Click here for production status of specific part numbers.
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
General Description
The MAX4060/MAX4061/MAX4062 are differential-input
microphone preamplifiers optimized for notebook and
PDA audio systems. These devices feature adjustable
gain with excellent power-supply rejection and commonmode rejection ratios, making them ideal for lownoise
applications in portable audio systems.
The MAX4060/MAX4062 are capable of switching their
output between the differential input and a single-ended
auxiliary microphone amplifier input. In addition, the
MAX4060/MAX4062 have a low-noise microphone bias
generator. The differential gain of the MAX4061/MAX4062
is set with a single resistor. The MAX4060 has a fixed gain
of 10V/V and is PC99/2001 compliant. The MAX4061
includes a complete shutdown mode. In shutdown, the
supply current is reduced to 0.3μA and the current to the
microphone bias is cut off for ultimate power savings.
The MAX4060 operates from a 4.5V to 5.5V single supply and the MAX4061/MAX4062 operate from 2.4V to
5.5V. All devices are specified over the extended operating temperature range, -40°C to +85°C. The MAX4060/
MAX4061 are available in tiny 8-pin TDFN (3mm x 3mm
x 0.8mm) and 8-pin μMAX® packages. The MAX4062 is
available in a 10-pin μMAX package.
Features
●● 2.4V to 5.5V Single-Supply Operation
●● Adjustable Gain or Fixed-Gain Options
●● High PSRR (86dB at 1kHz)
●● High CMRR (70dB at 1kHz)
●● Low Input-Referred Noise
●● Integrated Microphone Bias
●● 750μA Supply Current
●● 0.3μA Shutdown Current
●● ±4kV ESD Protection (AUX_IN)
●● Rail-to-Rail Outputs
●● THD+N: 0.04% at 1kHz
●● Available in Space-Saving Packages
• 8-Pin TDFN (MAX4060/MAX4061)
• 8-Pin μMAX (MAX4060/MAX4061)
• 10-Pin μMAX (MAX4062)
Typical Operating Circuit
2.4V TO 5.5V
BIAS
4
VCC
Applications
●● Notebook Audio
Systems
●● Tablet PCs
●● PDA Audio Systems
Ordering Information
PART
MAX4060ETA+
MAX4060EUA+
MAX4061ETA+
MAX4061EUA+
MAX4062EUB+
TEMP
RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
8 AUX_IN
x10
INT/AUX 1
BIAS
PINPACKAGE
8 TDFN-EP*
8 µMAX
8 TDFN-EP*
8 µMAX
10 µMAX
TOP
MARK
ABY
—
ABZ
—
—
*EP = Exposed pad.
+Denotes a lead(Pb)-free/RoHS-compliant package.
Pin Configurations and Selector Guide appear at end of
data sheet.
μMAX is a registered trademark of Maxim Integrated Products, Inc.
19-2408; Rev 4; 11/18
MAX4060
●● USB Audio Peripherals
●● AES-42-Compliant
Microphones
●● Signal Conditioning
OUT 2
5 IN+
x10
6 IN-
BIAS
BIAS 3
VBIAS
GND
7
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Absolute Maximum Ratings
Supply Voltage (VCC to GND). ................................-0.3V to +6V
Any Other Pin to GND............................... -0.3V to (VCC + 0.3V)
Duration of Short Circuit to GND or VCC...................Continuous
Continuous Input Current (any pin)...................................±10mA
Continuous Power Dissipation (TA = +70°C)
8-Pin TDFN (derate 24.4mW/°C above +70°C)......1951.2mW
8-Bump μMAX (derate 4.8mW/°C above +70°C)......387.8mW
10-Bump μMAX (derate 8.8mW/°C above +70°C)....707.3mW
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
(VCC = 3V for MAX4061/MAX4062, VCC = 5V for MAX4060, VGND = 0V, VSHDN = VCC, VINT/AUX = 0V, RG = 11.11kΩ,
RL = 100kΩ to 1.5V, RBIAS = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
Supply Voltage Range
VCC
Supply Current
ICC
Output Common-Mode Voltage
Slew Rate
Supply Current in Shutdown
