MAXIM MAX9892ERT+

19-4295; Rev 0; 10/08
Shunt Mode Audio Click-and-Pop Eliminator
The MAX9892 is an audio click-and-pop eliminator for
portable multimedia devices. Operating from a 1.7V to
3.6V supply, the MAX9892 connects to the output of the
existing system amplifier and provides a low-impedance path to ground during startup and shutdown. The
inputs INL and INR accept voltage swings from VDD to
5.5V below VDD. See the Setting the Supply Voltage
section for more information. The power-up and powerdown transients are shunted to ground to prevent clicks
and pops from becoming audible.
The MAX9892 features two low-impedance analog
switches controlled by MUTE that opens and closes the
switches. The switches are open during normal operation and have no impact on the output signal. During
startup and shutdown of the amplifier, the MAX9892
can be activated to short the outputs to ground and
prevent clicks and pops from pulling current through
the headphones.
The MAX9892 is available in 6-bump UCSP (1mm x
1.52mm x 0.6mm) and 6-pin µDFN (2mm x 2mm x
0.75mm) packages. The MAX9892 is specified over the
-40°C to +85°C temperature range.
Applications
Features
♦ Distortion-Free, Click-and-Pop Elimination
♦ Less than 1µA Supply Current
♦ 1.7V to 3.6V Single-Supply Operation
♦ Tiny Packages
6-Bump UCSP (1mm x 1.52mm x 0.6mm)
6-Pin µDFN (2mm x 2mm x 0.75mm)
Ordering Information
TEMP RANGE
PIN-PACKAGE
MAX9892ERT+
PART
-40°C to +85°C
6 UCSP
MAX9892ELT+
-40°C to +85°C
6 µDFN
+Denotes a lead-free/RoHS-compliant package.
Pin Configurations
TOP VIEW
(BUMPS ON BOTTOM)
Mobile Phones
1
2
3
INL
GND
INR
Smart Phones
Mobile Internet Devices
A
Portable Gaming Consoles
Portable Media Players
MAX9892
Notebook Computers
B
VDD
MUTE
SET
Typical Operating Circuit
RSERIES
HEADPHONE
AMPLIFIER
UCSP
TOP VIEW
RSERIES
INL
MUTE
VDD
SET
6
5
4
INR
MAX9892
1.7V TO 3.6V
MAX9892
MUTE
VDD
0.1μF
+
SET
GND
1
INL
C SET
2
3
GND
INR
μDFN
________________________________________________________________ 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
MAX9892
General Description
MAX9892
Shunt Mode Audio Click-and-Pop Eliminator
ABSOLUTE MAXIMUM RATINGS
VDD, MUTE, SET to GND..........................................-0.3V to +6V
INL, INR to GND .................................(VDD - 6V) to (VDD + 0.3V)
Continuous Current In/Out of VDD ......................................30mA
Continuous Current In/Out of MUTE ...................................30mA
Continuous Current In/Out of SET.......................................30mA
Continuous Current In/Out of INL, INR and GND .............390mA
Continuous Power Dissipation (TA = +70°C)
6-Bump UCSP (derate 3.9mW/°C above +70°C) .....308.3mW
6-Pin µDFN (derate 4.5mW/°C above +70°C) ..........357.8mW
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
Bump Temperature (soldering)
Reflow ..........................................................................+235°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
(VDD = 3.0V, VGND = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Supply Voltage Range
VDD
Guaranteed by RON test
1.7
5.5
V
Recommended Supply Voltage
Range
VDD
(Note 2)
1.7
3.6
V
Supply Current
IDD
VDD = 5.5V, TA = +25°C (Note 3)
1
µA
VDD
V
Input Voltage Range
VIN
Guaranteed by input leakage current test
Turn-On Time (Figure 1)
tON
Measured from MUTE = GND and input
voltage settled to 90% of its final value
CSET = 500pF
Turn-Off Time (Figure 1)
tOFF
Turn-On Time Resistor
RSET
Switch On-Resistance
RON
0.6
VDD 5.5V
130
4
10
CSET = 50pF
1
CSET = 50nF
1000
CSET = 500pF
350
VDD = 3.0V
800
IIN
MUTE Leakage Current
IMUTE
MUTE Input-Voltage High
VIH
MUTE Input-Voltage Low
VIL
TA = +25°C
ms
1300
kΩ
2
Ω
1
RSERIES = 30Ω, RLOAD = 16Ω
Input Leakage Current
17
0.3
VDD = 1.7V
VDD = 5.5V
Click-and-Pop Reduction
ns
35
dB
VIN = VDD - 5.5V, VDD = 1.7V
±1
VIN = VDD, VDD = 5.5V
±1
VDD = 5.5V, VMUTE = 0 or 5.5V, TA = +25°C
±1
1.5
µA
µA
V
0.4
V
Note 1: All devices are 100% production tested at TA = +25°C. All temperature limits are guaranteed by design.
