MP7752
18V, 2x15W Stereo BTL, Fixed Frequency,
Inductorless Class-D Audio Amplifier
The Future of Analog IC Technology
DESCRIPTION
FEATURES
The MP7752 is an analog input inductorless
class-D audio amplifier, which drives stereo
speakers in bridge-tied-load configuration. It is
a fully integrated audio amplifier, which reduces
solution size dramatically. It integrates 240mΩ
power MOSFETs and short-circuit protection
circuits, and it features start-up/shutdown pop
elimination and advanced EMI performance.
Also, it is inductorless while passing the EMC
test.
The MP7752 utilizes a stereo BTL structure
capable of delivering 15W per channel into 8Ω
speakers with a 16V power supply. MPS
class-D audio amplifiers exhibit the high fidelity
of class-AB amplifiers at high efficiency.
The MP7752 includes an internal circuit which
allows the system to shut down automatically
after the absence of the audio signal is detected.
This feature is used for energy-using products
and battery operated applications.
Also, it has an adjustable power limit function.
The PLIMIT circuit sets a limit on the output
peak-to-peak voltage. This is done by limiting
the duty cycle to a fixed maximum value. This
limit can be thought of as a "virtual" voltage rail,
which is lower than the supply connected to
PVCC.
The MP7752 is available in a TSSOP-28 EP
package.
MP7752 Rev. 1.01
5/27/2016
5V to 18V Operation from a Single Supply
±5A Peak Current Output
Output Power:
9.5W/Channel at 12V, 8Ω Load, 10%THD
15W/Channel at 16V, 8Ω Load, 10%THD
90% Efficiency with 8Ω Load, 10%THD,
1kHz, 12V Supply Voltage
240mΩ Power MOSFETs
Start-UP/Shutdown Pop Elimination
Short-Circuit Protection Circuits
Inductorless Topology
Advanced EMI performance
All Switches Current Limited
Internal Under-Voltage Protection
Internal Thermal Protection
TSSOP-28 EP Package
Adjustable Power Limiter
Automatic Shutdown with Zero Input Signal
Detection
Fault Output Flag
APPLICATIONS
TV
DVD Receiver
Active Speaker
All MPS parts are lead-free, halogen-free, and adhere to the RoHS directive. For
MPS green status, please visit the MPS website under Quality Assurance.
“MPS” and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.
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© 2016 MPS. All Rights Reserved.
1
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
TYPICAL APPLICATION
Audio Input L +
Cin
Audio Input L -
Cin
Input Absence
IN1A
IN1B
InAbsence
PVCC
5 to 18V
BST1A
SW1A
FB
OUT1A
FB
OUT1B
FB
OUT2A
FB
OUT2B
CAP_D
CD
BST1B
Speaker L
Power Limit
PLIMIT
IN2A
Audio Input R +
Cin
BST2A
Audio Input R -
IN2B
Cin
Gain control
Enable
SW1B
SW2A
Gain 0
Gain 1
BST2B
EN
SW2B
Fault Flag
MP7752 Rev. 1.01
5/27/2016
Speaker R
FAULT/
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2
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
ORDERING INFORMATION
Part Number*
MP7752GF
Package
TSSOP-28 EP
Top Marking
See Blow
* For Tape & Reel, add suffix –Z (e.g. MP7752GF–Z)
TOP MARKING
MPS: MPS prefix:
YY: year code;
WW: week code:
MP7752: part number;
LLLLLLLLL: lot number;
PACKAGE REFERENCE
TSSOP-28 EP
MP7752 Rev. 1.01
5/27/2016
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3
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
ABSOLUTE MAXIMUM RATINGS (1)
Thermal Resistance
Supply Voltage VCC ......................–0.3V to +20V
VSW ............................................ –1V to VCC + 1V
VEN, V/FAULT, VGAIN, VInAbsence – 0.3V to VCC + 0.3V
BS Voltage VBST ............. VSW – 0.3V to VSW + 6V
VPLIMIT ............................. – 0.3V to VAVCC + 0.3V
VINXX ............................................. – 0.3V to 6.5V
AGND to PGND ..........................–0.3V to +0.3V
(2)
Continuous Power Dissipation (TA = +25°C)
………………………………………………...3.9W
Junction Temperature ...............................150°C
Lead Temperature ....................................260°C
Storage Temperature.............. –65C to +150C
TSSOP-28 EP .…… .… .…. .…32
Recommended Operating Conditions
(3)
(4)
θJA θJC
6
°C/W
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 VIN ..............................5V to 18V
Operating Junction Temp. (TJ). -40°C to +125°C
MP7752 Rev. 1.01
5/27/2016
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4
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
ELECTRICAL CHARACTERISTICS (5, 6)
VCC = 18V, VEN = 5V, TJ = -40C to 125C, unless otherwise noted.
