Data Sheet

TFA9881
3.4 W PDM input class-D audio amplifier
Rev. 3 — 23 April 2013
Product data sheet
1. General description
The TFA9881 is a mono, filter-free class-D audio amplifier in a 9-bump WLCSP (Wafer
Level Chip-Size Package) with a 400 m pitch.
The digital input interface is an over-sampled Pulse Density Modulated (PDM) bit stream.
The TFA9881 receives audio and control settings via this interface. Dedicated silence
patterns are used to configure the control settings of the device, such as mute, gain, Pulse
Width Modulated (PWM) output slope, clip control and bandwidth extension (this control
mechanism is not required if the default settings are used). The Power-down to Operating
mode transition is triggered when a clock signal is detected.
The device features low RF susceptibility because it has a digital input interface that is
insensitive to clock jitter. The second order closed loop architecture used in the TFA9881
provides excellent audio performance and high supply voltage ripple rejection.
2. Features and benefits

















Small outline WLCSP9 package: 1.3  1.3  0.6 mm
Wide supply voltage range (fully operational from 2.5 V to 5.5 V)
High efficiency (90 %, 4 /20 H load) and low power dissipation
Quiescent power:
 6.5 mW (VDDD = 1.8 V, VDDP = 3.6 V, 4 /20 H load, fclk = 2.048 MHz)
 7.8 mW (VDDD = 1.8 V, VDDP = 3.6 V, 4 /20 H load, fclk = 6.144 MHz)
Output power:
 1.4 W into 4  at 3.6 V supply (THD = 1 %)
 2.7 W into 4  at 5.0 V supply (THD = 1 %)
 3.4 W into 4  at 5.0 V supply (THD = 10 %)
Output noise voltage: 24 V (A-weighted)
Signal-to-noise ratio: 103 dB (VDDP = 5 V, A-weighted)
Fully short-circuit proof across load and to supply lines
Current limiting to avoid audio holes
Thermally protected
Undervoltage and overvoltage protection
High-pass filter for DC blocking
Invalid data protection
Simple two-wire interface for audio and control settings
Left/right selection
Three gain settings:3 dB, 0 dB and +3 dB
PWM output slope setting for EMI reduction
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier










Bandwidth extension to support low sampling frequencies
Clip control for smooth clipping
Mute mode
‘Pop noise' free at all mode transitions
Short power-up time: 2 ms
Short power-down time: 5 s
1.8 V/3.3 V tolerant digital inputs
Low RF susceptibility
Insensitive to input clock jitter
Only two external components required
3. Applications






Mobile phones
PDAs
Portable gaming devices
Portable Navigation Devices (PND)
Notebooks/Netbooks
MP3 players/Portable media players
4. Quick reference data
Table 1.
Quick reference data
All parameters are guaranteed for VTEST = VDDP = 3.6 V; VDDD = 1.8 V; RL = 4 [1]; LL = 20 H[1];
fi = 1 kHz; fclk = 6.144 MHz; Tamb = 25 C; default settings, unless otherwise specified.
Symbol Parameter
Conditions
Min
Typ
Max
Unit
VDDP
power supply voltage
on pin VDDP
2.5
-
5.5
V
VDDD
digital supply voltage
on pin VDDD
1.65
1.8
1.95
V
IDDP
power supply current
Operating mode with load
-
1.5
1.7
mA
IDDD
Po(RMS)
digital supply current
RMS output power
Mute mode
-
1.1
1.2
mA
Power-down mode
-
0.1
1
A
Operating mode
-
1.35
1.5
mA
Mute mode
-
1.25
1.4
mA
Power-down mode
CLK = 0 V; DATA = 0 V
-
2
8
A
VDDP = 3.6 V, fi = 100 Hz
-
1.4
-
W
VDDP = 5.0 V, fi = 100 Hz
-
2.7
-
W
-
3.4
-
W
-
90
-
%
THD + N = 1 %
THD + N = 10 %
VDDP = 5.0 V, fi = 100 Hz
po
[1]
TFA9881
Product data sheet
output power efficiency
Po(RMS) = 1.4 W
RL = load resistance; LL = load inductance.
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
2 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
5. Ordering information
Table 2.