Output Short-Circuit Current
VOCM
SR
ISHDN
ISC
CONDITIONS
Inferred from
PSRR test
MIN
VOS
Common-Mode Input Voltage
Range
VCM
Maximum Differential Input Voltage
Small-Signal Bandwidth
Input Resistance
Input Resistance Match
VDIFFMAX
BW-3dB
RIN
RMATCH
Input Noise-Voltage Density
en
RMS Output Noise Voltage
VNRMS
www.maximintegrated.com
MAX
2.4
5.5
MAX4060
4.5
5.5
1.25
AV = 10V/V
0.75
1.2
1.5
1.75
±1
VSHDN = 0V, MAX4061
30
To VCC
30
AV = 1V/V, MAX4061/MAX4062
V
mA
V
1
µA
mA
±0.1
1
UNITS
V/µs
0.001
To GND
DIFFERENTIAL INPUT (VINT/AUX = 0V for MAX4060/MAX4062, default for MAX4061)
Input Offset Voltage
TYP
MAX4061/MAX4062
±5
mV
2
V
1
V
600
kHz
Either differential input
100
kΩ
1
%
AV = 10V/V, f = 1kHz
100
AV = 100V/V, f = 1kHz, MAX4061/MAX4062
only
20
AV = 10V/V, BW = 22Hz to 22kHz
125
nV/√Hz
µVRMS
Maxim Integrated │ 2
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Electrical Characteristics (continued)
(VCC = 3V for MAX4061/MAX4062, VCC = 5V for MAX4060, VGND = 0V, VSHDN = VCC, VINT/AUX = 0V, RG = 11.11kΩ,
RL = 100kΩ to 1.5V, RBIAS = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
Total Harmonic Distortion
Plus Noise
THD+N
Differential Gain
AVDIFF
Common-Mode Rejection Ratio
CMRR
Power-Supply Rejection Ratio
PSRR
CONDITIONS
MIN
AV = 10V/V, f = 1kHz, VOUT = 0.7VRMS,
BW = 22Hz to 22kHz
0.04
1.13
1.3
10
10.4
96
100
104
1V < VCM < 2V, VOUT = 0.7VRMS, MAX4060
9.6
10.0
10.4
TA = +25°C
72
RG = 1.01kΩ
VCM = 500mVP-P, f = 1kHz
TA = TMIN to TMAX
70
Input Noise-Voltage Density
en
dB
dB
86
BW-3dB
RIN
V/V
89
60
AUXILIARY INPUT (MAX4060/MAX4062, INT/AUX = VCC)
Input Resistance
UNITS
%
1
RG = 11.11kΩ
VCC = 5V ±100mV, f = 1kHz
Small-Signal Bandwidth
MAX
9.6
1V < VCM < 2V,
VOUT = 0.7VRMS,
MAX4061/MAX4062
RG = open
TYP
200
kHz
100
kΩ
f = 1kHz
45
nV/√Hz
RMS Output Noise Voltage
VNRMS
BW = 22Hz to 22kHz
385
µVRMS
Total Harmonic Distortion
Plus Noise
THD+N
f = 1kHz, BW = 22Hz to 22kHz
0.05
%
Power-Supply Rejection Ratio
PSRR
Voltage Gain
AVAUX
BIAS OUTPUT (MAX4060/MAX4062)
Output Voltage
Output Resistance
Output Noise Voltage
www.maximintegrated.com
VOUT
ROUT
VNRMS
TA = +25°C
TA = TMIN - TMAX
VOUT = 0.7VRMS
65
90
dB
50
-10.7
-10
IBIAS = 0.8mA to GND, MAX4060
2
2.2
IBIAS = 0.5mA to GND, MAX4062
2
2.2
IBIAS = 0.8mA to GND, MAX4060
(TA = +25°C)
2
2.5
IBIAS = 0.5mA to GND, MAX4062
(TA = +25°C)
22
IBIAS = 0.8mA to GND, BW = 22Hz to
22kHz, MAX4060
50
IBIAS = 0.5mA to GND, BW = 22Hz to
22kHz, MAX4062
20
-9.3
V/V
V
kΩ
40
Ω
µVRMS
Maxim Integrated │ 3
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Electrical Characteristics (continued)
(VCC = 3V for MAX4061/MAX4062, VCC = 5V for MAX4060, VGND = 0V, VSHDN = VCC, VINT/AUX = 0V, RG = 11.11kΩ,
RL = 100kΩ to 1.5V, RBIAS = ∞, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
MAX4060
Power-Supply Rejection Ratio
PSRR
MAX4062
IBIAS = 0.8mA to GND,
VCC = 4.5V to 5.5V
MIN
TYP
50
80
IBIAS = 0.8mA, VCC = 5V
+ 100mVP-P, f = 1kHz
IBIAS = 0.5mA to GND,
VCC = 2.4V to 5.5V
MAX
UNITS
70
dB
50
IBIAS = 0.5mA, VCC = 3V
+ 100mVP-P, f = 1kHz
74
71
DIGITAL INPUTS (SHDN for MAX4061 and INT/AUX for MAX4060/MAX4062)
Input Leakage Current
IIN
Input-Voltage High
VINH
Input-Voltage Low
VINL
Shutdown Enable Time
Shutdown Disable Time
tON
tOFF
VIN = 0V or VCC
±1
0.7 x
VCC
µA
V
0.3 x
VCC
V
MAX4061
10
µs
MAX4061
10
µs
Note 1: All specifications are 100% tested at TA = +25°C. Specification limits over temperature (TA = TMIN to TMAX) are guaranteed
by design, not production tested.
