWER (mW)
3.33.02.72.42.1
20
40
60
80
100
120
140
0
1.8 3.6
fIN = 1kHz
R
L
= 32Ω
THD + N = 1%
INPUTS 180°
OUT OF PHASE
INPUTS
IN PHASE
OUTPUT POWER vs. SUPPLY VOLTAGE
MAX4410 toc41
SUPPLY VOLTAGE (V)
OUTPUT POWER (mW)
3.33.02.72.42.1
40
20
60
80
100
120
140
160
180
0
1.8 3.6
fIN = 1kHz
R
L
= 32Ω
THD + N = 10%
INPUTS
IN PHASE
INPUTS 180°
OUT OF PHASE
OUTPUT POWER vs. LOAD RESISTANCE
MAX4410 toc42
LOAD RESISTANCE (Ω)
OUTPUT POWER (mW)
10k1k100
40
20
60
80
100
120
140
160
0
10 100k
VDD = 3V
f
IN
= 1kHz
THD + N = 1%
INPUTS 180°
OUT OF PHASE
INPUTS
IN PHASE
OUTPUT POWER vs. LOAD RESISTANCE
MAX4410 toc43
LOAD RESISTANCE (Ω)
OUTPUT POWER (mW)
10k1k100
50
100
150
200
250
0
10 100k
INPUTS
IN PHASE
INPUTS 180°
OUT OF PHASE
VDD = 3V
f
IN
= 1kHz
THD + N = 10%
OUTPUT POWER vs. LOAD RESISTANCE
MAX4410 toc44
LOAD RESISTANCE (Ω)
OUTPUT POWER (mW)
10k1k100
5
10
15
20
25
30
35
40
45
0
10 100k
INPUTS 180°
OUT OF PHASE
INPUTS IN
PHASE
VDD = 1.8V
f
IN
= 1kHz
THD + N = 1%
OUTPUT POWER vs. LOAD RESISTANCE
MAX4410 toc45
LOAD RESISTANCE (Ω)
OUTPUT POWER (mW)
10k1k100
10
20
30
40
50
60
70
0
10 100k
INPUTS 180°
OUT OF PHASE
INPUTS IN
PHASE
VDD = 1.8V
f
IN
= 1kHz
THD + N = 10%
POWER DISSIPATION
vs. OUTPUT POWER
MAX4410 toc46
OUTPUT POWER (mW)
POWER DISSIPATION (mW)
16012040 80
50
100
150
200
250
300
350
400
0
0 200
INPUTS 180°
OUT OF PHASE
fIN = 1kHz
R
L
= 16Ω
V
DD
= 3V
P
OUT
= P
OUTL + POUTR
INPUTS
IN PHASE
POWER DISSIPATION
vs. OUTPUT POWER
MAX4410 toc47
OUTPUT POWER (mW)
POWER DISSIPATION (mW)
16012040 80
20
40
60
80
120
100
140
160
180
0
0 200
INPUTS 180°
OUT OF PHASE
fIN = 1kHz
R
L
= 32Ω
V
DD
= 3V
P
OUT
= P
OUTL + POUTR
INPUTS
IN PHASE
POWER DISSIPATION
vs. OUTPUT POWER
MAX4410 toc48
OUTPUT POWER (mW)
POWER DISSIPATION (mW)
50403010 20
20
40
60
80
100
120
140
0
060
INPUTS 180°
OUT OF PHASE
fIN = 1kHz
R
L
= 16Ω
V
DD
= 1.8V
P
OUT
= P
OUTL + POUTR
INPUTS
IN PHASE
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
_______________________________________________________________________________________ 9
Typical Operating Characteristics (continued)
(C1 = C2 = 2.2µF, THD + N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
FREQUENCY (kHz)
101
0.1 100
OUTPUT SPECTRUM vs. FREQUENCY
MAX4410 toc54
OUTPUT SPECTRUM (dB)
-100
-80
-60
-40
-20
0
-120
VIN = 1V
P-P
fIN = 1kHz
R
L
= 32Ω
A
V
= -1V/V
70
60
50
40
30
20
POWER DISSIPATION (mW)
10
0
10
0
-10
-20
GAIN (dB)
-30
-40
-50
90
80
70
60
50
40
30
OUTPUT POWER (mW)
20
10
0
POWER DISSIPATION
vs. OUTPUT POWER
INPUTS
IN PHASE
INPUTS 180°
OUT OF PHASE
fIN = 1kHz
= 32Ω
R
L
= 1.8V
V
DD
= P
P
OUT
OUTL + POUTR
060
OUTPUT POWER (mW)
MAX4410 toc49
50403010 20
GAIN FLATNESS vs. FREQUENCY
MAX4410 toc51
VDD = 3V
= -1V/V
A
V
= 16Ω
R
L
100
10 1k 10k 1M100k 10M
FREQUENCY (Hz)
OUTPUT POWER vs. CHARGE-PUMP
CAPACITANCE AND LOAD RESISTANCE
C1 = C2 = 2.2µF
C1 = C2 = 1µF
C1 = C2 = 0.68µF
C1 = C2 = 0.47µF
10 50
LOAD RESISTANCE (Ω)
fIN = 1kHz
THD + N = 1%
INPUTS IN PHASE
403020
MAX4410 toc53
80
60
40
20
0
-20
-40
-60
-80
-100
GAIN/PHASE (dB/DEGREES)
-120
-140
-160
-180
10
8
6
4
OUTPUT RESISTANCE (Ω)
2
0
GAIN AND PHASE vs. FREQUENCY
GAIN