Ordering information
Type number
TFA9881UK
Package
Name
Description
Version
WLCSP9
wafer level chip-size package; 9 bumps; 1.3 x 1.3 x 0.6 mm
TFA9881UK
6. Block diagram
VDDD
TEST
VDDP
B1
C2
B2
SILENCE
PATTERN
DECODER
DATA
A1
LRSEL
A2
CLK
PDM
RECEIVER
TFA9881
HP
FILTER
PWM
C3
OUTA
A3
OUTB
H-BRIDGE
C1
PROTECTION
CIRCUITS:
OTP
OVP
UVP
OCP
POWER DOWN
CONTROL
B3
GND
Fig 1.
TFA9881
Product data sheet
010aaa698
Block diagram
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
3 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
7. Pinning information
7.1 Pinning
TFA9881
1
2
TFA9881
bump A1
index area
3
1
C
A
B
B
A
C
bump A1
index area
010aaa700
3
010aaa699
Bottom view
Fig 2.
2
Transparent top view
Bump configuration for WLCSP9 (bottom view)
Fig 3.
Bump configuration for WLCSP9 (top view)
1
2
3
A
DATA
LRSEL
OUTB
B
VDDD
VDDP
GND
C
CLK
TEST
OUTA
010aaa701
Transparent top view
Fig 4.
Bump mapping for WLCSP9
7.2 Pin description
TFA9881
Product data sheet
Table 3.
Pin description
Symbol
Pin
Type
Description
DATA
A1
I
data input
LRSEL
A2
I
left/right selection
OUTB
A3
O
inverting output
VDDD
B1
P
digital supply voltage (1.8 V)
VDDP
B2
P
power supply voltage (2.5 V to 5.5 V)
GND
B3
P
ground reference
CLK
C1
I
clock input
TEST
C2
I
test pin (must be connected to VDDP)
OUTA
C3
O
non-inverting output
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
4 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
8. Functional description
The TFA9881 is a high-efficiency mono Bridge Tied Load (BTL) class-D audio amplifier
with a digital stereo PDM input interface. A High-Pass (HP) filter removes the DC
components from the incoming PDM stream. This stream is subsequently converted into
two PWM signals. A 3-level PWM scheme supports filterless speaker drive.
8.1 Mode selection and interfacing
The TFA9881 supports four operating modes:
• Power-down mode, with low supply current
• Mute mode, in which the output stages are floating so that the audio input signal is
suppressed
• Operating mode, in which the amplifier is fully operational, delivering an output signal
• Fault mode
The TFA9881 switches to Fault mode automatically when a protection mechanism is
activated (see Section 8.6). The defined patterns required on the CLK and DATA inputs to
select the other three modes are given in Table 4.
Power-down mode is selected when there is no clock signal on the CLK input. Applying
the clock signal will cause the TFA9881 to switch from Power-down mode to Operating
mode. Power-down mode is also activated when the power-down silence pattern (at least
128 consecutive 0xAC bytes) is detected on the DATA input (see Section 8.4.1). The
TFA9881 will switch to Power-down mode after byte 128 and will remain in Power-down
mode as long as a continuous stream of consecutive 0xAC bytes is being received. It will
switch to Operating mode if a byte other than 0xAC is received.
Mute mode is activated when the mute silence pattern (at least 32 consecutive 0x66
bytes) is detected on the DATA input. The TFA9881 will switch to Mute mode after byte 32
and will remain in Mute mode until a byte other than 0x66 is received.
Table 4.
Mode selection
Mode
Pins
CLK frequency
Data pattern
OUTA, OUTB
Power-down
0 Hz
don’t care
floating
2 MHz to 8 MHz
activated after 128 consecutive 0xAC bytes
floating
Mute
2 MHz to 8 MHz
activated after 32 consecutive 0x66 bytes
floating
Operating
2 MHz to 8 MHz
PDM bit stream
switching
8.2 Digital stereo PDM audio input
The TFA9881 supports the digital stereo PDM stream illustrated in Figure 5. Table 5
shows the pin control configuration for left and right selection.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
5 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
CLK
DATA
LEFT
RIGHT
010aaa702
Fig 5.
Digital stereo PDM selection
Table 5.
Left/right selection
LRSEL pin state
Description
LOW
left content amplified
HIGH
right content amplified
8.3 Power up/down sequence
The TFA9881 power-up/power-down sequence is shown in Figure 6. External power
supplies VDDP and VDDD should be within their operating limits before the TFA9881
switches to Operating mode. The TFA9881 should be switched to Power-down mode
before the power supplies are disconnected or turned off.