Note 2: MAX4062 requires a 1μF capacitor from BIAS to ground.
www.maximintegrated.com
Maxim Integrated │ 4
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Typical Operating Characteristics
(VCC = 3V (MAX4061/MAX4062), VCC = 5V for MAX4060, AV = 10V/V, RL ≥ 100kΩ to 1.5V, SHDN = VCC (MAX4061 only),
TA = +25°C, unless otherwise noted.)
PSRR (dB)
-6
10
100
1k
10k
100k
AV = 100V/V
10
100
1k
10k
100k
0
1M
-40 -25 -10
5
20
35
50
65
SHUTDOWN SUPPLY CURRENT
vs. TEMPERATURE
OUTPUT-VOLTAGE HIGH
vs. TEMPERATURE
0.5
0.4
0.3
0.2
AV = 10V/V
NO LOAD
2.5
3.0
3.5
4.0
4.5
5.0
5.5
MAX4060 toc05
0.1
10
0.01
ILOAD = 50µA
0.001
-40
-15
10
35
60
1
85
-40
-15
10
35
60
TEMPERATURE (°C)
TEMPERATURE (°C)
OUTPUT-VOLTAGE LOW
vs. TEMPERATURE
OUTPUT-VOLTAGE HIGH
vs. LOAD CURRENT
OUTPUT-VOLTAGE LOW
vs. LOAD CURRENT
VOH = VCC - VOUT
150
VOH (mV)
VOL (mV)
200
100
75
-15
10
35
TEMPERATURE (°C)
www.maximintegrated.com
60
50
25
85
0
VCC = 3V
150
100
50
ILOAD = 50µA
250
VCC = 3V
125
10
300
85
MAX4060 toc09
MAX4060 toc07
175
ILOAD = 2.5mA
-40
ILOAD = 2.5mA
SUPPLY VOLTAGE (V)
1000
100
1
VOL (mV)
2.0
VOH = VCC - VOUT
100
MAX4060 toc08
0.1
10
1000
VOH (mV)
0.6
100
80
MAX4060 toc06
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX4060 toc04
TEMPERATURE (°C)
SHUTDOWN SUPPLY CURRENT (nA)
SUPPLY CURRENT (mA)
0.4
FREQUENCY (Hz)
0.7
1
VCC = 3V
0.6
FREQUENCY (Hz)
0.8
0
-120
1M
VCC = 5V
0.2
-100
-12
0.9
AV = 10V/V
-80
-9
-15
-60
SUPPLY CURRENT vs. TEMPERATURE
0.8
SUPPLY CURRENT (mA)
-20
-40
-3
1.0
MAX4060 toc02
VCC = 5V
0
GAIN (dB)
0
MAX4060 toc01
3
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY (DIFF INPUT)
MAX4060 toc03
GAIN vs. FREQUENCY
(NO LOAD)
0
1
2
3
LOAD CURRENT (mA)
4
5
0
0
1
2
3
4
5
LOAD CURRENT (mA)
Maxim Integrated │ 5
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Typical Operating Characteristics (continued)
(VCC = 3V (MAX4061/MAX4062), VCC = 5V for MAX4060, AV = 10V/V, RL ≥ 100kΩ to 1.5V, SHDN = VCC (MAX4061 only),
TA = +25°C, unless otherwise noted.)