PHASE
VDD = 3V
= 1000V/V
A
V
= 16Ω
R
L
100 10k 100k 1M 10M
1k
FREQUENCY (Hz)
CHARGE-PUMP OUTPUT RESISTANCE
vs. SUPPLY VOLTAGE
V
= GND
IN_
= 10mA
I
PVSS
NO LOAD
1.8 3.6
SUPPLY VOLTAGE (V)
3.33.02.72.42.1
MAX4410 toc50
MAX4410 toc52
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
10 ______________________________________________________________________________________
Typical Operating Characteristics (continued)
(C1 = C2 = 2.2µF, THD + N measurement bandwidth = 22Hz to 22kHz, T
A
= +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX4410 toc55
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
2.71.80.9
2
4
6
8
10
0
0 3.6
SHUTDOWN SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX4410 toc56
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (µA)
2.71.80.9
2
4
6
8
10
0
0 3.6
SHDNL = SHDNR = GND
EXITING SHUTDOWN
MAX4410 toc57
OUTR
SHDNR
2V/div
500mV/div
200µs/div
fIN = 1kHz
R
L
= 32Ω
SHDNL = GND
POWER-UP/DOWN WAVEFORM
MAX4410 toc58
OUT_
OUT_FFT
V
DD
3V
20dB/div
10mV/div
0V
200ms/div
FFT: 25Hz/div
R
L
= 32Ω
V
IN_
= GND
-100dB
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
______________________________________________________________________________________ 11
Pin Description
PIN BUMP
TSSOP UCSP
1B2SHDNL Active-Low, Left-Channel Shutdown. Connect to VDD for normal operation.
2A3PV
3 A4 C1P Flying Capacitor Positive Terminal
4 B4 PGND Power Ground. Connect to SGND.
5 C4 C1N Flying Capacitor Negative Terminal
6D4PVSSCharge-Pump Output
7D3SVSSAmplifier Negative Power Supply. Connect to PVSS.
8 D2 OUTL Left-Channel Output
9D1SVDDAmplifier Positive Power Supply. Connect to PVDD.
10 C1 INL Left-Channel Audio Input
11 C2 OUTR Right-Channel Output
12 B1 SHDNR Active-Low, Right-Channel Shutdown. Connect to VDD for normal operation.
13 A1 INR Right-Channel Audio Input
14 A2 SGND Signal Ground. Connect to PGND.
NAME FUNCTION
DD
Charge-Pump Power Supply. Powers charge-pump inverter, charge-pump logic, and
oscillator.
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
12 ______________________________________________________________________________________
Detailed Description
The MAX4410 stereo headphone driver features Maxim’s
patented DirectDrive architecture, eliminating the large
output-coupling capacitors required by traditional singlesupply headphone drivers. The device consists of two
80mW Class AB headphone drivers, undervoltage lockout (UVLO)/shutdown control, charge-pump, and comprehensive click-and-pop suppression circuitry (see
Typical Application Circuit). The charge pump inverts the
positive supply (PV
DD
), creating a negative supply
(PVSS). The headphone drivers operate from these bipolar supplies with their outputs biased about GND (Figure
1). The drivers have almost twice the supply range compared to other 3V single-supply drivers, increasing the
available output power. The benefit of this GND bias is
that the driver outputs do not have a DC component typically VDD/2. Thus, the large DC-blocking capacitors are
unnecessary, improving frequency response while conserving board space and system cost.
