MPS MP7740DN

MP7740
15W Class D Mono
Single Ended Audio Amplifer
The Future of Analog IC Technology
DESCRIPTION
FEATURES
The MP7740 is a mono 15W Class D Audio
Amplifier. It is one of MPS’ products of fully
integrated audio amplifiers which dramatically
reduces solution size by integrating the
following:
250mΩ power MOSFETs
Startup / Shutdown pop elimination
Short circuit protection circuits
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The MP7740 utilizes a single ended output
structure capable of delivering 15W into 4Ω
speakers. MPS Class D Audio Amplifiers exhibit
the high fidelity of a Class A/B amplifier at high
efficiencies. The circuit is based on the MPS’
proprietary variable frequency topology that
delivers excellent linearity, fast response time
and operates on a single power supply.
15W Output at VDD = 24V into a 4Ω load
THD+N = 0.05% at 1W, 8Ω
90% Efficiency at 15W & VDD=24V
Low Noise (103µV Typical)
Switching Frequency Up to 1MHz
9.5V to 36V Operation from a Single Supply
Integrated Startup and Shutdown Pop
Elimination Circuit
Thermal and Short Circuit Protection
Integrated Power FETs
Pin Compatible with MP7720
Available in Tiny 8-Pin SOIC Package
APPLICATIONS
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Portable Docking Stations
Surround Sound DVD Systems
Televisions
Flat Panel Monitors
Multimedia Computers
Home Stereo Systems
“MPS” and “The Future of Analog IC Technology” are Registered Trademarks of
Monolithic Power Systems, Inc.
AAM (Analog Adaptive Modulation) is a Trademark of Monolithic Power
Systems, Inc.
TYPICAL APPLICATION
THD+N vs. POUT
VDD=24V,Freq=1kHz,A-wtd
VDD
4
1
2
3
AUDIO
INPUT
VDD
EN
PGND
PIN
MP7740
NIN
BS
AGND
SW
6
20
10
5
8
5
THD+N (%)
OFF ON
7
+
2
1
0.5
0.2
0.1
0.05
0.02
0.01
60m
200m
1
5
20
POUT(W)
MP7740 Rev. 0.9
9/22/2009
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1
MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
ORDERING INFORMATION
Part Number*
Package
Top Marking
Temperature
MP7740DN
SOIC8E
MP7740DN
–40°C to +85°C
*For Tape & Reel, add suffix –Z (eg. MP7740DN–Z); For RoHS compliant packaging, add suffix –LF (eg.
MP7740DN–LF–Z)
PACKAGE REFERENCE
TOP VIEW
PIN
1
8
PGND
NIN
2
7
SW
AGND
3
6
VDD
EN
4
5
BS
EXPOSED PAD
ON BACKSIDE
ABSOLUTE MAXIMUM RATINGS (1)
Thermal Resistance
Supply Voltage VDD ...................................... 40V
BS Voltage .................. VSW – 0.3V to VSW + 6.5V
Enable Voltage VEN ........................–0.3V to +6V
VSW ................... –1V (-5V for <10ns) to VDD + 1V
VPIN, VNIN ................................... –1V to VDD + 1V
AGND to PGND ..........................–0.3V to +0.3V
Continuous Power Dissipation (TA = +25°C)
SOIC8E .................................. 50 ....... 8.........°C
(2)
………………………………………………...2.5W
Junction Temperature ............................... 150°C
Lead Temperature ....................................260°C
Storage Temperature.............. –65°C to +150°C
Recommended Operating Conditions
(3)
(4)
θJA
θJC
Notes:
1) Exceeding these ratings may damage the device.
2) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ (MAX), the junction-toambient thermal resistance θJA, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by PD (MAX) = (TJ
(MAX)-TA)/ θJA. Exceeding the maximum allowable power
dissipation will cause excessive die temperature, and the
regulator will go into thermal shutdown. Internal thermal
shutdown circuitry protects the device from permanent
damage.
3) The device is not guaranteed to function outside of its
operating conditions.
4) Measured on JESD51-7, 4-layer PCB.
Supply Voltage VDD ..........................9.5V to 36V
Operating Temperature TA ........ –40°C to +85°C
MP7740 Rev. 0.9
9/22/2009
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MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
ELECTRICAL CHARACTERISTICS (5, 6)
VDD = 24V, VEN = 5V, TA = +25°C, unless otherwise noted.