Parameters
Standby Current
Quiescent Current
Output Offset Voltage
SW On Resistance
Symbol Condition
IQSTBY VEN = 0V,NIN=PIN=Float
IQ
VEN = 5V, no load, no LC filter
VI = 0 V, Gain = 36 dB,
VOS
Tj = 25C
RdsON
Short Circuit Current
Closed Loop Gain
G
EN Enable Threshold Voltage
EN Enable Input Current
Under Voltage Protection
IO = 500mA, TJ = 25C
Sourcing and Sinking,
TJ = 25C
GAIN0 = L, GAIN1 = L
GAIN0 = H, GAIN1 = L
GAIN0 = L, GAIN1 = H
GAIN0 = H, GAIN1 = H
VEN Rising
VEN Falling
VEN = 5V
VUVP Rising
VUVP Falling
AVCC Operating Voltage
VDR Operating Voltage
VINN/INP Common Mode Voltage
Thermal Shutdown Trip Point
VGAIN Falling
Typ
130
20
Max
200
40
Units
µA
mA
20
65
mV
0.24
Ω
4
5
6
19
25
31
35
20
26
32
36
1.3
0.9
12
4.6
4.3
5.5
5.5
2.5
21
27
33
37
2.0
6
6
2.7
V
V
µA
V
V
V
V
V
1.6
2
V
360
8
V
ms
us
kHz
mV
0.4
4
5
5
2.3
VGAIN Rising
GAIN0/GAIN1 Threshold
Turn-on Time
Turn-off Time
Switching frequency
Input signal absence sensitivity
Min
0.6
tON
tOFF
260
2
TJ Rising
Thermal Shutdown Hysteresis
1.1
13
0.2
325
5
25
5
A
dB
150
C
20
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.
MP7752 Rev. 1.01
5/27/2016
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5
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
OPERATING SPECIFICATIONS (7)
Circuit of figure 5, VCC = 18V, Gain=20dB, VEN = 5V, RLOAD = 8Ω+66uH, TA = +25C, unless
otherwise noted.
Parameters
Symbol Condition
f = 1kHz, THD+N = 10%, VCC = 18V
f = 1kHz, THD+N = 10%, VCC = 16V
f = 1kHz, THD+N = 10%, VCC = 12V
POUT = 5W, f = 1kHz, VCC = 12V
POUT = 15W, f = 1kHz, VCC = 18V
Power Output
THD+ Noise
Min
Typ
20
15
9.5
0.5
0.5
Max
Units
W
%
%
Efficiency
POUT = 9.5W + 9.5W, THD+N = 10%,
VCC = 12 V, 1kHz, RLOAD = 8Ω
90
%
Deadtime
Cross Talk
Noise Floor
Signal-to-noise ratio
IO=0.5A
VO = 1 Vrms, f = 217Hz
A-Weighted, 22 Hz to 22 kHz
f = 1kHz, THD+N = 1%, A-Weighted
40
-110
115
100
nS
dB
μV
dB
Power Supply Rejection
VRIPPLE=300mVPP,
Inputs ac-coupled
to AGND
f = 1kHz
-60
dB
f = 217Hz
-70
dB
Notes:
7) Operating Specifications are for the IC in Typical Application circuit. Not production tested.