Each channel has independent left/right, active-low
shutdown controls, making it possible to optimize
power savings in mixed-mode, mono/stereo operation.
The device features an undervoltage lockout that prevents operation from an insufficient power supply and
click-and-pop suppression that eliminates audible transients on startup and shutdown. Additionally, the
MAX4410 features thermal overload and short-circuit
protection and can withstand ±8kV ESD strikes on the
output pins.
DirectDrive
Traditional single-supply headphone drivers have their
outputs biased about a nominal DC voltage (typically
half the supply) for maximum dynamic range. Large
coupling capacitors are needed to block this DC bias
from the headphone. 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 driver.
Maxim’s patented DirectDrive architecture uses a
charge pump to create an internal negative supply voltage. This allows the outputs of the MAX4410 to be
biased about GND, almost doubling dynamic range
while operating from a single supply. With no DC component, there is no need for the large DC-blocking
capacitors. Instead of two large (220µF, typ) tantalum
capacitors, the MAX4410 charge pump requires two
small ceramic capacitors, conserving board space,
reducing cost, and improving the frequency response
of the headphone driver. See the Output Power vs.
Charge-Pump Capacitance and Load Resistance
graph in the Typical Operating Characteristics for
details of the possible capacitor sizes. There is a low
DC voltage on the driver outputs due to amplifier offset.
However, the offset of the MAX4410 is typically 0.5mV,
which, when combined with a 32Ω load, results in less
than 16µA of DC current flow to the headphones.
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 raises some issues:
1) When combining a microphone and headphone on
a single connector, the microphone bias scheme
typically requires a 0V reference.
2) The sleeve is typically grounded to the chassis.
Using this biasing approach, the sleeve must be
isolated from system ground, complicating product
design.
3) During an ESD strike, the driver’s ESD structures
are the only path to system ground. Thus, the driver
must be able to withstand the full ESD strike.
Figure 1. Traditional Driver Output Waveform vs. MAX4410
Output Waveform
V
OUT
CONVENTIONAL DRIVER-BIASING SCHEME
V
OUT
DirectDrive BIASING SCHEME
V
DD
VDD/2
GND
+V
GND
-V
DD
DD
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
______________________________________________________________________________________ 13
4) 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 possible damage to the drivers.
Low-Frequency Response
In addition to the cost and size disadvantages of the DCblocking capacitors required by conventional headphone amplifiers, these capacitors limit the amplifier’s
low-frequency response and can distort the audio signal.
1) The impedance of the headphone load and the DC-
blocking capacitor form a highpass filter with the
-3dB point set by:
where RLis the headphone impedance and C
OUT
is
the DC-blocking capacitor value. The highpass filter
is required by conventional single-ended, single
power-supply headphone drivers to block the midrail
DC bias component of the audio signal from the
headphones. The drawback to the filter is that it can
attenuate low-frequency signals. Larger values of
C
OUT
reduce this effect but result in physically larger, more expensive capacitors. Figure 2 shows the
relationship between the size of C
OUT
and the result-
ing low-frequency attenuation. Note that the -3dB
point for a 16Ω headphone with a 100µF blocking
capacitor is 100Hz, well within the normal audio
band, resulting in low-frequency attenuation of the
reproduced signal.
2) The voltage coefficient of the DC-blocking capacitor
contributes distortion to the reproduced audio signal
as the capacitance value varies as a function of the
voltage change across the capacitor. At low frequencies, the reactance of the capacitor dominates
at frequencies below the -3dB point and the voltage
coefficient appears as frequency-dependent distortion. Figure 3 shows the THD + N introduced by two
different capacitor dielectric types. Note that below
100Hz, THD + N increases rapidly.
