PAM PAM8012AZN

PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Key Features
General Description
n 1.0W/2.0W@<1% THD Output with a 8 Ω / 4 Ω
The PAM8012 is a 2.0W mono filterless class-D
amplifier with high PSRR and differential input that
reduce noise.
n
n
n
n
n
n
n
n
Load at 5V Supply
Maximum Output Power Can Be Set by One
External Resistor
Minimized ON/OFF Pop Noise
Superior Low Noise
High PSRR
Supply Voltage from 2.5V to 5.5 V
Auto Recovering Short Circuit Protection
Over Temperature Protection
9 Ball, 1.3mm x 1.3mm, 0.4mm Pitch WCSP and
eMSOP10 Packages
Features like 90% efficiency and small PCB area
make the PAM8012 Class-D amplifier ideal for
cellular handsets. The filterless architecture
requires no external output filter, fewer external
components, less PCB area and lower system
costs, and simplifies application design.
Applications
The PAM8012 features anti-saturation function
which detect output signal clip due to the over
input level and keep the output non-saturation
automatically to get the excellent sound quality.
n
n
n
The maximum output power without clip can be set
by one resistor at PL pin that to prevent the
speaker to be damaged..
Wireless or Cellular Handsets and PDAs
Portable Navigation Devices
General Portable Audio Devices
The PAM8012 features short circuit protection and
over temperature protection.
The PAM8012 is available in tiny WCSP9 (1.3mm
x 1.3mm) and eMSOP10 packages.
Typical Application Circuit
VDD
1 μF
10μF
VDD
0.1 μF
IN+
Input
0.1 μF
IN-
OUT+
ON
EN
OFF
PAM8012
RPL
PL
1 μF
OUT-
1 μF
VREF
GND
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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1
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Block Diagram
VDD
IN+
Rin
Rf
PWM
Modulator
Rin
IN-
+
Rf
Gate
Drive
OUT+
Gate
Drive
OUT-
Anti-Sat
EN
Bias
PL
Power
Limit
SCP
OTP
UVLO
Startup
Protection
OSC
VREF
VREF
GND
Pin Configuration & Marking Information
9 Ball 0.4mm pitch WCSP
Top View of PCB
OUT+
OUT-
GND
A1
A2
A3
VDD
EN
PL
B1
B2
B3
VREF
IN+
IN-
C1
C2
C3
9 Ball 0.4mm pitch WCSP
Top View of Marking
BI
YW
BI: Product Code of PAM8012
Y: Year
W: Week
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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2
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Top View
eMSOP10
PGND 1
10
OUT+
OUT- 2
9
VDD
PL 3
8
EN
IN- 4
7
VREF
IN+ 5
6
AGND
X: Internal Code
Y: Year
W: Week
Absolute Maximum Ratings
These are stress ratings only and functional operation is not implied . Exposure to absolute
maximum ratings for prolonged time periods may affect device reliability . All voltages are with
respect to ground.
Supply Voltage, VDD...................................6.0V
Input Voltage,IN+,IN-...............-0.3V to VDD+0.3V
Minimum load resistance, R L......................3.2 Ω
Storage Temperature.....................-65°C to 150 °C
Maximum Junction Temperature..................150°C
Soldering Temperature....................260°C,10 sec
Recommended Operating Conditions
Supply voltage Range........................ 2.5V to 5.5V
Ambient Temperature Range............-40 °C to 85 °C
Junction Temperature Range......... -40°C to 125°C
Thermal Information
Parameter
Symbol
Thermal Resistance (Junction to ambient)
θJA
Thermal Resistance (Junction to case)
Package
Maximum
WCSP9 1.3x1.3
100
eMSOP10
60
WCSP9 1.3x1.3
40
eMSOP10
30
Unit
°C/W
θJC
°C/W
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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3
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Electrical Characteristic
T A=25 °C, VDD=5.0V, RL =8 Ω , unless otherwise noted.