2.200
2.175
VCC = 3V
0.1
THD+N (%)
2.225
VCC = 5V
0.01
VOUT = 2.26VP-P
MAX4060 toc12
VOUT = 2.26VP-P
2.250
1
MAX4060 toc11
1
THD+N (%)
MIC BIAS VOLTAGE (V)
2.275
IBIAS = 800mA
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (AUX INPUT)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY (DIFF INPUT)
MAX4060 toc10
2.300
MAX4060
MIC BIAS VOLTAGE vs. TEMPERATURE
VCC = 3V
0.1
VCC = 5V
0.01
2.150
2.125
2.100
-40
-15
10
35
60
85
0.001
100
1k
10k
100k
0.001
10
100
1k
10k
FREQUENCY (Hz)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT AMPLITUDE
(DIFF INPUT, VCC = 3V)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT AMPLITUDE
(DIFF INPUT, VCC = 5V)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT AMPLITUDE
(AUX INPUT, VCC = 3V)
f = 1kHz
10
BW = 22kHz
1
THD+N (%)
1
THD+N (%)
f = 1kHz
0.1
BW = 22kHz
MAX4060 toc14
10
MAX4060 toc13
BW = 22kHz
MAX4060 toc15
FREQUENCY (Hz)
1
0.1
0.1
f = 1kHz
f = 10kHz
f = 10kHz
0.001
f = 10kHz
0.01
0.01
0
0.5
1.0
1.5
2.0
2.5
3.0
0.001
0
0.5
1.0
1.5
2.0
2.5
3.0
0.01
3.5
0.001
0
0.5
1.0
1.5
2.0
2.5
OUTPUT VOLTAGE (VP-P)
OUTPUT VOLTAGE (VP-P)
OUTPUT VOLTAGE (VP-P)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. OUTPUT AMPLITUDE
(AUX INPUT, VCC = 5V)
INPUT-REFERRED NOISE
vs. FREQUENCY (DIFF INPUT)
MAX4060
MIC BIAS OUTPUT NOISE
BW = 22kHz
700
(nV/√Hz)
0.1
VCC = 5V
BW = 22Hz TO 22kHz
600
1
f = 1kHz
3.0
MAX4060 toc18
MAX4060 toc17
800
MAX4060 toc16
10
THD+N (%)
100k
TEMPERATURE (°C)
10
THD+N (%)
10
500
400
5µV/div
300
f = 10kHz
0.01
200
100
0.001
0
0.5
1.0
1.5
2.0
2.5
OUTPUT VOLTAGE (VP-P)
www.maximintegrated.com
3.0
3.5
0
10
100
1k
10k
100k
100ms/div
FREQUENCY (Hz)
Maxim Integrated │ 6
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Typical Operating Characteristics (continued)
(VCC = 3V (MAX4061/MAX4062), VCC = 5V for MAX4060, AV = 10V/V, RL ≥ 100kΩ to 1.5V, SHDN = VCC (MAX4061 only),
TA = +25°C, unless otherwise noted.)
SMALL-SIGNAL TRANSIENT RESPONSE
FOR DIFF INPUT
MAX4062
MIC BIAS OUTPUT NOISE
MAX4060 toc20
MAX4060 toc19
VCC = 5V
BW = 22Hz TO 22kHz
INPUT
5mV/div
5µV/div
OUTPUT
50mV/div
100ms/div
10µs/div
SMALL-SIGNAL TRANSIENT RESPONSE
FOR AUX INPUT
LARGE-SIGNAL TRANSIENT RESPONSE
FOR DIFF INPUT
MAX4060 toc22
MAX4060 toc21
INPUT
100mV/div
INPUT
5mV/div
OUTPUT
1V/div
OUTPUT
50mV/div
10µs/div
10µs/div
LARGE-SIGNAL TRANSIENT RESPONSE
FOR AUX INPUT
OUTPUT OVERDRIVEN
MAX4060 toc23
INPUT
200mV/div
MAX4060 toc24
DIFFERENTIAL INPUT
INPUT
500mV/div
OUTPUT
1V/div
10µs/div
www.maximintegrated.com
OUTPUT
1V/div
10µs/div
Maxim Integrated │ 7
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Pin Description
PIN
NAME
FUNCTION
2
INT/AUX
Internal (Differential) or Auxiliary (Single-Ended) Input Select. Drive INT/AUX low
to select internal or high to select auxiliary microphone input.