VDDP,
VDDD
128·fs or 64·fs clock signal
CLK
128 × 0xAC
DATA
PDM
OUTA,
OUTB
Power-down
32 times
0x66
PDM
floating
switching
td(on)
0x66 .......
Operating
Mute
32 times 96 times
0xAC
0xAC
0xAC .......
PDM
floating
switching
Operating
Mute
switching
Power-down
td(on)
Operating
Power-down
td(off)
010aaa710
Fig 6.
Power-up/power-down sequence
Table 6.
Power-up/power-down timing
All parameters are guaranteed for VTEST = VDDP = 3.6 V; VDDD = 1.8 V; RL = 4 [1]; LL = 20 H[1];
fi = 1 kHz; fclk = 6.144 MHz; Tamb = 25 C; default settings, unless otherwise specified.
Symbol
td(on)
td(off)
TFA9881
Product data sheet
Parameter
Conditions
Min
Typ
Max
Unit
turn-on delay time
[2]
-
-
2
ms
turn-off delay time
[2]
-
-
5
s
[1]
RL = load resistance; LL = load inductance.
[2]
Inversely proportional to fclk.
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
6 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
8.4 Control settings
Control settings are not needed if the default values are adequate.
8.4.1 Silence pattern recognition
The TFA9881 can detect control settings on the PDM input by means of silence pattern
recognition. A silence pattern has the following properties:
• All audio bytes have the same value
• Each audio byte must contain four zeros and four ones
The ten silence patterns recognized by the TFA9881 are listed in the first column of
Table 7. The second column contains the related audio bytes that are generated when the
silence patterns are phase shifted by 1, 2, 3, 4, 5, 6 and 7 bits.
The TFA9881 reacts as follows on receiving a silence pattern (see Table 8):
• After receiving 32 consecutive silence pattern audio bytes, the TFA9881 sets the
outputs floating.
• After receiving 128 consecutive silence pattern audio bytes, the TFA9881 activates
the appropriate control setting (see column three of Table 7).
Remark: Only the control settings associated with silence patterns containing audio bytes
0xD2, 0xD4, 0xD8, 0xE1, 0xE2, 0xE4 and 0xAA can be set during power-up (before the
power-up delay time, td(on), has expired). After power-up, only silence patterns containing
bytes 0x66 and 0xAC will be recognized. All other silence patterns are ignored.
All control settings can be activated when:
• control silence patterns are transmitted after the TFA9881 has been switched to
Power-down mode on receipt of a power-down silence pattern (at least 128
consecutive 0xAC bytes)
• control silence patterns are transmitted after the clock input has stopped and then
started again (power-up)
If a silence pattern containing more than 128 consecutive silence pattern audio bytes is
received during power-up, the TFA9881 outputs will remain floating until a different audio
byte is received. It will then switch to Operating mode. Once the TFA9881 has powered
up, only ‘mute’ (0x66) and ‘power-down’ (0xAC) control patterns are recognized.
All registers are reset to their default values if silence pattern 0xAA is received or the VDDD
supply is removed.
Table 7.
TFA9881
Product data sheet
Silence patterns
Byte
Related bytes[1]
Control settings
0xD1
0xE8/74/3A/1D/8E/47/A3
reserved for test purposes
0xD2
0x69/B4/5A/2D/96/4B/A5
clip control on; see Section 8.4.2
0xD4
0x6A/35/9A/4D/A6/53/A9
gain = 3 dB (VDDP = 2.5 V); see Section 8.4.3
0xD8
0x6C/36/1B/8D/C6/63/B1
gain = +3 dB (VDDP = 5.0 V); see Section 8.4.3
0xE1
0xF0/78/3C/1E/0F/87/C3
slope low (EMC); see Section 8.4.4
0xE2
0x71/B8/5C/2E/17/8B/C5
Dynamic Power Stage Activation (DPSA) off;
see Section 8.4.5
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
7 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
Table 7.
