LX1720.pdf

NOT RECOMMENDED FOR NEW DESIGN
AudioMAX
TM
LX1720
SWITCHING CLASS-D, STEREO POWER AMPLIFIER CONTROLLER IC
T
H E
I
N F I N I T E
P
O W E R
O F
I
P
N N O VA T I O N
R O D U C T I O N
DESCRIPTION
Its high efficiency (>92%) eliminates the
need for heat sinks — even while delivering more than 10WRMS across 8 ohms
per channel (20WRMS stereo) with 0.1 ohm
SO-8 power FETs.
The LX1720's output power is limited
only by external FETs and available supply voltage.
While offering breakthrough performance capabilities for notebooks, the
LX1720 is equally attractive for multimedia systems or to drive full-size home
theatre speakers.
PRODUCT HIGHLIGHT
E F F I C I E N C Y C O M PA R I S O N
100
H E E T
■ Integrated Switching (Class-D) Stereo
Power Amplifier Controller IC
■ Delivers >10WRMS Across 8Ω /Channel
(20WRMS stereo)
■ Output Power Limited Only By External
FETs And Available Supply Voltage
■ Will Drive A Wide Range Of Speakers
■ High Efficiency (>92%)
■ Due To High Efficiency, Power FETs Do Not
Require Heatsinking
■ Audio Bandwidth Of 20Hz to 20kHz
■ Wide Input Voltage Range Of 7V-15V
■ Low Output Signal Distortion <1%
■ High Operating Frequency (350kHz) Helps
To Reduce Output Filter Size
■ Compact Design Minimizes EMI / RFI
OF THE
APPLICATIONS / BENEFITS
CLASS-D AMPLFIER
Notebook Computers:
■ Replaces existing internal low power linear
amplifier with a high efficiency Class-D
amplifier
■ Enables the use of virtually any external
speaker without amplification
■ Precious battery life is extended
■ Fully protected power topology can
withstand shorts or external speaker
failures without damage, overheating or
posing fire hazard
- Average Power Out for 20sec. approx. 512mW
- Across 8.6 Ohm Load
Linfinity's LX1720
Class-D Amplifier
80
Efficiency (%)
S
K E Y F E AT U R E S
IMPORTANT: For the most current data, consult LinFinity's web site: http://www.linfinity.com.
Desktop Computers:
60
40
■ Output power capability of up to 20WRMS
per channel in an area less than 3"x3",
without using expensive heatsinks
■ Greatly reduced power supply
requirements when compared to a linear
solution of same power capabilities
■ Any speakers can be used including
conventional home stereo speakers
■ Very light weight circuitry will not add to
the overall weight of the system
■ Multimedia amplifier can be directly
incorporated on the motherboard using
surface mount components
Highly Integrated
Linear Amplifier
O
20
0
A T A
bs
ol
et
e
The LX1720 is a highly-integrated,
Switching Class-D Stereo Power Amplifier Controller IC with power and
size features that make it ideal for multimedia computer applications, as well as
other applications where high fidelity
sound is required.
With input voltage ranging from 7V15V, the LX1720 is designed to operate
over the full 20Hz to 20kHz audio range.
Signal distortion measurements using
industry standard 1kHz signal yields THD
+ noise levels < 1% (10 watts output).
D
0
5
Audio sample from "Hold On Tight"
by Electric Light Orchestra
10
15
20
APPLICATION NOTE AN-11
Seconds
available on our web site
or call 1-800-LMI-7011
PA C K A G E O R D E R I N F O
TJ (°C)
Maximum
VDD
0 to 70
15V
SSOP
DB Plastic
44-pin
LX1720-01CDB
Note: Available in Tape & Reel.
Append the letter "T" to part number. (i.e. LX1720-01CDBT)
Copyright © 1999
Rev. 1.0 9/99
LINFINITY MICROELECTRONICS INC.
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570
1
PRODUCT DATABOOK 1996/1997
AudioMAX
LX1720
SWITCHING CLASS-D, STEREO POWER AMPLIFIER CONTROLLER IC
P
R O D U C T I O N
A B S O L U T E M A X I M U M R AT I N G S
D
A T A
S
H E E T
PA C K A G E P I N O U T S
(Note 1)
RISLISIS+
RPWM
CPWM
CN
N.C.