3
3
OUT
Amplifier Output. OUT is high impedance when in shutdown mode.
3
—
—
BIAS
External Electret Microphone Capsule Bias Output. BIAS has a greater than 2kΩ
output impedance.
4
4
5
5
5
6
VCC
Power Supply. Bypass the VCC to GND with a 0.1µF capacitor.
6
6
7
IN-
7
7
8
GND
8
—
9
AUX_IN
—
1
1
G2
—
2
—
SHDN
Shutdown Input. Drive SHDN high for normal operation. Drive SHDN low for
shutdown mode.
—
—
4
BIAS
External Electret Microphone Capsule Bias Output. Bypass BIAS with 1µF
capacitor to ground.
—
8
10
G1
Gain-Selectable Input. Connect an external resistor between G1 and G2 to set
the gain for the differential amplifier.
—
—
—
EP
Exposed Pad (TDFN Only). Internally connected to GND. Connect to a large
ground plane to minimize thermal performance. Not intended as an electrical
connection point.
MAX4060
MAX4061
MAX4062
1
—
2
IN+
Noninverting Differential Amplifier Input. AC-couple the audio signal into IN+.
Inverting Differential Amplifier Input. AC-couple the audio signal into IN-.
Ground
Single-Ended Input for Auxiliary Microphone. AC-couple the audio signal into
AUX_IN.
Gain-Selectable Input. Connect an external resistor between G1 and G2 to set
the gain for the differential amplifier. (See Adjustable Differential-Gain Setting
section.)
Detailed Description
The MAX4060/MAX4061/MAX4062 are differential microphone preamplifiers providing high-quality audio, optimized for use in computer and mobile applications. These
devices feature rail-to-rail outputs, very high power-supply
rejection, and common-mode rejection, making them
ideal for low-noise applications. The MAX4060/MAX4061/
MAX4062 are particularly effective when layout constraints force the microphone amplifier to be physically
remote from the ECM microphone and/or the rest of the
audio circuitry.
The MAX4060/MAX4062 are capable of switching their
output between the differential input and an inverting
single-ended input. INT/AUX selects either the differential input or single-ended auxiliary input. In addition,
the MAX4060 has an internal bias generator to bias the
microphone in either differential or single-ended modes.
The MAX4061 includes a complete 0.3μA shutdown
www.maximintegrated.com
mode for ultimate power savings. The differential gain of
the MAX4061/MAX4062 is set with a single resistor connected between the G1 and G2 pins. The MAX4060 has
a fixed gain of 10V/V.
Differential Input
The main microphone input is a low-noise, differential
input structure. This is an almost essential element when
faced with amplification of low-amplitude analog signals
in digitally intense environments such as notebook PCs
or PDAs. Used correctly, the advantages over a singleended solution are:
●●
Better power-supply noise rejection.
●●
Less degradation from noise in PC board ground
planes.
●●
The microphone and preamplifier can be placed
physically further apart, easing PC board layout
restrictions.
Maxim Integrated │ 8
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Functional Diagram
2.4V TO 5.5V
BIAS
4
VCC
MAX4060
8 AUX_IN
x10
INT/AUX 1
BIAS
OUT 2
5 IN+
x10
6 IN-
BIAS
BIAS 3
VBIAS
GND
7
Fixed Differential Gain (MAX4060)
Input Capacitors
The MAX4060 has an internal fixed gain of 10V/V for its
differential input. This feature simplifies design, reduces
pin count, footprint, and eliminates external gain-setting
resistors.
The two differential microphone inputs and the single-ended auxiliary input of the MAX4060/MAX4061/
MAX4062 have on-chip bias components, allowing the
user to AC-couple any signals onto the input. The input
resistance is 100kΩ (typ), so the capacitor size may be
chosen accordingly to define the LF rolloff desired. This
can be calculated as:
Adjustable Differential-Gain Setting
The MAX4061/MAX4062 allow the user to alter the gain
to optimize the signal-to-noise ratio (SNR) of their system.
The gain is set by a single external resistor (RG) connected between the G1 and G2 pins, where:
RG = 100kΩ / (AV - 1)
where AV is the required voltage gain.