The combination of low-frequency attenuation and frequency-dependent distortion compromises audio
reproduction in portable audio equipment that emphasizes low-frequency effects such as multimedia laptops, as well as MP3, CD, and DVD players. By
eliminating the DC-blocking capacitors through
DirectDrive technology, these capacitor-related deficiencies are eliminated.
Charge Pump
The MAX4410 features a low-noise charge pump. The
320kHz switching frequency is well beyond the audio
range, and thus does not interfere with the audio signals. The switch drivers feature a controlled switching
speed that minimizes noise generated by turn-on and
turn-off transients. By limiting the switching speed of the
switches, the di/dt noise caused by the parasitic bond
wire and trace inductance is minimized. Although not
typically required, additional high-frequency noise attenuation can be achieved by increasing the size of C2
(see Typical Application Circuit).
Figure 2. Low-Frequency Attenuation for Common DC-Blocking
Capacitor Values
Figure 3. Distortion Contributed by DC-Blocking Capacitors
f
dB
−=3
2π
1
RC
L OUT
0
-3
-5
-10
-15
-20
ATTENUATION (dB)
-25
-30
-35
10
1
0.1
THD + N (%)
0.01
0.001
0.0001
LF ROLL OFF (16Ω LOAD)
330µF
220µF
100µF
33µF
10 1k
ADDITIONAL THD + N DUE
TO DC-BLOCKING CAPACITORS
ALUM/ELEC
10 100k
FREQUENCY (Hz)
-3dB CORNER FOR
100µF IS 100Hz
100
FREQUENCY (Hz)
TANTALUM
10k1k100
MAX4410 fig02
MAX4410 fig03
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
14 ______________________________________________________________________________________
Shutdown
The MAX4410 features two shutdown controls allowing
either channel to be shut down or muted independently.
SHDNL controls the left channel while SHDNR controls
the right channel. Driving either SHDN_ low disables the
respective channel, sets the driver output impedance to
about 1kΩ, and reduces the supply current to less than
10µA. When both SHDN_ inputs are driven low, the
charge pump is also disabled, further reducing supply
current draw to 6µA. The charge pump is enabled once
either SHDN_ input is driven high.
Click-and-Pop Suppression
In traditional single-supply audio drivers, the outputcoupling capacitor is a major contributor of audible
clicks and pops. Upon startup, the driver charges the
coupling capacitor to its bias voltage, typically half the
supply. Likewise, on shutdown the capacitor is discharged to GND. This results in a DC shift across the
capacitor, which in turn, appears as an audible transient
at the speaker. Since the MAX4410 does not require
output-coupling capacitors, this does not arise.
Additionally, the MAX4410 features extensive click-andpop suppression that eliminates any audible transient
sources internal to the device. The Power-Up/Down
Waveform in the Typical Operating Characteristics
shows that there are minimal spectral components in the
audible range at the output upon startup or shutdown.
In most applications, the output of the preamplifier driving the MAX4410 has a DC bias of typically half the
supply. At startup, the input-coupling capacitor is
charged to the preamplifier’s DC-bias voltage through
the RFof the MAX4410, resulting in a DC shift across
the capacitor and an audible click/pop. Delaying the
rise of the MAX4410’s SHDN_ signals 4 to 5 time constants (200ms to 300ms) based on RINand CINrelative
to the start of the preamplifier eliminates this click/pop
caused by the input filter.
Applications Information
Power Dissipation
Under normal operating conditions, linear power amplifiers 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:
where T
J(MAX)
is +150°C, TAis the ambient tempera-
ture, and θJAis the reciprocal of the derating factor in
°C/W as specified in the Absolute Maximum Ratings
section. For example, θ
JA
of the TSSOP package is
+109.9°C/W.
The MAX4410 has two sources of power dissipation,
the charge pump and the two drivers. 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 traces improve the maximum
power dissipation in the package.
Thermal overload protection limits total power dissipation in the MAX4410. When the junction temperature
exceeds +140°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.
Output Power
The device has been specified for the worst-case scenario— when both inputs are in phase. Under this condition, the drivers simultaneously draw current from the
charge pump, leading to a slight loss in headroom of
VSS. In typical stereo audio applications, the left and
right signals have differences in both magnitude and
phase, subsequently leading to an increase in the maximum attainable output power. Figure 4 shows the two
extreme cases for in and out of phase. In reality, the
available power lies between these extremes.