MP7752 Rev. 1.01
5/27/2016
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6
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
TYPICAL PERFORMANCE CHARACTERISTICS
VCC = 12V, GAIN = 20dB, f = 1kHz, TA = 25°C, unless otherwise noted.
MP7752 Rev. 1.01
5/27/2016
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MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VCC = 12V, GAIN = 20dB, f = 1kHz, TA = 25°C, unless otherwise noted.
MP7752 Rev. 1.01
5/27/2016
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8
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VCC = 12V, GAIN = 20dB, f = 1kHz, TA = 25°C, unless otherwise noted.
MP7752 Rev. 1.01
5/27/2016
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9
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VCC = 12V, GAIN = 20dB, f = 1kHz, TA = 25°C, unless otherwise noted.
MP7752 Rev. 1.01
5/27/2016
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10
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
TYPICAL PERFORMANCE CHARACTERISTICS (continued)
VCC = 12V, GAIN = 20dB, f = 1kHz, TA = 25°C, unless otherwise noted.
20
5
5
1
POUT = 5W
1
+4
10kHz
1kHz
POUT = 2.5W
0.1
+2
20Hz
GAIN (dB)
20
0.1
POUT = 1W
0.01
+0
-2
-4
-6
0.01
-8
0.001
20
100
500 1k 2k 5k10k 20k
Frequency (Hz)
0.001
60m 200m
-20
dB
60
50
-60
40
-80
-100
30
20
-100
Right to Left
-120
2k 4k 6k 8k 10k12k14k16k18k20k
-120
20
100
1k 2k
Frequency (Hz)
Frequency (Hz)
60k
70
Left to Right
-80
1k 2k
10k
Frequency (Hz)
80
-40
-60
100
90
-20
-40
-10
20
100
+0 T T T
+0
dBV
1 2
5 10 2030
POUT (W)
10k 20k
10
0
0
3
6
9
12
15
POUT (W)
18
16
14
THD=10%
POUT (W)
12
10
8
THD=1%
6
4
2
0
5
7
9
11
13
15
VDD (V)
MP7752 Rev. 1.01
5/27/2016
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11
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
PIN FUNCTIONS
Pin #
Name
1
EN
2
3
4
5
6
7
8
9
10
11
12
13
14
15, 16
17
Description
Enable input. Drive EN high to turn on the Amplifier 1A/1B/2A/2B, low to turn them off.
Fault Output. A low output at FAULT indicates that the IC has detected an over
temperature or over current condition. This output is open drain.
IN1A
Positive audio input for channel 1. Biased at 2.5V.
IN1B
Negative audio input for channel 1. Biased at 2.5V.
GAIN0
Gain selection bit.
GAIN1
Gain selection bit.
AVCC
Internal analog reference, 5.5V, need connect a bypass capacitor from AVCC to AGND.
AGND
Analog ground.
Gate Drive Supply Bypass. VDR powers the internal circuitry, internal MOSFET gate
VDR
drive. Bypass VDR to AGND with a 0.1μF to 10μF capacitor.
Power limit and anti-clipping feature control.
PLIMIT
Connect a resistor divider from AVCC to GND to set power limit. Connect directly to
AVCC for no power limit.
IN2B
Negative audio input for channel 2. Biased at 2.5V.
IN2A
Positive audio input for channel 2. Biased at 2.5V.
InAbsence Open drain output used to report the input signal absence.
Delay Time control for input signal absence report function. This holding time can be
Cap_D
adjusted with external capacitor. Connect this pin to AGND to disable automatic shutdown
with zero signal input function.
Power supply input for channel 2. Bypass PVCC2 to PGND2 with a 1μF X7R capacitor (in
PVCC2
addition to the main bulk capacitor), placed close to the PVCC2 and PGND2 pins.
High-side MOSFET bootstrap input for Amplifier 2A. A capacitor from BST2A to SW2A
BST2A
supplies the gate drive current to the internal high-side MOSFET.