Parameters
Symbol Condition
Supply Current
Standby Current
Quiescent Current
Output Drivers
SW On Resistance
Short Circuit Current
Inputs
PIN, NIN Input Common Mode
Voltage Range
PIN, NIN Input Current
EN Enable Threshold Voltage
EN Enable Input Current
Thermal Shutdown
Thermal Shutdown Trip Point
Min
Typ
Max
Units
VEN = 0V
SW=0V
20
1.5
50
3.0
µA
mA
Sourcing and Sinking
Sourcing and Sinking
0.25
4.5
0
VPIN = VNIN = 12V
VEN Rising
VEN Falling
VEN = 5V
0.8
TJ Rising
Thermal Shutdown Hysteresis
VDD
2
1
1.8
1.2
1
Ω
A
VDD – 1.5
V
5
2.5
µA
V
V
µA
150
°C
30
°C
Notes:
5) The device is not guaranteed to function outside its operating rating.
6) Electrical Characteristics are for the IC only with no external components except bypass capacitors.
OPERATING SPECIFICATIONS (7)
Circuit of Figure 1, VDD = 24V, VEN = 5V, TA = +25°C, unless otherwise noted.
Parameters
Standby Current
Quiescent Current
Symbol Condition
VEN = 0V
Min
f = 1KHz, THD+N = 10%, 4Ω
Load
f = 1KHz, THD+N = 10%, 8Ω
Load
POUT = 1W, f = 1kHz, 4Ω Load
POUT = 1W, f = 1kHz, 8Ω Load
f = 1KHz, POUT = 15W, 4Ω Load
f = 1KHz, POUT = 8W, 8Ω Load
Power Output
THD+ Noise
Efficiency
Maximum Power Bandwidth
Dynamic Range
Noise Floor
Power Supply Rejection
A-Weighted
VCC=24V,
Gain=8.25V/V,
VRIPPLE=200mVPP
CR=100µF
Typ
130
13
Max
Units
µA
mA
15
W
8
W
0.05
0.018
90
90
20
97
103
%
%
%
%
kHz
dB
µV
f = 1kHz
-60
dB
f = 100Hz
-60
dB
Notes:
7) Operating Specifications are for the IC in Typical Application circuit (Figure 1).
MP7740 Rev. 0.9
9/22/2009
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MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
PIN FUNCTIONS
Pin #
Name
1
PIN
2
NIN
3
4
AGND
EN
5
BS
6
VDD
7
SW
8
Description
Amplifier Positive Input. PIN is the positive side of the differential input to the amplifier. Use a
resistive voltage divider to set the voltage at PIN to VDD/2. See Figure 1.
Amplifier Negative Input. NIN is the negative side of the differential input to the amplifier. Drive
the input signal and close the feedback loop at NIN. See Figure 1.
Analog Ground. Connect AGND to PGND at a single point.
Enable Input. Drive EN high to turn on the amplifier, low to turn it off.
High-Side MOSFET Bootstrap Input. A capacitor from BS to SW supplies the gate drive
current to the internal high-side MOSFET.
Power Supply Input. VDD is the drain of the high-side MOSFET switch, and supplies the
power to the output stage and the MP7740 internal control circuitry. In addition to the main
bulk capacitor, bypass VDD to PGND with a 1µF X7R capacitor placed close to pins 6 and 8.
Switched Power Output. SW is the output of the MP7740. Connect the LC filter between SW
and the output coupling capacitor. See Figure 1.
Power Ground. Connect PGND to AGND at a single point.
PGND
Exposed
Connect exposed pad to GND plane for proper thermal performance.
Pad
MP7740 Rev. 0.9
9/22/2009
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MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
TYPICAL PERFORMANCE CURVES
20
10
5
20
10
5
2
1
0.5
2
1
0.5
2
1
0.5
0.2
0.1
0.05
0.02
0.01
60m
Freq=1kHz
Freq=10kHz
Freq=100Hz
200m
1
5
20
0.2
0.1
0.05
Freq=1kHz
0.02
0.01
60m
Freq=100Hz
200m
20
0.2
0.1
0.05
2k
10k
+4
+2
+2
+0
-2
-4
-6
-6
-8
-10
1k
10k
40k
-20
-20
-30
-40
-50
-60
AMPLITUDE (dBV)
-10
AMPLITUDE (dBV)
0
-40
-60
-80
FREQUENCY (Hz)
MP7740 Rev. 0.9
9/22/2009
10k
10k
40k
-40
-60
-80
-120
-120
2k
1k
-100
-100
-70
500
100
FREQUENCY (Hz)
0
100
20
FREQUENCY (Hz)
-20
10k
-4
-10
100
2k
-2
-8
20
500
0
+0
-80
20
100
FREQUENCY (Hz)
+4
FREQUENCY (Hz)
AMPLITUDE (dB)
5
AMPLITUDE (dB)
AMPLITUDE (dBr)
THD+N (%)
2
1
0.5
500
1
0.02
0.01
20
POUT(W)
20
10
5
100
0.2
0.1
0.05
Freq=10kHz
POUT(W)
0.02
0.01
20
THD+N (%)
20
10
5
THD+N (%)
THD+N (%)
Circuit of Figure 1, VDD=24V, VEN=5V, AV=8.25V/V, TA = +25°C, unless otherwise noted.