CT
RT
RBIAS
GND
AGND
INPUT (R)
INPUT (L)
SLEEP
EAIN (R)
N.C.
EAOUT (R)
FAOUT (R)
EAOUT (L)
EAIN (L)
FAOUT (L)
1
44
2
43
3
42
4
41
5
40
6
39
7
38
8
37
9
36
10
35
11
34
12
33
13
32
14
31
15
30
16
29
17
28
18
27
19
26
20
25
21
24
22
23
bs
ol
et
e
Supply Voltage (PVDD, VDD) ...................................................................... -0.3V to 18V
RPWM .................................................................................................... -0.3V to VCN+0.3V
INPUT (R), INPUT (L) .......................................................................... -0.3V to VCN+0.3V
FBK+(R), FBK-(R), FBK+(L), FBK-(L), SLEEP .............................................. -0.3V to VDD
MUTE (R), MUTE (L) .................................................................................... -0.3V to 6.0V
EAOUT (R), EAOUT (L) ....................................................................... -0.3V to VCN+0.3V
CPWM, CT ............................................................................................. -0.3V to VCN+0.3V
IS+, LIS-, RIS+ ................................................................................................ VDD-2 to VDD
Operating Junction Temperature
Plastic (DB Package) ............................................................................................ 125ºC
Storage Temperature Range ...................................................................... -65°C to 150°C
Lead Temperature (Soldering, 10 seconds) ............................................................ 300°C
Note 1. Exceeding these ratings could cause damage to the device. All voltages are with
respect to Ground. Currents are positive into, negative out of the specified terminal.
T H E R M A L D ATA
DB PACKAGE:
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
65°C/W
FBK- (R)
FBK+ (R)
N.C.
VDD
CP
PVDD
PGND
P- (R)
N- (R)
N+ (R)
P+ (R)
P- (L)
N- (L)
N+ (L)
P+ (L)
PGND
PVDD
FBK- (L)
FBK+ (L)
GND
MUTE (L)
MUTE (R)
DB PACKAGE
(Top View)
Junction Temperature Calculation: TJ = TA + (PD x θJA).
The θJA numbers are guidelines for the thermal performance of the device/pc-board
system. All of the above assume no ambient airflow.
FUNCTIONAL PIN DESCRIPTION
Pin Name
RISLISIS+
Description
Pin Name
Description
Right Channel Current Sense Input
FAOUT (R)
Output of Right Feedback Amp
Left Channel Current Sense Input
EAOUT (L)
Left Channel Error Amplifier Output
Positive Current Sense Input
RPWM
PWM Resistor Connection
CPWM
PWM Capacitor Connection
CN
CT
Oscillator Timing Capacitor Connection
Oscillator Timing Resistor
O
RT
Supply Decoupling for NFET Drivers
RBIAS
Bias Setting Resistor for Error Amps
GND
Ground (2-pins)
EAIN (L)
FAOUT (L)
FBK+(R), FBK-(R)
CP
Supply Decoupling for PFET Drivers
VDD
Analog Supply Voltage
PGND
P+(R), N+(R),
P-(R), N-(R)
INPUT (R)
Right Channel Input
P+(L), N+(L),
INPUT (L)
Left Channel Input
EAIN (R)
Right Channel Feedback Inputs
Output Driver Supply Voltage (2-pins)
Audio Input Ground
EAOUT (R)
Output of Left Feedback Amp
PVDD
AGND
SLEEP
Inverting Input of Left Channel Error Amp
IC Power Ground for the Output Drivers (2-pins)
Right Channel Gate Drive Outputs
Left Channel Gate Drive Outputs
P-(L), N-(L)
FBK+(L), FBK-(L)
Sleep Input
Inverting Input of Right Channel Error Amp
MUTE (R),
Right Channel Error Amplifier Output
MUTE (L)
Left Channel Feedback Inputs
Mute Inputs
NOT RECOMMENDED FOR NEW DESIGN
2
Copyright © 1999
Rev. 1.0 9/99
TM
PRODUCT DATABOOK 1996/1997
AudioMAX
TM
LX1720
SWITCHING CLASS-D, STEREO POWER AMPLIFIER CONTROLLER IC
P
R O D U C T I O N
D
A T A
S
H E E T
ELECTRICAL CHARACTERISTICS
(Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C ≤ TA ≤ 70°C.
