LMV1088
www.ti.com
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
LMV1088 Dual Input, Far Field Noise Suppression Microphone Amplifier with Automatic
Calibration Ability
Check for Samples: LMV1088
FEATURES
DESCRIPTION
•
•
•
•
•
The LMV1088 amplifies near-field voice signals within
4cm of the microphones while rejecting far-field
acoustic noise greater than 0.5m from the
microphones. Up to 20dB of far-field rejection is
possible in a properly configured and calibrated
system.
1
2
Low Power Consumption
No Added Processing Delay
Automatic Calibration
Space-Saving 36 Bump DSBGA Package
Up to 20dB SNRI
APPLICATIONS
•
•
•
•
•
Mobile Handsets
Mobile and Handheld Two-Way Radios
Bluetooth and Other Powered Headsets
Hand-Held Voice Microphones
Portable Public Address Systems
KEY SPECIFICATIONS
•
•
•
•
•
•
•
(3.3V Supply, Unless Otherwise Specified)
Supply Voltage 2.7V to 5.5 V
Supply Current 1mA (typ)
Signal to Noise Ratio (A-Weighted) 60 dB (typ)
Total Harmonic Distortion 0.1% (typ)
Noise Cancellation 20 dB (typ)
PSRR 85 dB (typ)
Part of the Powerwise® family of energy efficient
solutions, the LMV1088 consumes 1mA of supply
current while providing superior performance to DSP
solutions consuming over 10 times the power.
A fast calibration during the manufacturing test
process allows the LMV1088 to compensate the
entire microphone system. This calibration includes
mismatch in microphone gain and frequency
response, as well as acoustical path variances. The
LMV1088 stores the calibration coefficients in onboard EEPROM. The calibration is initiated by I2C
command or by pin control.
The dual microphone inputs are differential to provide
excellent noise immunity. The microphones are
biased with an internal low-noise bias supply.
1
2
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2007–2013, Texas Instruments Incorporated
LMV1088
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
www.ti.com
Application of the LMV1088
Far-field noise, > 50 cm
Near-Field Voice
Tra
ffic
N
Up to 4 cm
ois
e
Lo ud
LMV1088
Pzure analog solution
provides superior
performance over DSP
solutions
Music
Analog
Filter
Crowd Noise
Anno
unce
men
hin
c
Ma
Near-Field Voice
ts
eN
o
ise
EEPROM
Low-cost
omnidirectional
microphones
Far field noise reduced
by up to 20 dB in properly
configured and calibrated
system
Typical Application
VDD
C1
10 nF
C2
1 PF
VDD
Mic
Bias
*R*
3
1.1 k:
REF
Bias
**2
R
1.1 k:
C3
470 nF
C4
470 nF
C6
470 nF
LPF
Mic2+
Mic2-
C5
470 nF Mic1+
*R*6
1.1 k:
Auxillary Control
T7
Pre-Amp
Gain
Post Amp
Gain
Analog
Noise Canceling
Processor
6 dB
to
36 dB
0 dB
to
12 dB
*C8
OUT
Optimized
Audio
Ouput
Mic1-
*R*5
1.1 k:
2
I C Interface
EEPROM
Calibration
PE
CAL
C7
GND
ADR SDA SCL
100 nF
2
I CVDD
* The value of the low pass filter capacitor is application dependent, see the application section for additional information.