Figure 4. Output Power vs. Supply Voltage with Inputs In/Out
of Phase
P
DISSPKG MAX
()
TT
=
−
J MAX A
()
θ
JA
TOTAL HARMONIC DISTORTION PLUS
100
10
0.1
THD + N (%)
0.01
0.001
NOISE vs. OUTPUT POWER
VDD = 3V
= -1V/V
A
V
= 16Ω
R
L
= 10kHz
f
IN
1
OUTPUTS IN
PHASE
0 100 15050 200
OUTPUT POWER (mW)
OUTPUTS
180° OUT OF
PHASE
ONE
CHANNEL
MAX4410 fig04
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
______________________________________________________________________________________ 15
Powering Other Circuits from a
Negative Supply
An additional benefit of the MAX4410 is the internally
generated, negative supply voltage (-V
DD
). This voltage
is used by the MAX4410 to provide the ground-referenced output level. It can, however, also be used to
power other devices within a design. Current draw from
this negative supply (PV
SS
) should be limited to 5mA,
exceeding this will affect the operation of the headphone driver. The negative supply voltage appears on
the PVSSpin. A typical application is a negative supply
to adjust the contrast of LCD modules.
When considering the use of PVSSin this manner, note
that the charge-pump voltage at PVSSis roughly proportional to -VDDand is not a regulated voltage. The
charge-pump output impedance plot appears in the
Typical Operating Characteristics.
Component Selection
Gain-Setting Resistors
External feedback components set the gain of the
MAX4410. Resistors RFand RIN(see Typical Application
Circuit) set the gain of each amplifier as follows:
To minimize VOS, set RFequal to 10kΩ. Values other
than 10kΩ increase VOSdue to the input bias current,
which in turn increases the amount of DC current flow
to the speaker.
Compensation Capacitor
The stability of the MAX4410 is affected by the value of
the feedback resistor (RF). The combination of RFand
the input and parasitic trace capacitance introduces an
additional pole. Adding a capacitor in parallel with R
F
compensates for this pole. Under typical conditions
with proper layout, the device is stable without the
additional capacitor.
Input Filtering
The input capacitor (C
IN
), in conjunction with R
IN,
forms a
highpass filter that removes the DC bias from an incoming signal (see Typical Application Circuit). The AC-coupling 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:
Choose RINaccording to the Gain-Setting Resistors sec-
tion. Choose the C
IN
such that f
-3dB
is well below the
lowest frequency of interest. Setting f
-3dB
too high affects
the low-frequency response of the amplifier. Use capacitors whose dielectrics have low-voltage coefficients,
such as tantalum or aluminum electrolytic. Capacitors
with high-voltage coefficients, such as ceramics, may
result in increased distortion at low frequencies.
Other considerations when designing the input filter
include the constraints of the overall system and the
actual frequency band of interest. Although high-fidelity
audio calls for a flat-gain response between 20Hz and
20kHz, portable voice-reproduction devices such as
cellular phones and two-way radios need only concentrate on the frequency range of the spoken human voice
(typically 300Hz to 3.5kHz). In addition, speakers used
in portable devices typically have a poor response
below 150Hz. Taking these two factors into consideration, the input filter may not need to be designed for a
20Hz to 20kHz response, saving both board space and
cost due to the use of smaller capacitors.
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. Table 1
lists suggested manufacturers.
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. Increasing the value of C1 improves
load regulation and reduces the charge-pump output
resistance to an extent. See the Output Power vs.
Charge-Pump Capacitance and Load Resistance
graph in the Typical Operating Characteristics. Above
2.2µF, the on-resistance of the switches and the ESR of
C1 and C2 dominate.
f
RC
dB
IN IN
−=3
1
2π
Table 1. Suggested Capacitor Manufacturers
Note: Please indicate you are using the MAX4410 when contacting these component suppliers.
R
AV=−
F
R
IN
Taiyo Yuden 800-348-2496 847-925-0899 www.t-yuden.com
TDK 847-803-6100 847-390-4405 www.component.tdk.com
SUPPLIER PHONE FAX WEBSITE
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
16 ______________________________________________________________________________________
Output Capacitor (C2)
The output capacitor value and ESR directly affect the
ripple at PVSS. 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. See the Output Power
vs. Charge-Pump Capacitance and Load Resistance
graph in the Typical Operating Characteristics.