2
4
6
8 10 12 14 16 18 20
2
4
FREQUENCY (KHz)
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8 10 12 14 16 18 20
FREQUENCY (KHz)
5
MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
TYPICAL PERFORMANCE CURVES (continued)
0
0
-20
-20
-20
-40
-60
Right to Left
-80
Left to Right
-100
-40
Right to Left
-60
-80
Left to Right
-100
20 50 100
500 1k 2k
20 50 100
5k 10k 20k
-40
-60
-80
-100
-120
-120
-120
AMPLITUDE (dBV)
0
AMPLITUDE (dB)
AMPLITUDE (dB)
Circuit of Figure 1, VDD=24V, VEN=5V, TA = +25°C, unless otherwise noted.
500 1k 2k
60 100 200 500 1k 2k
5k 10k 20k
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (Hz)
-20
30
-40
25
-60
-80
20
15
60 100 200 500 1k 2k
5k 10k 20k 30k
FREQUENCY (Hz)
0
80
70
60
50
40
30
20
5
-120
VDD=24V,Input Signal Freq=1kHz
100
90
10
-100
Efficiency vs. POUT
EFFICIENCY (%)
35
POUT (W)
AMPLITUDE (dBV)
POUT vs. V DD
Input Signal Freq=1kHz
0
5k 10k 20k
10
0
5
10 15 20 25 30 35 40
0
0
2
VDD (V)
4
6
8 10 12 14 16 18
POUT (W)
Thermal Rise vs. Output Power
VDD=24V
150
130
110
90
70
50
30
10
0
5
10
15
OUTPUT POWER (W)
MP7740 Rev. 0.9
9/22/2009
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6
MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
OPERATION
The MP7740 is a single-ended Class D audio
amplifier. It uses the Monolithic Power Systems
patented Analog Adaptive ModulationTM to
convert the audio input signal into pulses.
These pulses drive an internal high-current
output stage and, when filtered through an
external inductor-capacitor filter, reproduce the
input signal across the load. Because of the
switching Class D output stage, power
dissipation in the amplifier is drastically reduced
when compared to Class A, B or A/B amplifiers
while maintaining high fidelity and low
distortion.
The amplifier uses differential input to the
modulator. PIN is the positive input and NIN is
the negative input. The common mode voltage
of the input is set to half the DC power supply
input voltage (VDD/2) through the resistive
voltage divider. The input capacitor CIN couple
the AC signal at the input.
The amplifier voltage gain is set by the
combination of the input resister RIN and the
feedback resistor RFB and is calculated by the
equation:
AV =
−R FB
R IN
The output driver stage uses two 250mΩ
N-Channel MOSFETs to deliver the pulses to
the LC output filter which in turn drives the load.
To fully enhance the high-side MOSFET, the
gate is driven to a voltage higher than the
source by the bootstrap capacitor between SW
and BS. While the output is driven low, the
bootstrap capacitor is charged from VDD through
an internal circuit on the MP7740. The gate of
the high-side MOSFET is driven high from the
voltage at BS, forcing the MOSFET gate to a
voltage higher than VDD and allowing the
MOSFET to fully turn on, reducing power loss in
the amplifier.
MP7740 Rev. 0.9
9/22/2009
Pop Elimination
The capacitor COUT blocks the DC signal and
pass only AC signals to the load. To insure that
the amplifier passes low frequency signals, the
time constant of COUT*RLOAD needs to be long.
However, when EN is asserted, the capacitor
charges over a long period and in a normal
amplifier can result in a turn on and/or turn off
“pop.” The MP7740 includes integrated circuitry
that eliminates the turn on and turn off pop
associated with the charging of the AC coupling
capacitor.