** The value of the microphone resistors is a standard value often used for electric microphones.
Figure 1. Typical Dual Microphone Far Field noise Cancelling Application
2
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
LMV1088
www.ti.com
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
Connection Diagram
A
B
C
D
E
F
6
Mic
Bias
MIC1+
MIC1-
REF
NC
CAL
5
MIC2+
T1
GND
T2
NC
LPF
4
MIC2-
GND
T3
T4
NC
OUT
3
PE
T5
T6
GND
NC
VDD
2
T7
NC
NC
NC
T8
I C
VDD
1
NC
NC
NC
ADR
SCL
SDA
2
Figure 2. 36 Bump DSBGA package (Top View)
See Package Number YPG0036TTA
Figure 3. DSBGA Package View (Bottom View)
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
3
LMV1088
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
www.ti.com
Pin Descriptions
(1)
(2)
(3)
Bump
Number
Pin Name
Pin Type
A1
NC
No Connect
No Connect
A2
T7
Digital Input
Auxiliary_Control pin
A3
PE
Digital Input
A4
MIC2–
Analog Input
microphone 2 input –
A5
MIC2+
Analog Input
microphone 2 input +
A6
Mic Bias
Analog Output
Bias for Microphones
B1
NC
No Connect
No Connect
(1)
B2
NC
No Connect
No Connect
(1)
B3
T5
B4
GND
B5
T1
Pin Function
(2)
Program Enable EEPROM
Float
Ground
(1)
(3)
Amplifier ground
Float
(3)
B6
MIC1+
Analog Input
C1
NC
No Connect
Microphone 1 input +
No Connect
(1)
C2
NC
No Connect
No Connect
(1)
C3
T6
Float
(3)
C4
T3
Float
(3)
C5
GND
Ground
Amplifier ground
C6
MIC1–
Analog Input
Microphone 1 input –
D1
ADR
Digital Input
I2C Address select
D2
NC
No Connect
D3
GND
Ground
D4
T4
Float
(3)
D5
T2
Float
(3)
D6
REF
Analog Reference
Reference Voltage De-coupling
E1
SCL
Digital Input
I2C Clock
E2
T8
Ground
Connect to GND
E3
NC
No Connect
No Connect
(1)
E4
NC
No Connect
No Connect
(1)
E5
NC
No Connect
No Connect
(1)
E6
NC
No Connect
No Connect
(1)
No Connect
(1)
Amplifier ground
2
F1
SDA
Digital Input/Output
I C Data
F2
I2CVDD
Supply
I2C power supply
F3
VDD
Supply
Power Supply
F4
OUT
Analog Output
Optimized Audio Out
F5
LPF
Analog Input
Lowpasss Filter Capacitor
F6
CAL
Digital Input
Calibration Start
Connect NC pins to GND for optimum noise performance.
Force VDD setup for manual calibrations. Force GND setup for calibration circuitry.
Do not ground pins.
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
4
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
LMV1088
www.ti.com
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
Absolute Maximum Ratings
(1) (2)
Supply Voltage
6.0V
Storage Temperature
-85°C to +150°C
ESD Rating
(3)
ESD Rating
(4)
2000V
200V
(5)
150°C
Mounting Temperature
Infrared or Convection (20 sec.)
235°C
Thermal Resistance θJA (DSBGA)
70°C/W
Junction Temperature (TJMAX)
Soldering Information See AN-1112 (SNVA009) “DSBGA Wafers Level Chip Scale Package.”
(1)
(2)
(3)
(4)
(5)
“Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur, including inoperability and degradation of
device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or
other conditions beyond those indicated in the Recommended Operating Conditions is not implied. The Recommended Operating
Conditions indicate conditions at which the device is functional and the device should not be operated beyond such conditions. All
voltages are measured with respect to the ground pin, unless otherwise specified.
If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.
Human body model, applicable std. JESD22-A114C.
Machine model, applicable std. JESD22-A115-A.
The maximum power dissipation must be de-rated at elevated temperatures and is dictated by TJMAX, θJC, and the ambient temperature
TA. The maximum allowable power dissipation is PDMAX = (TJMAX –TA)/ θJA or the number given in the Absolute Maximum Ratings,
whichever is lower. For the LMV1088, TJMAX = 150°C and the typical θJA for this DSBGA package is 70°C/W and for the LLP package
θJA is 64°C/W Refer to the Thermal Considerations section for more information.
Operating Ratings
(1)
Supply Voltage
2.7V to 5.5V
I2CVDD (2)
1.8V to 5.5V
Temperature Range
−40°C to 85°C
(1)
(2)
The Electrical Characteristics tables list ensured specifications under the listed Recommended Operating Conditions except as
otherwise modified or specified by the Electrical Characteristics Conditions and/or Notes. Typical specifications are estimations only and
are not ensured.
The voltage at I2CVDD must not exceed the voltage on VDD.
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
5
LMV1088
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
www.ti.com
Electrical Characteristics 3.3V and 5.0V (1)
Unless otherwise specified, all limits specified for TJ = 25°C, VDD = 3.3V and 5.0V, VIN = 18mVP-P, pass through mode
preamplifier gain = 20dB, postamplifier gain = -2.5dB, RL = 100kΩ, and CL = 4.7pF.