Silence patterns …continued
Byte
Related bytes[1]
Control settings
0xE4
0x72/39/9C/4E/27/93/C9
bandwidth extension on (fs = 32 kHz or
fclk = 64fs); see Section 8.4.6
0xAA
0x55
defaults; no mute, reset settings to default
0x66[2]
0x33/99/CC
Mute mode (no setting); see Section 8.4.7
0xAC[2]
0x56/2B/95/CA/65/B2/59
Power-down mode; see Section 8.4.8
[1]
The related bytes are the bytes from the first column phase shifted by 1, 2, 3, 4, 5, 6 and 7 bits.
[2]
A silence pattern containing this byte will be recognized once the TFA9881 has powered up.
Table 8.
Silence pattern recognition
Bytes 1 to 32 .................... 33 ................................. 127, 128 129
Mute mode (outputs floating)
control setting activated
8.4.2 Clip control
TFA9881 clip control is off by default. Clip control can be turned on via silence pattern
0xD2 (see Section 8.4.1). The TFA9881 clips smoothly with clip control on. Output power
is at maximum with clip control off.
8.4.3 Gain selection
Signal conversion from digital audio in to PWM modulated audio out is independent of
supply voltages VDDP and VDDD. At the default gain setting (0 dB), the audio output signal
level is just below the clipping point at a supply voltage of 3.6 V at 6 dBFS (peak) input.
The TFA9881 supports two further gain settings to support full output power at
VDDP = 2.5 V and VDDP = 5.0 V. The gain settings can be selected via silence patterns
0xD4 and 0xD8 (see Section 8.4.1).
Table 9 details the corresponding peak output voltage level at 6 dBFS for the three gain
settings.
Table 9.
Output voltage
All parameters are guaranteed for VTEST = VDDP = 3.6 V; VDDD = 1.8 V; LL = 20 H[1], fclk = 6.144 MHz, Tamb = 25 C unless
otherwise specified.
Symbol
Parameter
Conditions
VoM
peak output voltage
at 6 dBFS (peak) digital input
[1]
Min
Typ
Max
Unit
gain = 3 dB, VDDP = 2.5 V, RL = 4 
[1]
-
2.3
-
V
gain = 0 dB, VDDP = 3.6 V, RL = 4 ; default
[1]
-
3.3
-
V
gain = +3 dB, VDDP = 5.0 V, RL = 8 , LL = 44 H
[1]
-
4.7
-
V
RL = load resistance; LL = load inductance.
8.4.4 PWM slope selection
The rise and fall times of the PWM output edges can be set to one of two values, as
detailed in Table 10. The default setting is ‘slope normal’ (10 ns with VDDP = 3.6 V). ‘Slope
low’ is selected via silence pattern 0xE1 (see Section 8.4.1). This function is implemented
to reduce Electro-Magnetic Interference (EMI).
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
8 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
Table 10.
Slope rise and fall times
Setting
Rise and fall times of the PWM output edges
slope low
40 ns with VDDP = 3.6 V
slope normal; default setting
10 ns with VDDP = 3.6 V
8.4.5 Dynamic Power Stage Activation (DPSA)
The TFA9881 uses DPSA to regulate current consumption in line with the level of the
incoming audio stream. This function switches off power stage sections that are not
needed, reducing current consumption.
Each of the TFA9881 H-bridge power stages is divided into eight sections. The number of
power stage sections activated depends on the level of the incoming audio stream. The
thresholds used by the DPSA to determine how many stages are switched on are given in
Table 11. The DPSA signal is used as a reference signal for switching power stage
sections on and off. The DPSA signal will rise in tandem with the rectified audio input
signal. When the rectified audio input signal falls, the DPSA decreases with a negative
exponential function, as illustrated in Figure 7.
The DPSA function can be switched off via silence pattern 0xE2. When DPSA is off, all
power stage sections are activated in Operating mode.
Table 11.
DPSA input levels
Setting
Number of power stage sections active
 0.035  full scale (29 dBFS)
1
> 0.035  full scale (29 dBFS)
2
> 0.07  full scale (23 dBFS)
4
> 0.105  full scale (19.5 dBFS)
8
DPSA signal
0.105 × full scale
0.07 × full scale
0.035 × full scale
1 section
8 sections
4 sections
2 sections
010aaa713
Fig 7.