Test conditions: RT = 30k, CT = 100pF, VDD = PVDD = 15V.)
Parameter
Symbol
Test Conditions
Min.
LX1720
Typ.
Max.
Units
Oscillator Section
280
330
2.5
200
1
1
2
380
bs
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et
e
Oscillator Frequency
Oscillator Peak Voltage
Oscillator Valley Voltage
Oscillator Max. Frequency
Voltage Stability
Temperature Stability
2
kHz
V
mV
MHz
%
%
Error Amplifiers
Input Offset Voltage
DC Open Loop Gain
Unity Gain Bandwidth
High Output Voltage
Low Output Voltage
Input Common Mode Range
Input Bias Current
5
60
7
IOUT = -100µA
IOUT = +100µA
4
50
5
1
1
mV
dB
MHz
V
mV
V
µA
Input Amplifiers
Stage Gain
Input Impedance
Set by Internal Resistors
3.465
3.5
42
3.535
V/V
kΩ
Feedback Amplifiers
High Output Voltage
Low Output Voltage
Common Mode Rejection
Input Common Mode Range
Input Impedance
Stage Gain
LX1720-01
IOUT = -250µA
IOUT = +250µA
4
50
70
0
Set by Internal Resistors
89
VDD
388
91
93
V
mV
dB
V
kΩ
mV/V
Current Limit Comparators
Voltage Sense Threshold
Comparator Response Time
200
220
500
240
mV
nsec
PWM Comparators
CPWM Delay To Output
250
nsec
RPWM = 75k
75
20
µA
Ω
ISINK = 3mA
ISINK = 75mA
ISOURCE = 3mA
ISOURCE = 75mA, CN = 5.2V (applied externally)
30
1
30
1
100
1.5
100
1.5
mV
V
mV
V
ISINK = 3mA
ISINK = 75mA
ISOURCE = 3mA
ISOURCE = 75mA, CP = 5.2V (applied externally)
30
1
30
1
100
1.5
100
1.5
mV
V
mV
V
PWM Current Generator
O
CPWM Charge Current
Impedance of Internal Discharge FET
Output Drivers For The N-Channel MOSFETs
Ext. NFET Drivers, Low Level Voltage
VOL
Ext. NFET Drivers, High Level Voltage
VOH
Output Drivers For The P-Channel MOSFETs
Ext. PFET Drivers, Low Level Voltage
VOL
Ext. PFET Drivers, High Level Voltage
VOH
NOT RECOMMENDED FOR NEW DESIGN
Copyright © 1999
Rev. 1.0 9/99
3
PRODUCT DATABOOK 1996/1997
AudioMAX
LX1720
SWITCHING CLASS-D, STEREO POWER AMPLIFIER CONTROLLER IC
P
R O D U C T I O N
D
A T A
S
H E E T
ELECTRICAL CHARACTERISTICS
Parameter
Symbol
(Continued)
Test Conditions
Min.
LX1720
Typ.
Max.