Note 2: Operating within the recommended supply voltage range ensures that negative audio signals are not limited by the device.
Supply voltages above the recommended supply voltage range may limit the headphone amplifier’s maximum output voltage.
Note 3: Supply current is measured when switches are off.
2
_______________________________________________________________________________________
Shunt Mode Audio Click-and-Pop Eliminator
CLICK AND POP vs. RSERIES
0.7
0.6
-30
-40
-50
-60
RON (Ω)
800
600
200
0.1
INTO SHUTDOWN
-90
0
0
10
20 30 40 50 60 70 80 90 100
0
5
10 15 20 25 30 35 40 45 50
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
0.6
0.4
4.5
5.5
SWITCH TURN-OFF/ON TIME
-20
0.2
3.5
CLICK AND POP vs. VDD
TESTED WITH THE MAX4338
CLICK AND POP (dBV)
0.8
2.5
VDD (V)
0
MAX9892 toc04
1.0
1.5
CSET (nF)
RSERIES (Ω)
MAX9892 toc06
MAX9892 toc05
0
0.4
0.2
OUT OF SHUTDOWN
-80
0.5
0.3
400
-70
CSET = 500pF
MUTE
2V/div
-40
-60
OUT OF SHUTDOWN
IN_
2V/div
-80
INTO SHUTDOWN
0
-100
2.5
3.5
4.5
5.5
1.5
2.5
VDD (V)
3.5
4.5
5.5
2ms/div
VDD (V)
CROSSTALK vs. FREQUENCY
0
MAX9892 toc07
1.5
-20
CROSSTALK (dB)
IDD (μA)
0.8
MAX9892 toc03
1000
tOFF (ms)
CLICK AND POP (dBV)
-20
1200
MAX9892 toc02
MAX9892 toc01
TESTED WITH THE MAX4338
-10
RON vs. SUPPLY VOLTAGE
tOFF vs. CSET
0
-40
-60
-80
-100
-120
0.01
0.1
1
10
100
FREQUENCY (kHz)
_______________________________________________________________________________________
3
MAX9892
Typical Operating Characteristics
(VDD = 3.0V, VGND = 0, TA = +25°C, unless otherwise noted.)
Shunt Mode Audio Click-and-Pop Eliminator
MAX9892
Pin Description
UCSP
µDFN
BUMP
PIN
A1
1
INL
A2
2
GND
Ground
A3
3
INR
Right-Channel Input. Connect INR in between the output coupling capacitor and the
headphone jack.
B1
6
MUTE
B2
5
VDD
Power Supply
B3
4
SET
Turn-Off Time Set. Connect an external capacitor in between SET and GND to set the switch
open delay; see the Setting the Turn-Off Time section for more information.
NAME
FUNCTION
Left-Channel Input. Connect INL in between the output coupling capacitor and the headphone
jack.
Active-Low Enable
Timing Diagram
MUTE
GND
VDD
IN_
GND
VDD - 5.5V
tOFF
RON
tON
0.5Ω
Figure 1. Turn-On/Off Time
4
_______________________________________________________________________________________
Shunt Mode Audio Click-and-Pop Eliminator
The MAX9892 is the second-generation click-and-pop
eliminator designed to be used with conventional headphone amplifiers. The MAX9892 works by adding a lowimpedance current path from the headphone side of
the DC-blocking capacitor to ground. Drive MUTE low
when turning off the amplifier, and high when enabling
the amplifier. A short turn-on time allows the switches in
the MAX9892 to close before the DC-blocking capacitors have significantly discharged, eliminating clicks
and pops at amplifier turn-off. An adjustable turn-off
time allows the delay to be set to mask all clicks and
pops during amplifier turn-on.
Setting the Turn-Off Time
The MAX9892 features a SET input that allows the turnoff time to be adjusted from 1ms to 1000ms to match
the click-and-pop profile of the amplifier startup. The
value of an external capacitor sets the switch open
delay, as shown in the following equation:
where VAMP is the supply voltage of the amplifier, and
I2 is the current through R2. For a signal of ±2V in reference to GND, the MAX9892 supply can be set from 2V
to 3.5V.
Selecting Series Resistors
A series resistor (RSERIES), as shown in the Typical
Operating Circuit, is necessary to achieve optimal clickand-pop reduction. See the Click and Pop vs. RSERIES
graph in the Typical Operating Characteristics for
details on how much click-and-pop reduction to expect
for a given series resistor.
