ETC LX1792CLM

3/11/2002
LX1792
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
INTEGRATED PRODUCTS
P RELIMINARY S PECIFICATION
KEY FEATURES
Low Operating Current: 120µA
Typical
Low Operating Voltage: 0.9V
minimum
Gain set by external resistors
3 Output Switch Resistance
Settings: 48, 24 & 16 Ω
5uVrms input referred noise.
APPLICATIONS
Hearing Aid applications
High impedance speaker
/Transducer applications
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
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DESCRIPTION
The LX1790 consists of a preamplifier
The MSC-LX1792 offers a patent
pending, low voltage, low power, and followed by a fixed gain class D amplifier.
high efficiency amplifier for driving a
The input resistor and feedback
high impedance speaker such as a hearing
resistor is external in the LX1792 making
aid receiver.
it possible to set the gain arbitrarily, up to
The core of the amplifier is built upon approximately 40dB. The feedback
Microsemi’s patented LX1790 class D resistor can also be potentiometer to
facilitate volume control.
amplifier.
PRODUCT HIGHLIGHT
CLOCK
DIN
PRE AMP
Σ
CMP
HBRIDGE
SPEAKER
TJ (°°C)
10 to 55
Copyright  2001
Rev. 0.3,2002-03-11
LM
Plastic MLPM
8-Pin
LX1792CLM
LX1792
PACKAGE ORDER INFO
Plastic Dip
N 14-Pin
LX1792CN
Bare Die
LX1792 bare die
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 1
3/11/2002
LX1792
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
INTEGRATED PRODUCTS
P RELIMINARY S PECIFICATION
PACKAGE PIN OUT
Input Logic Supply Voltage (VDD).......................................-0.3V to +3.0V
Operating Temperature Range ................................................10°C to 55°C
Note:
Exceeding these ratings could cause damage to the device. All voltages are
with respect to Ground. Currents are positive into, negative out of
specified terminal.
VSS
1
8
VDD
OUTN
2
7
OUTP
IMPSEL
3
6
PREOUT
4
5
IN
LM PACKAGE
(Top View)
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ABSOLUTE MAXIMUM RATINGS
FUNCTIONAL PIN DESCRIPTION
PIN NAME
PIN NO
14 PIN DIP
(EVALUATION
SAMPLES)
8
DESCRIPTION
PIN NO
MLPM
PIN
VDD
13
8
Supply Voltage
VSS
2
1
Ground
IN
8
5
Analog Audio Input
OUTP
14
7
Positive Output Voltage
OUTN
1
2
Negative Output Voltage
PREOUT
9
6
Pre amplifier output
IMPSEL
6
3
Output Resistance Select. See Settings table below for selections.
SETTINGS
PIN
IMPSEL=VSS
IMPSEL=VDD
IMPSEL=Floating
IMPSEL
16Ω
24Ω
48Ω
PACKAGE DATA
Copyright  2001
Rev. 0.3,2002-03-11
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 2
P
3/11/2002
LX1792
INTEGRATED PRODUCTS
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
P RELIMINARY S PECIFICATION
Parameter
Symbol
Test Conditions
Min
LX1792
Typ
Max
Units
OPERATING CONDITIONS
Supply Voltage
VDD
Ground
VSS
0.9
1.5
0
V
V
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, the following specifications apply over the operating ambient temperature TA=25°C except where otherwise
noted. Test conditions: VDD=1.3V, VSS=0V, Circuit connected as application schematic on page 5, No load
Parameter
Symbol
Switch Output Resistance @ Low
Drive
Switch Output Resistance @ Med
Drive
Switch Output Resistance @ High
Drive
Test Conditions
Min
LX1792
Typ
ROUT-L
48
ROUT-M
24
ROUT-HI
16
Quiescent Current @ Low Drive
IDDQL
110
Quiescent Current @ Med Drive
IDDQM
120
Quiescent Current @ High Drive
IDDQH
130
3dB Bandwidth – min Frequency
FMIN
3dB Bandwidth – max Frequency
FMAX
40
R1=50k, R2=1000k
Max
Units
Ω
19
µA
100
Hz
50
KHz
FCLK
200
KHz
A1
R1=50k, R2=1000k
32
dB
Power Supply Rejection Ratio
PSRR
Input Reference
R1=50k, R2=1000k
45
dB
Total Harmonic Distortion
THD1
R1=50k, R2=1000k, Vin=5mVrms
0.3
%
Input Referred Noise
VN-20
R1=50k, R2=1000k, 100Hz-10kHz, No weighting
5
µV
Output Switching Frequency
Gain1
FCLK
Output clock frequency
Max absolute DC Offset OutN-OutP