Power-Supply Bypass Capacitor
The power-supply bypass capacitor (C3) lowers the output impedance of the power supply, and reduces the
impact of the MAX4410’s charge-pump switching transients. Bypass PVDDwith C3, the same value as C1, and
place it physically close to the PVDDand PGND pins
(refer to the MAX4410 EV kit for a suggested layout).
Adding Volume Control
The addition of a digital potentiometer provides simple
volume control. Figure 5 shows the MAX4410 with the
MAX5408 dual log taper digital potentiometer used as
an input attenuator. Connect the high terminal of the
MAX5408 to the audio input, the low terminal to ground
and the wiper to C
IN
. Setting the wiper to the top position passes the audio signal unattenuated. Setting the
wiper to the lowest position fully attenuates the input.
Layout and Grounding
Proper layout and grounding are essential for optimum
performance. Connect PGND and SGND together at a
single point on the PC board. Connect all components
associated with the charge pump (C2 and C3) to the
PGND plane. Connect PV
DD
and SVDDtogether at the
device. Connect PV
SS
and SVSStogether at the
device. Bypassing of both supplies is accomplished
by charge-pump capacitors C2 and C3 (see Typical
Application Circuit). Place capacitors C2 and C3 as
close to the device as possible. Route PGND and all
traces that carry switching transients away from SGND
and the traces and components in the audio signal
path. Refer to the layout example in the MAX4410 EV
kit datasheet.
When using the MAX4410 in a UCSP package, make
sure the traces to OUTR (bump C2) are wide enough
to handle the maximum expected current flow. Multiple
traces may be necessary.
UCSP Considerations
For general UCSP information and PC layout considerations, refer to the Maxim Application Note: Wafer-
Level Ultra Chip-Scale Package.
OUTL
MAX4410
INL
10
MAX5408
H0
L0
5
6
W0A
7
LEFT AUDIO
INPUT
13
W1A
10
C
IN
R
IN
C
IN
RIGHT AUDIO
INPUT
INR
OUTR
R
F
R
F
11
8
H1
L1
12
11
R
IN
Figure 5. MAX4410 and MAX5408 Volume Control Circuit
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
______________________________________________________________________________________ 17
Typical Application Circuit
2.2µF
C
IN
R
12
(B1)
SHDNR
10kΩ
IN
10
(C1)
INL
SGND
CLICK-AND-POP
SUPPRESSION
SGND
1.8V to 3.6V
CHANNEL
C3
2.2µF
3
(A4)
C1P
C1
5
C1N
(C4)
(A3)
PV
DD
CHARGE
PUMP
2
9
(D1)
SV
DD
SHUTDOWN
CONTROL
AUDIO IN
SHDNL
UVLO/
MAX4410
1µF
LEFT
1
(B2)
R
F
10kΩ
SV
DD
8
(D2)
OUTL
HEADPHONE
JACK
SV
SS
SV
DD
11
(C2)
OUTR
PV
SS
6
(D4)
C2
2.2µF
( ) DENOTE BUMPS FOR UCSP.
SV
7
(D3)
SV
PGND
SS
4
(B4)
SGND
14
(A2)
RIGHT
CHANNEL
AUDIO IN
C
1µF
IN
R
IN
10kΩ
INR
13
(A1)
SS
R
F
10kΩ
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
18 ______________________________________________________________________________________
Pin Configurations
Chip Information
TRANSISTOR COUNT: 4295
PROCESS: BiCMOS
TOP VIEW
(BUMP SIDE
DOWN)
MAX4410
123
4
TOP VIEW
A
B
C
D
INR SGND PV
SHDNR SHDNL
INL OUTR
SV
OUTL SV
DD
UCSP (B16-2)
SHDNL
C1P
DD
PGND
C1N
PV
SS
SS
PV
PV
C1P
C1N
1
2
DD
3
4
MAX4410
5
6
SS
7
SS
14
SGND
13
INR
12
SHDNR
11
OUTRPGND
INL
10
9
SV
DD
OUTLSV
8
TSSOP
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
______________________________________________________________________________________ 19
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
16L,UCSP.EPS
MAX4410
80mW, DirectDrive Stereo Headphone Driver
with Shutdown
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.
20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
TSSOP4.40mm.EPS
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