Layout Considerations
Bypass VDD to GND with a 0.1µF capacitor. The 0.1µF
bypass capacitor should be positioned as close as
possible to VDD. Minimize trace length from GND to
solid system ground plane to ensure optimum performance.
Refer to the MAX9892 Evaluation Kit for a proven PCB
layout.
tON (ms) = 0.02 x CSET (pF)
When the headphone amplifier is enabled, the
MAX9892 automatically waits the set delay time before
opening the analog switches. This allows amplifier turnon click and pop to be eliminated.
A
Applications Information
Setting the Supply Voltage
The MAX9892 operates from 1.7V to 3.6V supply voltage. The inputs, INL and INR, accept voltage swings
from VDD to VDD - 5.5V. The audio signal applied to a
headphone is ground biased, meaning that the signal
swings just as much negative as positive. Since the
MAX9892 input voltage is limited to VDD - 5.5V on the
negative side, the voltage on VDD must be set properly
to pass the audio signal when the switch is open
(Figure 2).
A voltage-divider can be used to scale down an available supply voltage as shown in Figure 3. The voltagedivider allows the creation of a supply voltage for the
MAX9892 that is low enough to allow the negative portion of the audio signal to pass. When using large resistances for the voltage-divider, the supply current
affects what resistors to use. Select R2 between 10kΩ
to 1MΩ for a given supply voltage. Use the following
equation to calculate the R1:
R1 =
VDD
IN_
GND
VDD - 5.5V
B
VDD
IN_
GND
VDD - 5.5V
Figure 2. Proper Supply Selected for a Given Input Signal.
A: Supply Voltage with a Large Signal;
B: Supply Voltage with a Small Signal
(VAMP − VDD )
I2 + IDD
_______________________________________________________________________________________
5
MAX9892
Detailed Description
MAX9892
Shunt Mode Audio Click-and-Pop Eliminator
UCSP Applications Information
For the latest application details on UCSP construction,
dimensions, tape-carrier information, printed circuit
board techniques, bump-pad layout, and recommended reflow temperature profile, as well as the latest information on reliability testing results, refer to Application
Note 1891: Understanding the Basics of the WaferLevel Chip-Scale Package (WL-CSP) at www.maximic.com/ucsp. See Figure 4 for the recommended
MAX9892 PCB footprint.
HEADPHONE
AMP VDD
R1
VDD
MAX9892
R2
0.1μF
GND
45±5μm
Figure 3. Scaling Down the Supply Voltage with a Voltage
Divider
250μm
Figure 4. PCB Footprint Recommendation Diagram
Chip Information
PROCESS: BiCMOS
6
_______________________________________________________________________________________
Shunt Mode Audio Click-and-Pop Eliminator
PACKAGE CODE
DOCUMENT NO.
6 UCSP
R6-1A1+1
21-0228
6 µDFN
L622-1
21-0164
UCSP.EPS
PACKAGE TYPE
_______________________________________________________________________________________
7
MAX9892
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
Package Information (continued)
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
A
D
b
e
6, 8, 10L UDFN.EPS
MAX9892
Shunt Mode Audio Click-and-Pop Eliminator
N
AAA
AAA
SOLDER
MASK
COVERAGE
E
PIN 1
0.10x45∞
L
PIN 1
INDEX AREA
L1
1
SAMPLE
MARKING
A
A
(N/2 -1) x e)
7
C
L
C
L
b
L
A
A2
A1
L
e
e
EVEN TERMINAL
ODD TERMINAL
PACKAGE OUTLINE,
6, 8, 10L uDFN, 2x2x0.80 mm
21-0164
8
_______________________________________________________________________________________
B
1
2
Shunt Mode Audio Click-and-Pop Eliminator
COMMON DIMENSIONS
MAX.
SYMBOL
A
MIN.
NOM.
0.70
0.75
0.80
A1
0.15
0.20
0.25
A2
D
E
0.020
1.95
1.95
0.025
2.00
2.00
0.035
2.05
2.05
L
0.30
0.40
0.10 REF.
0.50
L1
PACKAGE VARIATIONS
PKG. CODE
N
e
b
(N/2 -1) x e
L622-1
6
0.65 BSC
0.30±0.05
1.30 REF.
L822-1
8
0.50 BSC
0.25±0.05
1.50 REF.
L1022-1
10
0.40 BSC
0.20±0.03
1.60 REF.
PACKAGE OUTLINE,
6, 8, 10L uDFN, 2x2x0.80 mm
21-0164
B
2
2
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 9
© 2008 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
MAX9892
Package Information (continued)
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.