Dynamic Power Stage Activation
8.4.6 Bandwidth extension
The TFA9881 output spectrum has a sigma-delta converter characteristic. Figure 8
illustrates the output power spectrum of the TFA9881 when it is receiving a PDM input
stream without audio content and with bandwidth extension off. The quantization noise is
shaped above the band of interest. The band of interest (bandwidth) is determined by the
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
9 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
corner frequency where the noise is increasing. The bandwidth in Figure 8 scales with the
clock input frequency. This bandwidth can be extended via the bandwidth extension
silence pattern (0xE4; see Section 8.4.1). The PWM switching frequency also scales with
the bandwidth extension setting. The bandwidth and the PWM switching frequency when
bandwidth extension is on and off are given in Table 12.
Remark: The Bandwidth extension should be switched off when fclk > 4.1 MHz.
Table 12.
Bandwidth extension setting
Setting
Bandwidth
Switching frequency
bandwidth extension on
f clk
-------128
f clk
-------8
bandwidth extension off; default setting
f clk
-------256
f clk
-------16
010aaa709
−40
output
(dBFS)
−80
−120
−160
10
102
103
104
105
106
f (Hz)
Fig 8.
Output power spectrum, fclk = 6.144 MHz
8.4.7 Mute
Mute mode is activated when the mute silence pattern (at least 32 consecutive 0x66
bytes) is applied on the DATA input. The TFA9881 remains in Mute mode as long as the
0x66 pattern is repeated. It will return to Operating mode when a pattern other than 0x66
is received. Transitions to and from Mute mode occur as soon as the relevant pattern is
recognized by the TFA9881 (hard mute and hard unmute).
8.4.8 Power-down
Power-down mode is activated when the power-down silence pattern (at least 128
consecutive 0xAC bytes) is applied on the DATA input. The TFA9881 remains in
Power-down mode as long as the 0xAC pattern is repeated. It will return to Operating
mode when a pattern other than 0xAC is received.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
10 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
8.5 High-pass filter
The high-pass filter will block the DC components in the incoming audio stream. The
cut-off frequency, fhigh(3dB), is determined by the clock frequency, and is defined in
Equation 1:
– f clk  ln  8191  8192 
f high  –3dB  = ----------------------------------------------------16  k  
(1)
where k depends on the bandwidth extension setting (see Section 8.4.6):
• k = 2 if bandwidth extension is off
• k = 1 if bandwidth extension is on
fhigh(3dB) is about 7.5 Hz at a clock frequency of 6.144 MHz when bandwidth extension is
off. The high-pass filter is always enabled.
Remark: Care should be taken when DC dither is applied to the PDM audio input stream.
The PDM source should slowly increase this DC-dither to avoid pop noise.
8.6 Protection mechanisms
The following protection circuits are included in the TFA9881:
•
•
•
•
•
Invalid Data Protection (IDP)
OverTemperature Protection (OTP)
OverVoltage Protection (OVP)
UnderVoltage Protection (UVP)
OverCurrent Protection (OCP)
The reaction of the device to fault conditions differs depending on the protection circuit
involved.
8.6.1 Invalid Data Protection (IDP)
IDP is designed to detect the absence of a data input signal. IDP is activated when 128
consecutive 0s or 1s are received on the DATA input.
IDP is disabled when a PDM stream that does not contain 128 consecutive 0s or 1s is
received. The output stages are set floating when IDP is active.
Remark: The maximum PDM input modulation depth should be limited to avoid false IDP
triggering.
8.6.2 OverTemperature Protection (OTP)
OTP prevents heat damage to the TFA9881. It is triggered when the junction temperature
exceeds 130 °C. When this happens, the output stages are set floating. OTP is cleared
automatically via an internal timer (100 ms with fclk = 6.144 MHz), after which the output
stages will start to operate normally again.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
11 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
8.6.3 Supply voltage protection mechanisms (UVP and OVP)
UVP is activated, setting the outputs floating, if VDDP drops below the undervoltage
protection threshold, VP(uvp). This transition will be silent, without pop noise. When the
supply voltage rises above VP(uvp) again, the system will be restarted after 100 ms with
fclk = 6.144 MHz.
OVP is activated, setting the power stages floating, if the supply voltage rises above the
overvoltage protection threshold, VP(ovp). The power stages are re-enabled as soon as the
supply voltage drops below VP(ovp) again. The system will be restarted after 100 ms with
fclk = 6.144 MHz.
Note that a supply voltage > 5.5 V may damage the TFA9881.