Short Circuit/Overload Protection
The MP7740 has internal overload and short
circuit protection. The currents in both the highside and low-side MOSFETs are measured and
if the current exceeds the 4.5A short circuit
current limit, both MOSFETs are turned off. The
MP7740 then restarts with the same power up
sequence that is used for normal starting to
prevent a pop from occurring after a short
circuit condition is removed.
A schottky diode (for example, B340LA
manufactured by Diodes Inc) is required for
short-circuit protection, with the cathode
connected to SW and the anode connected to
PGND. Please place the diode as close to the
MP7740 as possible.
If short-circuit protection is not needed, the
Schottky diode can be omitted.
Mute/Enable Function
The MP7740 EN input is an active high enable
control. To enable the MP7740, drive EN with a
2.5V or greater voltage. To disable the
amplifier, drive it below 1V. While the MP7740
is disabled, the VDD operating current is less
than 5µA and the output driver MOSFETs are
turned off.
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MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
APPLICATION INFORMATION
COMPONENT SELECTION
The MP7740 uses a minimum number of external
components to complete a stereo Class D audio
amplifier. The circuit of Figure 1 should be
suitable for most applications, and use the
following sections to determine how to customize
the amplifier for a particular application.
Setting the Voltage Gain
The maximum output voltage swing is limited by
the power supply. To achieve the maximum
power out of the MP7740 amplifier, set the gain
such that the maximum input signal results in the
maximum output voltage swing.
The maximum output voltage swing is ±VDD/2.
For a given input signal voltage, where VIN (pk) is
the peak input voltage, the maximum voltage
gain is:
A V (MAX) =
VDD
2 × VIN (pk )
This voltage gain setting results in the peak
output voltage approaching it’s maximum for the
maximum input signal. In some cases the
amplifier is allowed to overdrive slightly, allowing
the THD to increase at high power levels, and so
a higher gain than AV (max) is required.
Setting the Switching Frequency
The idle switching frequency (the switching
frequency when no audio input is present) is a
function of several variables: the supply voltage
VDD, the timing capacitor CINT and the feedback
resistor RFB. Lower switching frequencies result
in more inductor ripple, causing more quiescent
output voltage ripple and increasing the output
noise
and
distortion.
Higher
switching
frequencies result in more power loss. The
optimum quiescent switching frequency is
approximately 600KHz to 700KHz. Refer to the
Operating Specifications for recommended
values.
MP7740 Rev. 0.9
9/22/2009
Table 1—Switching Frequency vs. VDD, Timing
Capacitor and Feedback Resistor (see Figure 1)
Gain
(V/V)
Gain
(dB)
RFB
(kΩ)
RIN
(kΩ)
CINT
FSW
VDD
(V)
3.9
11.8
39
10
6.8nF
660KHz
12
8.2
18.3
82
10
3.3nF
660KHz
12
8.3
18.4
39
4.7
6.8nF
660KHz
12
12.0
21.6
120
10
2.2nF
610KHz
12
17.4
24.8
82
4.7
3.3nF
660KHz
12
25.5
28.1
120
4.7
2.2nF
610KHz
12
5.6
15.0
56
10
8.2nF
670KHz
24
8.2
18.3
82
10
5.6nF
720KHz
24
11.9
21.5
56
4.7
8.2nF
670KHz
24
12.0
21.6
120
10
4.7nF
620KHz
24
17.4
24.8
82
4.7
5.6nF
720KHz
24
25.5
28.1
120
4.7
4.7nF
620KHz
24
33.0
30.4
330
10
1.8nF
700KHz
24
Choosing the LC Filter
The Inductor-Capacitor (LC) filter converts the
pulse train at SW to the output voltage that drives
the speaker.
The characteristic frequency of the LC filter
needs to be high enough to allow high frequency
audio to the output, yet needs to be low enough
to filter out high frequency products of the pulses
from SW. The characteristic frequency of the LC
filter is:
f0 =
1
2π LC
The voltage ripple at the output is approximated
by the equation:
⎛ f
VRIPPLE ≅ VDD × ⎜⎜ 0
⎝ f SW
⎞
⎟
⎟
⎠
The quality factor (Q) of the LC filter is important.
If this is too low, output noise will increase, if this is
too high, then peaking may occur at high signal
frequencies reducing the passband flatness. The
circuit Q is set by the load resistance (speaker
resistance, typically 4Ω or 8Ω). The Q is
calculated as:
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MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
Q = ω0 ×
L
RLOAD
= 2π × f0 ×
L
RLOAD
ω0 is the characteristic frequency in radians per
second and f0 is in Hz. Use an LC filter with Q
between 0.7 and 1.