/FAULT
18
SW2A
19
PGND2
20
SW2B
21
BST2B
22
BST1B
23
SW1B
24
25
PGND1
SW1A
26
BST1A
27, 28
PVCC1
MP7752 Rev. 1.01
5/27/2016
Switched power output for Amplifier 2A (the positive output of channel 2).
Power ground for Amplifier 2A/2B.
Switched power output for Amplifier 2B (the negative output of channel 2).
High-side MOSFET bootstrap input for Amplifier 2B. A capacitor from BST2B to SW2B
supplies the gate drive current to the internal high-side MOSFET.
High-side MOSFET bootstrap input for Amplifier 1B. A capacitor from BST1B to SW1B
supplies the gate drive current to the internal high-side MOSFET.
Switched power output for Amplifier 1B (the negative output of channel 1).
Power ground for Amplifier 1A/1B.
Switched power output for Amplifier 1A (the positive output of channel 1).
High-side MOSFET bootstrap input for Amplifier 1A. A capacitor from BST1A to SW1A
supplies the gate drive current to the internal high-side MOSFET.
Power supply input for channel 1. Bypass PVCC1 to PGND1 with a 1μF X7R capacitor (in
addition to the main bulk capacitor), placed close to the PVCC1 and PGND1 pins.
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MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
FUNCTIONAL BLOCK DIAGRAM
Internal
BST1A
R3
VDD
Comparator
C
Cin
R1
Ri
Level
detector
SW1A
Gate
Drive
FB
OUT1A
FB
OUT1B
R2
FDA
FDA
Power
Limiter
BST1B
VDD
C
Cin
R1
Ri
Speaker L
R2
Comparator
Gain
Selection
Gain=(R1/Ri)*(R3/R2)
Gate
Drive
SW1B
Delay time
R3
Triangular
Generator
Shutdown
OCP
OTP
UVP
Power Limit
Reference
Functional Block Diagram (only one channel)
MP7752 Rev. 1.01
5/27/2016
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MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
OPERATION
The MP7752 is a fully integrated Class D stereo
BTL audio amplifier. 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 MP7752 includes a delay circuit which
allows the IC continues to hold the flag after the
absence of the audio signal. This holding time
can be adjusted with external capacitor.
1.
The amplifier has fully differential outputs and
inputs. The differential input is useful to minimize
the common-mode noise (any noise that appears
on both input lines of the channel). This device
can still be used with a single-ended input.
The MP7752 includes eight high-power
MOSFETs wherein for each half-bridge channel
the output driver stage uses two N-Channel
MOSFETs to deliver the pulses to the magnetic
bead and capacitor 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 OUTxx and BSTxx pins. While the
output is driven low, the bootstrap capacitor is
charged from power supply through an internal
circuit. The gate of the high-side MOSFET is
driven high from the voltage at Bootstrap Supply,
forcing the MOSFET gate to a voltage higher
than power supply voltage and allowing the
MOSFET to fully turn on, reducing power loss in
the amplifier.
The gain of the MP7752 is set by the input
terminals, GAIN0 and GAIN1. The actual gain
settings are controlled by ratios of the input and
feedback resistors
Enable Function
The MP7752 EN input is an active high enable
control. To enable the MP7752, drive EN with a
2.0V or higher voltage. To disable the amplifier,
drive it below 0.4V. While the MP7752 is disabled,
the PVCC operating current is around 250μA and
the output driver MOSFETs are turned off.
The input absence flag will be high initially
when power on. After device enabled, the
internal circuit start to detect the input signal.
MP7752 will then hold the output report and
normal operation for a delay time which can
be adjusted by the Capacitor value @ pin 14.
Then MP7752 will turn off the all MOSFETs
and pull low the input absence output, until
the input signal detected again.
Figure 1a: enable on with no signal detected
2.
The input absence flag output will be or
maintain high when input signal is detected.
The delay circuit will only be activated when
the input signal absence. MP7752 will then
hold the output report for a delay time which
can be adjusted by the Capacitor value @
pin 14. Then MP7752 will turn off the all
MOSFETs and pull low the input absence
output, until the input signal detected again.