Symbol
VDD
Po
Pa ra me te r
Test Conditions
Supply V oltage
Output Power
Total Harmonic Distortion Plus
THD+N
Noise
RPL=110K Ω,f=1kHz, R=4Ω
VDD=5.0V
2.0
RPL=110K Ω,f=1kHz, R=8Ω
VDD=5.0V
1.0
SNR
Vn
Signal to Noise Ratio
THD=1% , f=1KHz
Output Noise
Cin=0.1uF, Inputs acgrounded
RL=8Ω
UNIT
5.5
V
W
%
0.08
VDD=5.0V ,P o=1.0W,R=8Ω
f=217Hz, Inputs ac-grounded
with Cin=0.1µF
MAX
0.08
f=1kHz
VDD=3.6V ,P o=1.0W,R=4Ω
VDD=3.6V ,P o=0.5W,R=8Ω
AC Power Supply Ripple
Rejection
TYP
2.5
VDD=5.0V ,P o=2.0W,R=4Ω
PSRR
MIM
0.08
f=1kHz
%
0.08
VDD=5.0V
-75
VDD=3.6V
-75
VDD=5.0V
95
VDD=3.6V
95
No A-weighting
60
A -wei ghting
40
dB
µV
90
η
Peak E fficiency
IQ
Quiescent Current
VEN=5.0V,VDD=5.0V,PL=0V
No Load
Isd
Shutdown Current
VDD=2.5V to 5.5V ,V EN=0V
No Load
|VOS|
Offset Voltage
VDD=5V
RIN
Input Resistor
VDD=5V
31
KΩ
GV
Closed Loop Gain
VDD=5V
18
dB
f SW
Switching Frequency
VDD=5V
250
K Hz
TON
Turn-on Time
VDD=5V
45
mS
OTP
Over Temperature P rotecti on
VDD=5V
No Load
150
℃
OTH
Over Temperature Hysterisis
VDD=5V
No Load
40
℃
VENH
High-level EN voltage
VDD=5V
VENL
Low-level EN voltage
VDD=5V
Maximum Attenuation Range
Anti-saturation Active,from +18dB to -8dB
AR
f=1kHz
RL=4Ω
%
87
4.2
-20
mA
1
uA
20
mV
1.4
V
0.4
26
V
dB
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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4
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Typical Operating Characteristics
T A=25 °C, V DD=5V, unless otherwise noted.
1. THD+N VS Output Power
2. THD+N VS Output Power
20
20
RL =8 Ω
10
5
Vin=5V
5
2
%
0.5
Vin=5V
2
Vin=4.2V
1
%
R L=4 Ω
10
Vin=4.2V
1
0.5
Vin=3.6V
0.2
Vin=3.6V
0.2
0.1
0.1
0.04
1m
2m
5m
10m
20m
50m
100m
200m
500m
1
0.05
1m
2
2m
5m
10m
20m
50m
W
3. THD+N VS Frequency
500m
1
2
4
4. THD+N VS Frequency
10
10
RL =8 Ω
5
100m 200m
W
5
2
RL =4 Ω
2
1
1
Po=1W
0.5
Po=1W
0. 5
%
Po=0.5W
%
Po=0.5W
0.2
0. 2
0.1
0. 1
0.05
0.0 5
Po=0.3W
Po=0.3W
0.02
0.0 2
0.01
0.007
20
50
100
200
500
1k
2k
5k
10k
0.0 1
20
20k
50
100
Hz
500
1k
2k
5k
10k
20k
Hz
5. Frequency Response
6. Frequency VS Supply Voltage
255
+ 20
Cin=1uF
+ 19
200
253
+ 18
+ 17
251
+ 16
+ 15
249
Cin=0.47uF
+ 14
d
B
r
+ 13
A
+ 11
247
245
+ 12
+ 10
243
Cin=0.1uF
+ 9
241
+ 8
239
+ 7
+ 6
237
+ 5
+ 4
20
50
100
200
500
1k
2k
5k
10k
20 k
235
50 k
Hz
2.0
3.0
4.0
5.0
6.0
Supply Voltage(V)
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Typical Operating Characteristics
T A=25 °C, V DD=5V, unless otherwise noted.
7. Efficiency VS Output Power
8. Efficiency VS Output Power
100
100
RL =8 Ω
90
R L=4 Ω
90
80
80
70
70
60
60
50
50
40
40
30
30
20
20
10
10
0
0
0
0.5
1
Out put P ower(W)
1. 5
2
0
0. 5
9. PSRR VS Frequency
+0
TT TT TT TT
R L=8 Ω
T TT
- 10
-20
- 20
-30
- 30
-40
d
B
1. 5
2
2. 5
Ou tp ut P ower(W )
3
3. 5
10. PSRR VS Frequency
+0
-10
1
T
RL =4 Ω
- 40
d
B
-50
- 50
-60
- 60
-70
- 70
-80
- 80
-90
- 90
- 100
- 100
20
50
100
200
500
1k
2k
5k
10k
20
20 k
50
100
200
500
2k
5k
10 k
20k
12. R PL VS Output Power
11. Rdson VS Load Current
300
1. 2
250
1
200
0. 8
150
0. 6
100
0. 4
Vin=4.2V
RL =8 Ω
0. 2
PMOS(mΩ)
50
1k
Hz
Hz
NMOS(mΩ)
0
0
0
500
1000
1500
0
2000
20
40
60
80
100
120
140
RPL(kΩ)
Load Current(mA)
Power Analog Microelectronics, Inc
06/2012 Rev1.3
www.poweranalog.com
6
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Test Setup for Performance Testing
PAM8012 Demo Board
Load
+OUT
Input
AP System One
Generator
AP
Low Pass
Filter
GND
-OUT
AP System Two
Analyzer
AUX-0025
VDD
Power Supply
Notes
1. The AP AUX-0025 low pass filter is necessary for class-D amplifier measurement with AP analyzer.
2. Two 33µH inductors are used in series with load resistor to emulate the small speaker for efficiency
measurement.