VOFF-NP
No input signal
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RECOMMENDED OPERATING CONDITIONS
140
200
300
KHz
0
0.5
5
mV
ELECTRICALS
Copyright  2001
Rev. 0.3,2002-03-11
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 3
3/11/2002
LX1792
INTEGRATED PRODUCTS
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
P RELIMINARY S PECIFICATION
CHARTS
W W W. Microsemi .COM
CHARTS
Copyright  2001
Rev. 0.3,2002-03-11
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 4
3/11/2002
LX1792
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
INTEGRATED PRODUCTS
P RELIMINARY S PECIFICATION
W W W. Microsemi .COM
LX1790 H-bridge on impedance
30
Ron [Ohm]
25
20
15
10
5
0
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
Supply voltage
Figure 2 – H-Bridge Impedance vs. Supply Voltage (Lowest Impedance Setting)
CHARTS
Copyright  2001
Rev. 0.3,2002-03-11
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 5
3/11/2002
LX1792
INTEGRATED PRODUCTS
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
P RELIMINARY S PECIFICATION
W W W. Microsemi .COM
APPLICATION SCHEMATIC
Transducer/Speaker
C2
Battery
0.9-1.5 V
IMPsel
NC
Volume cntrl
potentiometer
OUTP
PREOUT
R2
CIN
OUTN
VDD
MSC-LX1792
VSS
R1
IN
Microphone
SUGGESTED EXTERNAL APPLICATION COMPONENTS
COMPONENT
SUGGESTED VALUE
CIN
100nF
C2
R2
RX/CX
Copyright  2001
Rev. 0.3,2002-03-11
Input AC coupling capacitor, must be present
For best performance this should be as close as possible to the supply pins
> 25k Ohm
APPLICATION
R1
Description
Input resistor > 25k Ohms
Preamplifier feedback resistor
If the audio source (for example a microphone) has a low power supply rejection an
additional filter for the supply to this have to be added.
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 6
3/11/2002
LX1792
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
INTEGRATED PRODUCTS
P RELIMINARY S PECIFICATION
LM
8-Pin Plastic MLP-Micro Exposed Pad
Dim
A
K
J
E
B
H
I
G
C
N
F
A
B
C
D
E
F
G
H
I
J
K
MILLIMETERS
MIN
MAX
2.90
3.10
2.90
3.10
0.65
0.75
0.15
0.25
1.841 BSC
0.27
0.43
0.65 BSC
1.22 BSC
0
0.10
0.21
0.37
0
0.10
INCHES
MIN
MAX
0.114 0.122
0.114 0.122
0.025 0.029
0.005 0.009
0.075 BSC
0.010 0.016
0.025 BSC
0.048 BSC
0
0.003
0.008 0.014
0
0.003
Internally Connected
together, but
isolated from all
other terminals
D
14-Pin Plastic Dip
A
Dim
B
1
L
J
K
G
D
SEATING PLANE
M
A
B
C
D
F
G
H
J
K
L
M
MILLIMETERS
MIN
MAX
18.54
20.57
6.09
6.60
5.08
0.38
0.51
0.76
1.52
2.54 BSC
1.27
2.28
0.20
0.38
3.18
7.62 BSC
15°
INCHES
MIN
MAX
0.730
0.810
0.240
0.260
0.200
0.015
0.020
0.030
0.060
0.100 BSC
0.050
0.090
0.008
0.015
0.125
0.300 BSC
15°
MECHANICAL
C
F
H
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MECHANICAL – 8 PIN MLPQ PACKAGE OUTLINE
Note:
1. Dimensions do not include mold flash or protrusions;
these shall not exceed 0.155mm(.006”) on any side.
Lead dimension shall not include solder coverage.
Copyright  2001
Rev. 0.3,2002-03-11
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 7
3/11/2002
LX1792
INTEGRATED PRODUCTS
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
P RELIMINARY S PECIFICATION
MECHANICALS
7-PIN BARE DIE
X
Y
MILLIMETERS
MIN
MAX
1.15
1.78
INCHES
MIN
MAX
0.045
0.070
Note:
1. Dimensions do not include mold flash or
protrusions;
these
shall
not
exceed
0.155mm(.006”) on any side. Lead dimension
shall not include solder coverage.
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Dim
MECHANICAL
Copyright  2001
Rev. 0.3,2002-03-11
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 8
3/11/2002
LX1792
INTEGRATED PRODUCTS
Low Voltage, Low Power, AudioMite™
Class-D Audio Amplifier
P RELIMINARY S PECIFICATION
NOTES
W W W. Microsemi .COM
NOTES
Copyright  2001
Rev. 0.3,2002-03-11
Microsemi
INTEGRATED PRODUCTS
5973 Avenida Encinas, Suite 101, Carlsbad 92008, Fax (760) 431-0541
Page 9