Input signal Absence detect
The MP7752 includes an internal circuit which
allows the system automatic shutdown after the
absence of the audio signal. This feature is used
for energy-using products and for battery
operated applications.
MP7752 Rev. 1.01
5/27/2016
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14
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
given maximum input voltage and speaker
impedance.
POUT
RL
VP
RL 2 R S
2 RL
2
for unclipped power
Where:
RS is the total output series resistance (including
Rdson and the resistance of output filter.
Figure 1b: enable on with audio signal present
RL is the load resistance.
Adjustable Power Limit
VP is the peak amplifier of the output voltage.
Power limit and anti-clipping feature control. The
voltage at pin 10 can used to limit the power to
levels below that which is possible based on the
supply rail.
Connect a resistor divider from AVCC to GND to
set power limit. Connect directly to AVCC for no
power limit.
VP = 9 x PLIMIT voltage if 8 x PLIMIT < PVCC
And
An external reference may also be used if tighter
tolerance is required. Also add a 1μF capacitor
from pin 10 to ground.
Input signal=1Vrms
Plimit=1.74V=11.24W
Plimit=1.44V=10W
Plimit=0.8V=5W
Figure 2. PLIMT Circuit Operation
The PLIMIT circuit sets a limit on the output
peak-to-peak voltage. The limiting is done by
limiting the duty cycle to fixed maximum value.
This limit can be thought of as a "virtual" voltage
rail which is lower than the supply connected to
PVCC. This "virtual" rail is 9 times the voltage at
the PLIMIT pin. This output voltage can be used
to calculate the maximum output power for a
MP7752 Rev. 1.01
5/27/2016
POUT @10%THD 1.25 unclipped POUT
Table 2: Power Limit Typical Operation
Output
Voltage
(Vp-p)
Output Power
(10% THD)
0.80V
14.9
5.0W
0.80V
14.9
5.0W
1.44V
23.6
10.0W
1.44V
23.6
10.0W
Test
PLIMIT
Condition Voltage
VDD=12V,
Vin=1Vrms,
Load=8Ω,
Gain=20dB
VDD=16V,
Vin=1Vrms,
Load=8Ω,
Gain=20dB
VDD=16V,
Vin=1Vrms,
Load=8Ω,
Gain=20dB
VDD=18V,
Vin=1Vrms,
Load=8Ω,
Gain=20dB
Gain Setting
The gain of the MP7752 is set by the input
terminals, GAIN0 and GAIN1. The actual gain
settings are controlled by ratios of the internal
input and feedback resistors, details please see
the below table.
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MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
Table 2: Gain Setting
GAIN0 GAIN1
0
1
0
1
0
0
1
1
Typ. GAIN Typ. Input Impedance
(dB)
(kΩ)
20
26
32
36
75
50
30
20
A fault on any channel will cause the FAULTB pin
to pull low. A fault on either channel will cause
the all outputs to go into high impedance. When
the fault goes away, the MP7752 will resume
normal operation.
Over-Temperature Shutdown
Thermal monitoring is also integrated into the
MP7752. If the die temperature rises above
150°C, all switches turn off. The temperature
must fall below 130°C before normal operation
resumes, with the same power-up sequence
used to prevent popping noise.
Short Circuit Performance
The MP7752 has internal overload and short
circuit protection. The currents in both the highside and low-side MOSFETs are measured.
Upon detection of short circuit, all MOSFETs of
the over current full bridge channel will go into
high impedance for a fixed duration before
resuming normal operation. After the fixed
duration and the short circuit condition is
removed, the MP7752 will restart with the start
up sequence that is used for normal starting to
prevent a pop from occurring.
Figure 3: Fault Timing Chart
Fault Output
The MP7752 includes an open drain, active low
fault indicator output on the /FAULT pin. A fault
triggers if either the current limit or thermal
shutdown is tripped.
MP7752 Rev. 1.01
5/27/2016
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16
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
APPLICATION INFORMATION
COMPONENT SELECTION
Delay time for input signal absence report
The Recovery time is defined as follows.