The actual output ripple and noise is greatly
affected by the type of inductor and capacitor used
in the LC filter. Use a film capacitor and an
inductor with sufficient power handling capability
to supply the output current to the load. The
inductor
should
exhibit
soft
saturation
characteristics. If the inductor exhibits hard
saturation, it should operate well below the
saturation current. Gapped ferrite, MPP,
Powdered Iron, or similar type toroidal cores are
recommended. If open or shielded bobbin ferrite
cores are used for multi-channel designs, make
sure that the start windings of each inductor line
up (all starts going toward SW pin, or all starts
going toward the output) to prevent crosstalk or
other channel-to-channel interference.
Output Coupling Capacitor
The output AC coupling capacitor COUT serves to
block DC voltages and thus passes only the
amplified AC signal from the LC filter to the load.
The combination of the coupling capacitor, COUT
and the load resistance results in a first-order
high-pass filter. The value of COUT should be
selected such that the required minimum
frequency is still allowed to pass. The output
corner frequency (-3dB point), fOUT, can be
calculated as:
fOUT =
1
2 × π × R LOAD × C OUT
Set the output corner frequency (fOUT) at or below
the minimum required frequency.
The output coupling capacitor carries the full load
current, so a capacitor should be chosen such
that its ripple current rating is greater than the
maximum load current. Low ESR aluminum
electrolytic capacitors are recommended.
Input Coupling Capacitor
The input coupling capacitor CIN is used to pass
only the AC signal at the input. In a typical
system application, the source input signal is
typically centered around the circuit ground, while
the MP7740 input is at half the power supply
voltage (VDD/2). The input coupling capacitor
MP7740 Rev. 0.9
9/22/2009
transmits the AC signal from the source to the
MP7740 while blocking the DC voltage. Choose
an input coupling capacitor such that the corner
frequency (fIN) is less than the passband
frequency. The corner frequency is calculated as:
fIN =
1
2 × π × RIN × CIN
Power Source
For maximum output power, the amplifier circuit
requires a regulated external power source to
supply the power to the amplifier. The higher the
power supply voltage, the more power can be
delivered to a given load resistance, however if
the power source voltage exceeds the maximum
voltage of 36V, the MP7740 may sustain
damage. The power supply rejection of the
MP7740 is excellent (typically -60dB), however
noise at the power supply can get to the output,
so care must be taken to minimize power supply
noise within the pass-band frequencies. Bypass
the power supply with a large capacitor (typically
aluminum electrolytic) along with a smaller 1µF
ceramic capacitor at the MP7740 VDD supply
pins.
PCB Layout
The circuit layout is critical for optimum
performance and low output distortion and noise.
It is highly recommended to duplicate EVB layout
for optimum performance. If change is
necessary, please follow these guidelines and
take Figure 2 for references.
1) Place the following components as close to
the MP7740 as possible:
Bootstrap Cap
CBS is used to supply the gate drive current to the
internal high-side MOSFET. Place CBS as close
to pins 5 and 7 as possible.
Power Supply Bypass
CBYP carries the transient current for the switching
power stage. To prevent overstressing of the
MP7740 and excessive noise at the output, place
CBYP as close to pins 6 (VDD) and 8 (PGND) as
possible.
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MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
Output Catch Diodes
DSH and DSL carry the current over the dead-time
while the MOSFET switches are off. Place the
diodes as close to the MP7740 as possible.
Timing Capacitors
CINT is used to set the amplifier switching
frequencies and are typically on the order of a
few nF. Place CINT as close to pins 1 and 2 as
possible to reduce distortion and noise.
Reference Bypass Capacitors
CR filters the ½ VDD reference voltages. Place CR
as close to the IC as possible to improve power
supply rejection and reduce distortion and noise
at the output.
2) The Inductor-Capacitor (LC) filter converts the
pulse train at SW to the output voltage that drives
the speaker. Please keep the filter capacitor
close to the inductor.
3) When laying out the PCB, use two separate
ground planes, analog ground (AGND) and
power ground (PGND), and connect the two
grounds together at a single point (usually
around the bulk bypass capacitor) to prevent
noise injection into the amplifier input to reduce
distortion.
4) Keep the sensitive feedback signal trace on
the input side and shield the trace with the AGND
plane. Make sure that any traces carrying the
switch node (SW) voltages are separated far
from any input signal traces. If it is required to run
the SW trace near the input, shield the input with
a ground plane between the traces. If multiple
amplifiers are used on a single board, make sure
that each channel is physically separated to
prevent crosstalk. Make sure that all inductors
used on a single circuit board have the same
orientation.