Application Information
Anti-saturation
The Anti-saturation feature provides continuous automatic gain adjustment to the amplifiier through an
internal circuit. This feature enhances the perceived audio loudness and at the same time prevents
speaker damage from occurring.
The Anti-saturation works by detecting the output. The gain changes depending on the supply voltage ,
and the attack and release time. The gain changes constantly as the audio signal increases and/or
decreases. The gain step size for the Anti-saturation is 0.4 dB. If the audio signal has near-constant
amplitude, the gain does not change. Table 1 shows the Anti-saturation variable description.
Table 1. PAM8012 Anti-saturation Variable Description
VARIABLE
Gain
DE SCRIP TI ON
V alue
The pre-set gain of the device when the Anti-saturation is inactive.
18dB
The fixed gain is also the initial gain when the device c omes out of
(Max imum)
shutdown mode or when the Anti-s aturation is disabled
Attack Time
The minimum time between two gain dec rements .
128uS
Release Time
The minimum time between two gain increments.
256mS
PL Terminal Function
The voltage value of PL sets the PAM8012 maximum output by an external resistor. Refer to t able 2 for
anti-saturation and power limit selection.
Table 2. PAM8012 Anti-saturation and Power Limit Variable Description
VDD
EN
VDD/2
0
PL: OFF
Anti-sat: OFF
PL: OFF
Anti-sat: OFF
Rpl
30K<Rpl<120K
PL: ON
Anti-sat: ON
PL: ON
Anti-sat: OFF
Open
PL: OFF
Anti-sat: ON
PL: ON
Anti-sat: OFF
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Application Information
Input Capacitors (Ci )
audio power amplifier is recommended.
In the typical application, an input capacitor, Ci,
is required to allow the amplifier to bias the input
signal to the proper DC level for optimum
operation. In this case, Ci and the minimum input
impedance Ri form is a high-pass filter with the
corner frequency determined in the follow
equation:
How to Reduce EMI
fc =
Most applications require a ferrite bead filter for
EMI elimination shown at Figure 1. The ferrite
filter reduces EMI around 1MHz and higher.
When selecting a ferrite bead, choose one with
high impedance at high frequencies, but low
impedance at low frequencies.
1
2pRiCi
Fe rrit e Be ad
It is important to consider the value of Ci as it
directly affects the low frequency performance of
the circuit. For example,the specification calls
for a flat bass response are down to 150Hz.
Equation is reconfigured as followed:
Ci =
OUT+
20 0p F
Fe rrit e Bea d
OUT-
1
2p Rifc
20 0p F
Figure 1: Ferrite Bead Filter to Reduce EMI
When input resistance variation is considered,
the Ci is 34nF, so one would likely choose a value
of 33nF. A further consideration for this capacitor
is the leakage path from the input source through
the input network (Ci , Ri + Rf ) to the load. This
leakage current creates a DC offset voltage at
the input to the amplifier that reduces useful
headroom, especially in high gain applications.
For this reason, a low-leakage tantalum or
ceramic capacitor is the best choice. When
polarized capacitors are used, the positive side
of the capacitor should face the amplifier input in
most applications as the DC level is held at V DD/2,
which is likely higher than the source DC level.
Please note that it is important to confirm the
capacitor polarity in the application.
Shutdown operation
In order to reduce power consumption while not
in use, the PAM8012 contains shutdown circuitry
that is used to turn off the amplifier’s bias
c ircuitr y. This shutdown featur e tur ns the
amplifier off when logic low is placed on the EN
pin. By switching the EN pin connected to GND,
the PAM8012 supply current draw will be
minimized in idle mode.
Short Circuit Protection (SCP)
The PAM8012 has short circuit protection
circuitry on the outputs to prevent the device
from damage when output-to-output shorts or
output-to-GND shorts occur. When a short circuit
o cc urs , the dev ice i mmed iatel y goe s into
shutdown state. Once the short is removed, the
device will be reactivated.
Decoupling Capacitor (C S )
The PAM8012 is a high-performance CMOS
audio amplifier that requires adequate power
supply decoupling to ensure the output total
harmonic distortion (THD) as low as possible.
Power supply decoupling also prevents the
oscillations causing by long lead length between
the amplifier and the speaker.