Hence, an 11.11kΩ resistor yields a gain of 10V/V, or
20dB. Leaving the pins unconnected results in a gain of
1V/V. Gain for the MAX4061/MAX4062 is defined as:
AV = VOUT / (VIN+ - VIN-)
The resistor can be either fixed or variable, allowing the
use of a digitally controlled potentiometer to alter the gain
under software control.
www.maximintegrated.com
CIN = 1 / (2πfCUTRIN)
This assumes a low source impedance driving the inputs.
A further consideration for the differential input is the
effect of these series input capacitors on low-frequency,
common-mode rejection. Any mismatch in the values of
these two capacitors degrades the CMRR at frequencies where the impedance of the capacitor is significant
compared to the input resistance of the amplifier—this is
usually most noticeable at low frequencies. One way to
avoid the need for matched or tight tolerance capacitors
is to deliberately oversize the values on the differential
Maxim Integrated │ 9
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
2.4V TO 5.5V
5
100kΩ
RBIAS
VCC
4 BIAS
VBIAS
CBIAS
MAX4062
9 AUX_IN
x10
INT/AUX 2
OUT 3
6 IN+
7 IN-
G1 10
G2 1
GND
8
Figure 1. MAX4062 with Auxiliary Input Configuration
inputs and to set the lower 3dB point (fCUT) of the amplifier by sizing the output capacitor appropriately.
The input impedance matching on the differential input
is typically 1%, allowing input capacitor matching to be
effective at improving low-frequency PSRR.
Common-Mode Rejection Ratio
The common-mode rejection ratio (CMRR) refers to the
amount of rejection that the amplifier is capable of providing to any signal applied equally to the IN+ and INinputs.
In the case of amplifying low-level microphone signals in
noisy digital environments, it is a key figure of merit. In
audio circuits, this is generally measured for VIN as an
AC signal:
CMRR(dB) = ADM / ACM
where ADM is the differential gain, ACM is the commonmode gain.
Auxiliary Input
The auxiliary input is a single-ended input intended to be
used with a jack-socket-type microphone input (Figure 1).
Internal DC-bias components (as on the main inputs) allow
the input signal to be AC-coupled. Mechanically switched
jack sockets can be used in conjunction with the INT/AUX
select pin, allowing the auxiliary microphone input to be
automatically selected when a jack socket is inserted.
Microphone Bias Voltage
MAX4060
The MAX4060 has a microphone bias voltage designed
to comply with the Microsoft/Intel PC99/2001 audio standard. It features source impedance of greater than 2kΩ,
and delivers more than 2V of bias when loaded with a current of 800μA. This limits operation of this part to supplies
between 4.5V to 5.5V (see Figure 2).
Input voltages are sufficiently small such that the output is
not clipped in either differential or common-mode application. The topology used in the MAX4061/MAX4062 means
that the CMRR actually improves at higher differential
gains—another advantage of using differential sensing.
www.maximintegrated.com
Maxim Integrated │ 10
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
4.5V TO 5.5V
4
VCC
MICROPHONE
INPUT
MAX4060
8 AUX_IN
x10
3 BIAS
RBIAS
INT/AUX
1
OUT
2
VBIAS
5 IN+
x10
6 INGND
7
Figure 2. MAX4060 Used for Biasing a Microphone
MAX4061/MAX4062
The MAX4062 has a lower bias voltage and low-impedance outputs (optimum electret bias resistor can then be
set externally). This gives a low-noise, flexible solution
that can run from 2.4V to 5.5V, suitable for handheld
devices such as PDAs that typically have audio power
supplies in the 3V region (see Figure 3).
In applications where the differential microphone is placed
some distance from the MAX4060/MAX4061/MAX4062,
using a remote differential bias scheme as shown in
Figure 4 can provide improved noise rejection.
Output
MAX4060/MAX4061 DC Bias
The output voltage has a DC-bias voltage independent
of the power supplies, resulting in superior PSRR performance. The MAX4061 output is high impedance when the
part is in shutdown mode. AC-coupling the output into the
next audio stage (e.g., CODEC) is recommended.
www.maximintegrated.com
Applications Information
Shutdown Mode
The MAX4061 features a low-power, complete shutdown
mode. When SHDN goes low, the supply current drops
to 0.3μA, the output enters a high-impedance state, and
the bias current to the microphone is switched off. Driving
SHDN high enables the amplifier. SHDN should not be
left unconnected.