8.6.4 OverCurrent Protection (OCP)
OCP will detect a short circuit across the load or between one of the amplifier outputs and
one of the supply lines. If the output current exceeds the overcurrent protection threshold
(IO(ocp)), it will be limited to IO(ocp) while the amplifier outputs are switching (the amplifier is
not powered down completely). This is called current limiting. The amplifier can
distinguish between an impedance drop at the loudspeaker and a low-ohmic short circuit
across the load or to one of the supply lines. The impedance threshold depends on which
supply voltage is being used:
• In the event of a short circuit across the load or a short to one of the supply lines, the
audio amplifier is switched off completely. It will try to restart again after approximately
100 ms with fclk = 6.144 MHz. If the short-circuit condition is still present after this
time, this cycle will be repeated. Average dissipation will be low because of the short
duty cycle.
• In the event of an impedance drop (e.g. due to dynamic behavior of the loudspeaker),
the same protection mechanism will be activated. The maximum output current is
again limited to IO(ocp), but the amplifier will not switch off completely (thus preventing
audio holes from occurring). This will result in a clipped output signal without artifacts.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
12 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
9. Internal circuitry
Table 13.
Internal circuitry
Pin
Symbol
A1
DATA
C1
CLK
Equivalent circuit
A1, C1
ESD
B3
010aaa714
B1
VDDD
B2
VDDP
B1, B2
ESD
B3
010aaa715
A2
LRSEL
C2
TEST
B2
A2, C2
ESD
B3
010aaa716
A3
OUTB
C3
OUTA
B2
A3, C3
B3
010aaa717
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
13 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
10. Limiting values
Table 14. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol Parameter
Conditions
Min
Max
Unit
0.3
+5.5
V
VDDP
power supply voltage
on pin VDDP
VDDD
digital supply voltage
on pin VDDD
0.3
+1.95
V
Tj
junction temperature
-
+150
C
Tstg
storage temperature
55
+150
C
Tamb
ambient temperature
40
+85
C
Vx
voltage on pin x
pins CLK and DATA
0.3
+3.6
V
pins OUTA and OUTB
0.6
VDDP + 0.6
V
0.6
VDDP
V
pins OUTA and OUTB
8
+8
kV
any other pin
2
+2
kV
according to the Charge Device Model (CDM)
[1]
500
+500
V
according to the Machine Model (MM)
[1]
200
+200
V
pins TEST and LRSEL
VESD
[1]
electrostatic discharge voltage
according to the Human Body Model (HBM)
[1]
Measurements taken on the TFA9881 in a HVSON10 package (engineering samples) due to handling restrictions with WLCSP9.
11. Thermal characteristics
Table 15.
Thermal characteristics
Symbol
Parameter
Conditions
Rth(j-a)
thermal resistance from junction to ambient
in free air; natural convection
JEDEC test board
[1]
2-layer application board
j-top
thermal characterization parameter from
junction to top of package
[1]
Measured on a JEDEC high K-factor test board (standard EIA/JESD 51-7).
[2]
Value depends on where measurement is taken on package.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
[2]
Typ
Unit
128
K/W
97
K/W
12
K/W
© NXP B.V. 2013. All rights reserved.
14 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
12. Characteristics
12.1 DC characteristics
Table 16. DC characteristics
All parameters are guaranteed for VTEST = VDDP = 3.6 V; VDDD = 1.8 V; RL = 4 [1]; LL = 20 H[1]; fi = 1 kHz; fclk = 6.144 MHz;
Tamb = 25 C; default settings, unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
VDDP
power supply voltage
on pin VDDP
2.5
-
5.5
V
VDDD
digital supply voltage
on pin VDDD
1.65
1.8
1.95
V
IDDP
power supply current
Operating mode with load
-
-
1.5
1.7
mA
fclk = 2.048 MHz
bandwidth extension on