Symbol
SNR
VIN
VOUT
Parameter
LMV1088
Conditions
Typical
ZIN
ZOUT
Limits
(4)
,
Units
(Limits)
Signal-to-Noise Ratio
f = 1kHz, VIN = 18mVPP, A-Weighted
60
dB
Max Input Signal
f = 1kHz and THD+N < 1%
97
mVP-P
AC Output Voltage
f = 1kHz, preamp gain = 36dB
VIN = 30mVP-P
500
mVRMS
800
mV
DC Output Voltage
THD+N
(3)
(2)
Total Harmonic Distortion + Noise
f = 1kHz, VIN = 18mVP-P
Input Impedance
Output Impedance
0.1
%
100
kΩ
Ω
150
RLOAD
CLOAD
ZLOAD
10
10
kΩ (min)
pF (max)
AM
Microphone Pre Amplifier Gain Range
f = 1kHz
6 – 36
dB
AMR
Microphone Pre Amplifier Gain
Adjustment Resolution
f = 1kHz
2
dB
-2.5 – 9.5
dB
0 – 12
dB
3
dB
AP
f = 1kHz Pass Through Mode and
Summing Mode
Post Amplifier Gain Range
f = 1kHz Noise Canceling Mode
(5)
APR
Post Amplifier Gain Adjustment
Resolution
f = 1kHz
ACR
Gain Compensation Range
f = 300Hz – f = 3400Hz
±3
dB (max)
AMD
Gain Matching Difference After
Calibration
f = 300Hz
f = 1kHz
f = 3kHz
0.5
0.5
0.5
dB (max)
dB (max)
dB (max)
TCAL
Calibration Duration
770
ms (max)
Input Referred, Input AC grounded
PSRR
(2)
(3)
(4)
(5)
6
f = 217Hz (100mVP-P)
85
dB
f = 1kHz (100mVP-P)
80
dB
dB
CMRR
Common Mode Rejection Ratio
f = 1kHz,
60
VBM
Microphone Bias Supply Voltage
IBIAS = 1mA
2.0
V
εVBM
Microphone Bias Supply Noise
A-Weighted
10
μVRMS
IBM
Total available Microphone Bias Current
1.2
mA (min)
IDDQ
Supply Quiescent Current
VIN = 0V
1
1.5
mA (max)
IDDCP
Supply Current during Calibration and
Programming
Calibrating or Programming EEPROM
28
50
mA (max)
Supply Current
VIN = 25mVP-P both inputs, Noise
canceling mode
1
1.5
mA (max)
IDD
(1)
Power Supply Rejection Ratio
“Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur, including inoperability and degradation of
device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or
other conditions beyond those indicated in the Recommended Operating Conditions is not implied. The Recommended Operating
Conditions indicate conditions at which the device is functional and the device should not be operated beyond such conditions. All
voltages are measured with respect to the ground pin, unless otherwise specified.
In Pass Through mode, only one microphone input is active. See also I2C Compatible Interface for more information how to configure
the LMV1088.
Typical values represent most likely parametric norms at TA = +25°C, and at the Recommended Operation Conditions at the time of
product characterization and are not specified.
Datasheet min/max specification limits are specified by test, or statistical analysis.
In Noise Canceling Mode there is 2.5dB additional gain before calibration when compared to the other operating modes to compensate
for the gain reduction that is caused by the noise canceling effect.
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
LMV1088
www.ti.com
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
Digital Interface Characteristics
(1) (2)
Unless otherwise specified, all limits specified for TJ = 25°C, I2CVDD within the Operating Rating
Symbol
(1)
(2)
(3)
(4)
Parameter
Conditions
(2)
LMV1088
Typical
(3)
Limits
(4)
Units
(Limits)
VIH
Logic High Input Level
SCL, SDA, ADR, CAL, PE pins
0.6xI2CVDD
V (min)
VIL
Logic Low Input Level
SCL, SDA, ADR, CAL, PE pins
0.4xI2CVDD
V (max)
tsCAL
CAL Setup Time
thCAL
CAL Hold time until calibration is
finished
tsPEC
PE Setup Time
thPEC
PE Hold until calibration is finished
2
ms
770
2
ms (min)
ms
770
ms (min)
“Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur, including inoperability and degradation of
device reliability and/or performance. Functional operation of the device and/or non-degradation at the Absolute Maximum Ratings or
other conditions beyond those indicated in the Recommended Operating Conditions is not implied. The Recommended Operating
Conditions indicate conditions at which the device is functional and the device should not be operated beyond such conditions. All
voltages are measured with respect to the ground pin, unless otherwise specified.
The voltage at I2CVDD must not exceed the voltage on VDD.
Typical values represent most likely parametric norms at TA = +25°C, and at the Recommended Operation Conditions at the time of
product characterization and are not specified.
Datasheet min/max specification limits are specified by test, or statistical analysis.
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
7
LMV1088
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
www.ti.com
Typical Performance Characteristics
Unless otherwise specified, TJ = 25°C, VDD = 3.3V, VIN = 18mVP-P, pass through mode (1), preamplifier gain = 20dB,
postamplifier gain = –2.5dB, RL = 100kΩ, and CL = 4.7pF.
Supply Current
vs.
Supply Voltage
THD+N
vs
Frequency, pass through mode Mic1, VIN = 36mVP-P
2.5
1
THD+N (%)
IDD (mA)
2.0
IMICBIAS = 1 mA
1.5
IMICBIAS = 0 mA
0.1
1.0
0.5
2.7
3.4
4.0
4.7
0.01
10
5.3
100
1k
10k
100k
FREQUENCY (Hz)
VDD (V)
Figure 4.