MP7740 Rev. 0.9
9/22/2009
If multiple amplifiers are used on a single board,
make sure that the power supply is routed from
the source to each channel individually, not
serially. This prevents channel-to-channel
coupling through the power supply input.
Electro-Magnetic Interference (EMI)
Considerations
Due to the switching nature of the Class D
amplifier, care must be taken to minimize the
effects of electromagnetic interference from the
amplifier. However, with proper component
selection and careful attention to circuit layout,
the effects of the EMI due to the amplifier
switching can be minimized.
The power inductors are a potential source of
radiated emissions. For the best EMI
performance, use toroidal inductors, since the
magnetic field is well contained inside the core.
However toroidal inductors can be expensive to
wind. For a more economical solution, use
shielded gapped ferrite or shielded ferrite bobbin
core inductors. These inductors typically do not
contain the field as well toroidal inductors, but
usually can achieve a better balance of good EMI
performance with low cost.
The size of high-current loops that carry rapidly
changing currents needs to be minimized. To do
this, make sure that the VDD bypass capacitors
are as close to the MP7740 as possible.
Nodes that carry rapidly changing voltage, such
as SW, need to be made as small as possible. If
sensitive traces run near a trace connected to
SW, place a ground shield between the traces.
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10
MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
TYPICAL APPLICATION CIRCUIT
VDD
RRH
4
OFF ON
1
CINT
5.6nF
2
CR
RRL
3
EN
VDD
PIN
PGND
MP7740
NIN
BS
AGND
SW
CVDDBYP
6
CBYP
8
5
CBS
7
DSL
(Optional) (8)
RFB
AUDIO
INPUT
CIN
CFB
RIN
22pF
LF
COUT
CF
OUTPUT
Figure 1— Mono Typical Application Circuit
AGND
PGND
CVDDBYP
AGND
PGND
Feedback
signal
CFB
RFB
CF
RRL
(8)
(Optional)
RRH
CR
CINT
1
PIN
PGND
8
2
NIN
SW
7
3
AGND
VDD
6
4
EN
BS
5
LF
DSL
CBYP
CBS
MP7740
Top
Bottom
Figure 2—Reference PCB Layout
Notes:
8) Schottky diode DSL only be required for short circuit protection. Detailed see SHORT CIRCUIT/OVERLOAD PROTECTION section in
Operation Information.
MP7740 Rev. 0.9
9/22/2009
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MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2009 MPS. All Rights Reserved.
11
MP7740 – 15W CLASS D MONO SINGLE ENDED AUDIO AMPLIFIER
PACKAGE INFORMATION
SOIC8E (EXPOSED PAD)
0.189(4.80)
0.197(5.00)
0.124(3.15)
0.136(3.45)
8
5
0.150(3.80)
0.157(4.00)
PIN 1 ID
1
0.228(5.80)
0.244(6.20)
0.089(2.26)
0.101(2.56)
4
TOP VIEW
BOTTOM VIEW
SEE DETAIL "A"
0.051(1.30)
0.067(1.70)
SEATING PLANE
0.000(0.00)
0.006(0.15)
0.013(0.33)
0.020(0.51)
0.0075(0.19)
0.0098(0.25)
SIDE VIEW
0.050(1.27)
BSC
FRONT VIEW
0.010(0.25)
x 45o
0.020(0.50)
GAUGE PLANE
0.010(0.25) BSC
0.050(1.27)
0.024(0.61)
0o-8o
0.016(0.41)
0.050(1.27)
0.063(1.60)
DETAIL "A"
0.103(2.62)
0.138(3.51)
RECOMMENDED LAND PATTERN
0.213(5.40)
NOTE:
1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN
BRACKET IS IN MILLIMETERS.
2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH,
PROTRUSIONS OR GATE BURRS.
3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH
OR PROTRUSIONS.
4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING)
SHALL BE 0.004" INCHES MAX.
5) DRAWING CONFORMS TO JEDEC MS-012, VARIATION BA.
6) DRAWING IS NOT TO SCALE.
NOTICE: The information in this document is subject to change without notice. Please contact MPS for current specifications.
Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS
products into any application. MPS will not assume any legal responsibility for any said applications.
MP7740 Rev. 0.9
9/22/2009
www.MonolithicPower.com
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2009 MPS. All Rights Reserved.
12