Tdelay 1.6 108 CR sec
Choosing the Output EMI Filter
The magnetic bead-capacitor filter converts the
pulses at SW to the output voltage that drives
the speaker. Both PVCC line and output current
flow needed magnetic beads to prevent large
radiation from high slew-rate pulse. The larger
impedance of the magnetic bead, the better
EMI performance can be approach.
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 two smaller 1μF and 1nF ceramic
capacitors at the MP7752 VCC supply pins.
PCB Layout
Circuit layout is critical for optimal performance,
low output distortion, and noise. Duplicate the
EVB layout for best results. For layout changes,
follow these guidelines.
1) Place the following components as close to
the MP7752 as possible:
Input Coupling Capacitor
Bootstrap Capacitors
The input coupling capacitor transmits the AC
signal from the source to the MP7752 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:
CBS supply the gate drive current to the internal
HS-FET. Place CBS as close to BST pin and SW
pin as possible.
fIN
1
2 RIN CIN
The impedance of the input resister is different
with the different gain setting. At the same gain
setting, the input impedance from part-to-part
may shift by ±20% due to shifts in the actual
resistance of the input resistors. But please
note that the gain variation from part-to-part is
small.
For design purposes, the input network should
be designed assuming an input impedance of
16 kΩ, which is the absolute minimum input
impedance of the MP7752. At the lower gain
settings, the input impedance could increase as
high as 90 kΩ.
Power Source
For maximum output power, the amplifier circuit
requires a regulated external power source. A
high power-supply voltage can deliver more
power to a given load resistance, but a powersource voltage exceeding the maximum voltage
of 18V can damage the MP7752. The
MP7752’s power supply rejection is excellent,
though power-supply noise can pass to the
MP7752 Rev. 1.01
5/27/2016
Power Supply Bypass Capacitors
CBYP carry the transient current for the switching
power stage. To avoid overstressing the
MP7752 and excessive output noise, place
CBYP as close to the PVCC pins as possible.
2) The magnetic bead-Capacitor filter converts
the pulse train at SW to the output voltage that
drives the speaker. Please keep the filter
capacitor close to the magnetic bead.
3) Make sure that any traces carrying the switch
node (SW) voltages are routed far from any
input signal traces. If the trace must run near
the SW trace near the input, shield the input
with a ground plane between the traces.
Physically separate each channel to prevent
crosstalk.
Route each power supply from the source to
each channel individually, not serially. This
prevents channel-to-channel coupling through
the power supply input.
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MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
17
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
Electro-Magnetic Interference (EMI)
Considerations
tested work well in series with PVCC and four
SW outputs.
Due to the switching nature of Class D
amplifiers, care must be taken to minimize the
effects of electromagnetic interference from the
amplifier. However, proper component selection
and careful attention to circuit layout can
minimize the effects of the EMI due to the
amplifier switching.
The size of high-current loops that carry rapidly
changing currents must be minimized: Make
sure that the VCC bypass capacitors are as
close to the MP7752 as possible.
The magnetic beads are used for blocking
radiated emissions from SW nodes. For the
best EMI performance, use high current and
high impedance magnetic bead. muRata
NFZ2M series CLASS D EMI filter has been
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.
MP7752 EVB passed CISPR22 CLASS B
standard with stereo full power output.
Figure 4: EMI Test Data of MP7752 EVB
Test Condition: 10 meter EMI chamber, 1.2 meter twist speaker cable, MP7752 EVB stereo test.
VDD=12V, LOAD=8ohm+66uH, POUT=9.5W X 2, 1 kHz Signal.
MP7752 Rev. 1.01
5/27/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
18
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
TYPICAL APPLICATION CIRCUITS
Figure 5: Typical Application Circuit
MP7752 Rev. 1.01
5/27/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
19
MP7752 – 18V, 2X15W STEREO FIX FREQUENCY INDUCTORLESS BTL CLASS D AUDIO AMPLIFIER
PACKAGE INFORMATION
TSSOP-28 EP
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.
MP7752 Rev. 1.01
5/27/2016
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
20
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