The optimum decoupling is achieved by using
two different types of capacitors that target on
different types of noise on the power supply
leads. For higher frequency transients, spikes, or
digital hash on the line, a good low equivalentseries-resistance (ESR) ceramic capacitor,
typically 1 μF, is placed as close as possible to
VDD pin for the best operation. For filtering lower
fr e q ue nc y n oi s e s i gn a ls , a l ar g e c e r am i c
c apacitor of 10μF or greater placed near the
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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8
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Over Temperature Protection (OTP)
Power Supply Line
Thermal protection on the PAM8012 prevents the
device from damage when the internal die
temperature exceeds 150°C. There is a 15 °C
tolerance on this trip point from device to device.
Once the die temperature exceeds the set point,
the device will enter the shutdown state and the
outputs are disabled. This is not a latched fault.
The thermal fault is cleared once the
temperature of the die decreased by 40°C . This
large hysteresis will prevent motor boating sound
well and the device begins normal operation at
this point with no external system interaction.
It is recommended that all the trace could be
routed as short and thick as possible. For the
power line layout, just imagine water stream, any
barricade placed in the trace (shown in figure 2)
could result in the bad performance of the
amplifier.
POP and Click Circuitry
Components Placement
The PAM8012 contains circuitry to minimize turnon and turn-off transients or “click and pops”,
where turn-on refers to either power supply turnon or device recover from shutdown mode. When
the device is turned on, the amplifiers are
internally muted. An internal current source
ramps up the internal reference voltage. The
device will remain in mute mode until the
reference voltage reach half supply voltage, 1/2
VDD. As soon as the reference voltage is stable,
the device will begin full operation. For the best
power-off pop performance, the amplifier should
be set in shutdown mode prior to removing the
power supply voltage.
Decoupling capacitors as previously described,
the high-frequency 1 μF decoupling capacitors
should be placed as close to the power supply
terminals VDD as possible. Large bulk power
supply decoupling capacitors (10 μF or greater)
should be placed near the PAM8012 on the VDD
terminal.
Figure 2: Power Line
Input resistors and capacitors need to be placed
very close to input pins.
Output filter - The ferrite EMI filter should be
placed as close to the output terminals as
possible for the best EMI performance, and the
capacitors used in the filters should be grounded
to system ground.
PCB Layout Guidelines
Grounding
It is recommended to use plane grounding. Noise
currents in the output power stage need to be
returned to output noise ground and nowhere
else. When these currents circulate elsewhere,
they may get into the power supply, or the signal
ground, etc, even worse, they may form a loop
and radiate noise. Any of these instances results
in degraded amplifier performance. The output
noise ground that the logical returns for the
output noise currents associated with class D
switching must tie to system ground at the power
exclusively. Signal currents for the inputs,
reference need to be returned to quite ground.
This ground only ties to the signal components
and the GND pin. GND then ties to system
ground.
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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9
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Ordering Information
PAM8012 X X X
Number of pins
Package Type
Pin Configuration
Pin Configuration
A:
B:
A1: OUT+
1. PGND
A2: OUT-
2. OUT-
A3: GND
3. PL
B1: VDD
4. IN-
B2: EN
Number of pins
Z: WCSP9
N: 9
S: eMSOP10
M: 10
5. IN+
B3: PL
6. AGND
C1: VREF
7. VREF
C2: IN+
8. EN
C3: IN-
Package Type
9. VDD
10.OUT+
Part Num ber
PAM8012AZN
PA M8012BSM
Marking
BI
YW
Package Type
MOQ
WCSP9(1.3mm x 1.3mm)
3,000 Units/ Tape & Reel
eMSOP10
2,500 Units/ Tape & Reel
P8012
XXXYW
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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10
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Outline Dimensions
WCSP9
TOP VIEW
BOTTOM VIEW
0. 80
1 .24
1 .32
0. 40
3
1. 24
1. 32
0.80
2
0 .40
1
C
PIN A1 CORNER
B
A
9 X
0. 300
0. 200
SIDE V IEW
0 .42
0 .34
0 .72MAX
0. 30
0. 24
WCSP9
9- Ball Wafer Level Chip Scale Package
Unit: Millimeter
SEATING PLANE
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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11
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Outline Dimensions
eMSOP10
Power Analog Microelectronics, Inc
06/2012 Rev1.3
www.poweranalog.com
12
PAM8012
Mono 2.0W Anti-saturation Class D
Audio Power Amplifier with Power Limit
Datasheet Revision History
Date
Revision
Description
Comment
03/10/2011
Advanced
08/30/2011
Preliminary
09/19/2011
Rev1.0
Initially released.
02/06/2012
Rev1.1
Add eMSOP10 package and update the "RPL vs Po" curve.
05/23/2012
Rev1.2
Update the "Pin Configuration" of eMSOP10 package and thermal info;
Add "Datas heet Revision History" form.
06/06/2012
Rev1.3
Update "Table 2" in "Application Information"
Initially Version.
Add silic on test data.
Power Analog Microelectronics, Inc
06/2012 Rev1.3
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13