-
1.38
-
mA
1.1
1.2
mA
-
0.1
1
A
-
-
1.35
1.5
mA
fclk = 2.048 MHz
bandwidth extension on
-
0.83
-
mA
-
-
1.25
1.4
mA
fclk = 2.048 MHz
bandwidth extension on
-
0.78
-
mA
Power-down mode
CLK = 0 V, DATA = 0 V
-
2
8
A
DPSA off
-
125
150
m
absolute value
-
-
3
mV
Mute mode
Power-down mode
IDDD
digital supply current
Operating mode
Mute mode
Series resistance output power switches
RDSon
drain-source on-state resistance
Amplifier output pins; pins OUTA and OUTB
VO(offset)
output offset voltage
DATA, CLK and LRSEL
VIH
HIGH-level input voltage
0.7VDDD -
3.6
V
VIL
LOW-level input voltage
-
-
0.3VDDD
V
Ci
input capacitance
-
-
3
pF
Protection
Tact(th_prot)
thermal protection activation temperature
130
-
150
C
VP(ovp)
overvoltage protection supply voltage
5.5
-
6.0
V
VP(uvp)
undervoltage protection supply voltage
2.3
-
2.5
V
IO(ocp)
overcurrent protection output current
1.45
-
-
A
[1]
RL = load resistance; LL = load inductance.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
15 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
12.2 AC characteristics
Table 17. AC characteristics
All parameters are guaranteed for VTEST = VDDP = 3.6 V; VDDD = 1.8 V; RL = 4 [1]; LL = 20 H[1]; fi = 1 kHz; fclk = 6.144 MHz;
Tamb = 25 C; default settings, unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
VDDP = 3.6 V, fi = 100 Hz
-
1.4
-
W
VDDP = 5.0 V, fi = 100 Hz
-
2.7
-
W
VDDP = 3.6 V, fi = 100 Hz
-
0.75
-
W
VDDP = 5.0 V, fi = 100 Hz
-
1.45
-
W
Output power
Po(RMS)
RMS output power
THD + N = 1 %
THD + N = 1 %; RL = 8 ; LL = 44 H
THD + N = 10 %
VDDP = 3.6 V, fi = 100 Hz
-
1.75
-
W
VDDP = 5.0 V, fi = 100 Hz
-
3.4
-
W
VDDP = 3.6 V, fi = 100 Hz
-
0.95
-
W
VDDP = 5.0 V, fi = 100 Hz
-
1.85
-
W
-
90
-
%
-
0.02
0.1
%
THD + N = 10 %; RL = 8 ; LL = 44 H
Performance
po
output power efficiency
THD+N
total harmonic distortion-plus-noise Po(RMS) = 100 mW
Po(RMS) = 1.4 W
Vn(o)
output noise voltage
A-weighted
-
24
-
V
S/N
signal-to-noise ratio
VDDP = 5 V; Vo = 3.4 V (RMS); A-weighted
-
103
-
dB
PSRR
power supply rejection ratio
Vripple = 200 mV; fripple = 217 Hz
-
85
-
dB
VoM
peak output voltage
At 6 dBFS (peak) digital input
gain = 3 dB; VDDP = 3.6 V
RL = 4 ; LL = 20 H
-
2.3
-
V
gain = 0 dB; VDDP = 3.6 V
RL = 4 ; LL = 20 H
3.1
3.3
3.5
V
gain = +3 dB; VDDP = 5.0 V
RL = 8 ; LL = 44 H
-
4.7
-
V
Power-up, power-down and propagation times
turn-on delay time
[2]
-
-
2
ms
td(off)
turn-off delay time
[2]
-
-
5
s
tPD
propagation delay
[2]
-
-
55
s
td(on)
[1]
RL = load resistance; LL = load inductance.
[2]
Inversely proportional to fclk.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
16 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
12.3 PDM timing characteristics
Table 18. PDM timing characteristics
All parameters are guaranteed for VTEST = VDDP = 3.6 V; VDDD = 1.8 V; RL = 4 [1]; LL = 20 H[1]; fi = 1 kHz; fclk = 6.144 MHz;
Tamb = 25 C; default settings, unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
fclk
clock frequency
2
-
8
MHz
clk
clock duty cycle
40
-
60
%
th
hold time
after clock HIGH
7
-
-
ns
after clock LOW
7
-
-
ns
after clock HIGH
10
-
-
ns
after clock LOW
10
-
-
ns
set-up time
tsu
[1]
RL = load resistance; LL = load inductance.
CLK
tsu(CLKH)
tsu(CLKL)
th(CLKH)
th(CLKL)
DATA
010aaa711
Fig 9.
TFA9881
Product data sheet
PDM timing
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
17 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
13. Application information
13.1 ElectroMagnetic Compatibility (EMC)
EMC standards define to what degree a (sub)system is susceptible to externally imposed
electromagnetic influences and to what degree a (sub)system is responsible for emitting
electromagnetic signals, when in Standby mode or Operating mode.