Figure 5.
THD+N
vs
Frequency, pass through mode Mic2, VIN = 36mVP-P
THD+N
vs
Frequency, Noise canceling mode signal at Mic1, Mic2 AC
shorted, VIN = 36mVP-P
1
THD+N (%)
THD+N (%)
1
0.1
0.01
10
100
1k
10k
0.1
0.01
10
100k
FREQUENCY (Hz)
100
1k
10k
100k
FREQUENCY (Hz)
Figure 6.
Figure 7.
THD+N
vs
Frequency, Noise canceling mode Mic1 AC shorted, signal
at Mic2, VIN = 36mVP-P
THD+N
vs
VIN, pass through mode Mic1
1
10
THD+N (%)
THD+N (%)
1
0.1
0.1
0.01
10
100
1k
10k
0.01
1
100k
FREQUENCY (Hz)
8
100
1000
Vin (mVpp)
Figure 8.
(1)
10
Figure 9.
In Pass Through mode, only one microphone input is active. See also I2C Compatible Interface for more information how to configure
the LMV1088.
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
LMV1088
www.ti.com
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
Typical Performance Characteristics (continued)
Unless otherwise specified, TJ = 25°C, VDD = 3.3V, VIN = 18mVP-P, pass through mode (1), preamplifier gain = 20dB,
postamplifier gain = –2.5dB, RL = 100kΩ, and CL = 4.7pF.
THD+N
vs
VIN, pass through mode Mic2
THD+N
vs
VIN, Noise canceling mode, signal at Mic1, Mic2 AC shorted
1
1
THD+N (%)
10
THD+N (%)
10
0.1
0.01
1
0.1
10
100
0.01
1
1000
10
100
1000
Vin (mVpp)
Vin (mVpp)
Figure 10.
Figure 11.
THD+N
vs
VIN, Noise canceling mode, Mic1 AC shorted, signal at Mic2
PSRR
vs
Frequency, pass through mode Mic1, Mic1+ Mic2 AC
shorted
10
110.0
100.0
90.0
PSRR (dB)
THD+N (%)
1
80.0
0.1
70.0
60.0
0.01
1
10
100
50.0
100
1000
Vin (mVpp)
1k
10k
100k
FREQUENCY (Hz)
Figure 13.
PSRR
vs
Frequency, pass through mode Mic2, Mic1+ Mic2 AC
shorted
PSRR
vs
Frequency, Noise canceling mode, Mic1+ Mic2 AC shorted
110.0
110.0
100.0
100.0
90.0
90.0
PSRR (dB)
PSRR (dB)
Figure 12.
80.0
80.0
70.0
70.0
60.0
60.0
50.0
100
1k
10k
50.0
100
100k
FREQUENCY (Hz)
1k
10k
100k
FREQUENCY (Hz)
Figure 14.
Figure 15.
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
9
LMV1088
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
www.ti.com
Typical Performance Characteristics (continued)
Unless otherwise specified, TJ = 25°C, VDD = 3.3V, VIN = 18mVP-P, pass through mode (1), preamplifier gain = 20dB,
postamplifier gain = –2.5dB, RL = 100kΩ, and CL = 4.7pF.
PSRR
vs
Frequency, Microphone Bias, Mic1+ Mic2 AC shorted
110.0
100.0
PSRR (dB)
90.0
80.0
IMIC = 0 mA
70.0
IMIC = 1 mA
60.0
50.0
40.0
100
1k
10k
100k
FREQUENCY (Hz)
Figure 16.
10
Submit Documentation Feedback
Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LMV1088
LMV1088
www.ti.com
SNAS385J – SEPTEMBER 2007 – REVISED APRIL 2013
APPLICATION DATA
Gain Balance and Gain Budget
In systems where input signals have a high dynamic range, critical noise levels and where the dynamic range of
the output voltage is also limited, careful gain balancing can be essential for the best performance. Having not
enough gain in the Pre Amplifier can result in higher noise levels while to much gain in the Pre Amplifier will
result in clipping and saturation in the noise cancelling processor and output stages.
The gain ranges and maximum signal levels for the different functional blocks is shown in Figure 17. Two
examples are given as a guideline how to select proper gain settings.
Pre Amp
Gain
(6-36 dB)
Post Amp
Gain
(6-18 dB)
Gain
(Max. 9 dB)
OUT+
Analog
Noise
Cancelling
Processor
Mic1
or
Mic2
Maximum
AC Input
Voltage
工商网监
湘ICP备2023018690号