Power Supplies and Layout
The MAX4060 operates from a 4.5V to 5.5V single supply and the MAX4061/MAX4062 operate from a 2.4V to
5.5V single supply. Bypass the power supply with a 0.1μF
capacitor to ground. In systems where analog and digital
grounds are available, the MAX4060/MAX4061 should be
connected to the analog ground.
Maxim Integrated │ 11
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
2.4V TO 5.5V
5
VCC
4 BIAS
0.1µF
VBIAS
9 AUX_IN
MAX4062
x10
0.1µF
2.2kΩ
RG
11kΩ
2.2kΩ
INT/AUX 2
10 G1
0.1µF
OUT 3
1 G2
6 IN+
7 IN0.1µF
GND
8
Figure 3. MAX4062 Used to Bias a Microphone Connected to the Auxiliary Input and the Differential Input
www.maximintegrated.com
Maxim Integrated │ 12
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
2.4V TO 5.5V
5
VCC
4 BIAS
VBIAS
MAX4062
0.1µF
9 AUX_IN
2.2kΩ
x10
0.1µF
VDD
INT/AUX 2
10 G1
1kΩ
1kΩ
2.2µF
RG
11kΩ
OUT 3
1 G2
0.1µF
6 IN+
7 IN1kΩ
0.1µF
GND
8
1kΩ
2.2µF
Figure 4. Remote Differential Microphone Bias Network Optimizes Noise Rejection in Long-Run, PC Board Traces
Pin Configurations
TOP VIEW
INT/AUX
1
8
AUX_IN
OUT
2
7
GND
BIAS
3
6
IN-
VCC
MAX4060
EP*
4
µMAX/TDFN
5
IN+
G2
1
SHDN
2
OUT
3
VCC
4
MAX4061
EP*
µMAX/TDFN
*CONNECT EP TO GND (TDFN ONLY).
www.maximintegrated.com
8
G1
7
GND
6
IN-
5
IN+
G2 1
INT/AUX
2
OUT
3
BIAS
VCC
10 G1
9
AUX_IN
8
GND
4
7
IN-
5
6
IN+
MAX4062
µMAX
Maxim Integrated │ 13
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Block Diagrams
4.5V TO 5.5V
2.4V TO 5.5V
4
5
VCC
8
VCC
2.4V TO 5.5V
4
VCC
MAX4060
AUX_IN
x10
INT/AUX
3 BIAS
5 IN+
OUT
5
IN+
6
IN-
INT/AUX 2
4 BIAS
VBIAS
x10
MAX4061
2 SHDN
1
MAX4062
8 AUX_IN
2
VBIAS
OUT
OUT 3
6 IN+
6 INx10
GND
3
G1
G2
8
1
GND
7
7 IN-
7
G1
G2
10
1
GND
8
Selector Guide
AUXILIARY
INPUT
DIFF INPUT
GAIN
SINGLE-ENDED
INPUT
GAIN (dB)
MAX4060
✔
20dB
MAX4061
—
ADJ
MAX4062
✔
ADJ
PRODUCT*
MICROPHONE
BIAS
SHUTDOWN
MODE
SUPPLY
VOLTAGE
(V)
20
✔
—
4.5 to 5.5
—
—
✔
2.4 to 5.5
20
✔
—
2.4 to 5.5
*See Block Diagrams.
Chip Information
PROCESS: BiCMOS
www.maximintegrated.com
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maximintegrated.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.
LAND
PATTERN NO.
8 TDFN
T833+2
21-0137
90-0059
8 μMAX
U8+1
21-0036
90-0092
10 μMAX
U10+2
21-0061
90-0330
Maxim Integrated │ 14
MAX4060/MAX4061/
MAX4062
Differential Microphone Preamplifiers with
Internal Bias and Complete Shutdown
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
CHANGED
DESCRIPTION
3
4/11
Added exposed pad information to Pin Description and Pin Configurations sections
4
11/18
Updated Package Information sections
8, 13
14
For pricing, delivery, and ordering information, please visit Maxim Integrated’s online storefront at https://www.maximintegrated.com/en/storefront/storefront.html.
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
© 2018 Maxim Integrated Products, Inc. │ 15