Units
Undervoltage Lockout Section
6.3
Start Threshold Voltage
UV Lockout Hysteresis
UVLO Delay To Output Enable
6.5
500
976
6.7
V
mV
clkcyc
Supply Current
1.2
20
5
976
1.45
1.6
µA
mA
clkcyc
V
1.6
1.7
1.8
V
SLEEP Input = 0V, TA = 25°C
SLEEP Input = 2V, VIN = 15V, No MOSFETs Connected
7
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et
e
Sleep Current
Operating Current
Sleep To Output Enable
Sleep Threshold
Mute Section
O
Mute Threshold
NOT RECOMMENDED FOR NEW DESIGN
4
Copyright © 1999
Rev. 1.0 9/99
TM
PRODUCT DATABOOK 1996/1997
AudioMAX
TM
LX1720
SWITCHING CLASS-D, STEREO POWER AMPLIFIER CONTROLLER IC
P
R O D U C T I O N
D
A T A
S
H E E T
BLOCK DIAGRAM
R T
O S C
C T
P G N D
C L K
P V D D
S L E E P
V
R B IA S
V D D
R E G
U V L O
V R E F
B IA S
P - (R )
bs
ol
et
e
C N
E A O U T (R )
E A IN (R )
S
F B K + (R )
Q
E rro r A m p
Q
R
F B K - (R )
O U T
D R IV
A N
P R O T E
C IR C U
IN P U T (R )
M U T E (R )
N - (R )
P + (R )
C L K
F e e d b a c k
A m p
F A O U T (R )
C P
In p u t A m p
P U
E R
D
C T
IT
T
N + (R )
S
IO N
R Y
P - (L )
V D D
V D D
N - (L )
C L K
R P W M
C P W M
S
E A O U T (L )
R
Q
E A IN (L )
E rro r A m p
F B K + (L )
Q
P + (L )
N + (L )
C L K
O
F B K - (L )
M U T E (L )
L IS -
IN P U T (L )
R IS -
IS +
F A O U T (L )
F e e d b a c k
A m p
In p u t A m p
FIGURE 1 — LX1720 Block Diagram
NOT RECOMMENDED FOR NEW DESIGN
Copyright © 1999
Rev. 1.0 9/99
5
PRODUCT DATABOOK 1996/1997
AudioMAX
LX1720
SWITCHING CLASS-D, STEREO POWER AMPLIFIER CONTROLLER IC
P
R O D U C T I O N
D
A T A
S
H E E T
T Y P I C A L A P P L I C AT I O N
V
IN
= 7 V T O
1 5 V
R
6
R
C
1 9
C
1 8
C
C
1 7
5
1 6
IS +
P V D D
L IS -
R IS Q
1
P - (R )
L
L
1
2
P
R
Q
3
Q
4
P + (R )
IN P U T (L )
N + (R )
S L E E P
S L E E P
R M U T E
R M U T E
L M U T E
L M U T E
C
C
R
7
2 1
R
C
C
(R )
Q
6
N - (L )
L
R
1 0
F A O U T (L )
F B K + (R )
F B K + (R )
F B K - (L )
F B K - (L )
F B K + (L )
F B K + (L )
C P W M
F B K - (R )
7
N + (L )
Q
8
4
C
6
C
8
3
L
5
C
3
6
5
F B K -(L )
1 1
L 7
R
C
4
F B K + (L )
L 8
C
7
1 2
A G N D
For detailed application
information please refer to
APPLICATION NOTE AN-11
N
T
C
C
C
P W M
O
F B K - (R )
Q
P + (L )
E A IN (L )
C
4
1 0
C
E A O U T (L )
C
F B K + (R )
2 2
9
L
3
2
F A O U T (R )
R
2 3
R
E A IN
R
5
E A O U T (R )
8
L
Q
P - (L )
2
9
C
2 0
C
1
F B K -(R )
P G N D
L E F T IN
IN P U T (R )
G N D
2 5
T
C
1
C
L X 1 7 2 0
C
R
R T
R
C N
2 4
2
R P W M
C T
C
R IG H T IN
Q
N - (R )
C P
P W M
L E F T
C
R IG H T
bs
ol
et
e
V D D
available on our web site
or call 1-800-LMI-7011
FIGURE 2 — Typical Class-D Stereo Switching Amplifier Circuit Application
NOT RECOMMENDED FOR NEW DESIGN
PRODUCTION DATA - Information contained in this document is proprietary to LinFinity, and is current as of publication date. This document
may not be modified in any way without the express written consent of LinFinity. Product processing does not necessarily include testing of
all parameters. Linfinity reserves the right to change the configuration and performance of the product and to discontinue product at any time.
6
Copyright © 1999
Rev. 1.0 9/99
TM