EMC immunity and emission values are normally measured over a frequency range from
180 kHz up to 3 GHz.
13.1.1 Immunity
A major reason why amplifier devices pick up high frequency signals, and (after detection)
manifest these in the device's audio band, is the presence of analog circuits inside the
device or in the (sub)system.
The TFA9881 has digital inputs and digital outputs. Comparative tests on a
TFA9881-based (sub)system show that the impact of externally imposed electromagnetic
signals on the device is negligible in both Standby and Operating modes.
13.1.2 Emissions
Since the TFA9881 is a class-D amplifier with digitally switched outputs in a BTL
configuration, it can potentially generate emissions due to the steep edges on the
amplifier outputs. External components can be used to suppress these emissions.
However, the TFA9881 features built-in slope control to suppress such emissions by
reducing the slew rate of the BTL output signals. By reducing the slew rate, the emissions
are reduced by 10 dB when compared with full-speed operation.
13.2 Supply decoupling and filtering
A ceramic decoupling capacitor of between 4.7 F and 10 F should be placed close to
the TFA9881 for decoupling the VDDP supply. This minimizes the size of the
high-frequency current loop, thereby optimizing EMC performance. The TEST bump can
be used to route the VDDP bump connection (without using a PCB via).
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
18 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
13.3 Typical application diagram (simplified)
DATA
CLK
1.8 V
VDDD
A2
VDDP
TEST
LRSEL
battery
C2
B2
A1
C1
C3
OUTA
left speaker
4 Ω or 8 Ω
TFA9881UK
B1
A3
OUTB
B3
BASEBAND
PROCESSOR
CVDDP
4.7 μF
GND
CVDDD
100 nF
battery
DATA
CLK
1.8 V
VDDD
A2
VDDP
TEST
LRSEL
PDM output
C2
B2
A1
C1
C3
OUTA
right speaker
4 Ω or 8 Ω
TFA9881UK
B1
A3
OUTB
B3
GND
CVDDD
100 nF
CVDDP
4.7 μF
010aaa712
Fig 10. Typical stereo application (simplified)
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
19 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
13.4 Curves measured in reference design (demonstration board)
All measurements were taken with VDDD = 1.8 V, fclk = 6.144 MHz, clip control off, DPSA
off and slope normal, unless otherwise specified.
001aam634
102
THD+N
(%)
THD+N
(%)
10
10
1
1
10−1
001aam636
102
10−1
(1)
(1)
(3)
10−2
10−2
(2)
(2)
(3)
10−3
10−3
10−2
10−1
1
10
10−3
10−3
10−2
10−1
1
Po (W)
10
Po (W)
(1) fi = 6 kHz.
(1) fi = 6 kHz.
(2) fi = 1 kHz.
(2) fi = 1 kHz.
(3) fi = 100 Hz.
(3) fi = 100 Hz.
a. VDDP = 3.6 V, RL = 8 , LL = 44 H
b. VDDP = 5 V, RL = 8 , LL = 44 H
001aam633
102
001aam635
102
THD+N
(%)
THD+N
(%)
10
10
1
1
(1)
10−1
10−1
(1)
(3)
10−3
10−3
(3)
(2)
10−2
10−2
10−2
10−1
1
10
10−3
10−3
(2)
10−2
Po (W)
1
10
Po (W)
(1) fi = 6 kHz.
(1) fi = 6 kHz.
(2) fi = 1 kHz.
(2) fi = 1 kHz.
(3) fi = 100 Hz.
(3) fi = 100 Hz.
c. VDDP = 3.6 V, RL = 4 , LL = 20 H
10−1
d. VDDP = 5 V, RL = 4 , LL = 20 H
Fig 11. THD+N as a function of output power
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
20 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
001aam638
10
001aam640
10
THD+N
(%)
THD+N
(%)
1
1
10−1
10−1
(1)
10−2
(1)
10−2
(2)
10−3
10
102
103
104
105
(2)
10−3
10
102
103
104
105
fi (Hz)
fi (Hz)
(1) Po = 500 mW.
(1) Po = 500 mW.
(2) Po = 100 mW.
(2) Po = 100 mW.
a. VDDP = 3.6 V, RL = 8 , LL = 44 H
b. VDDP = 5 V, RL = 8 , LL = 44 H
001aam637
10
001aam639
10
THD+N
(%)
THD+N
(%)
1
1
10−1
10−1
(1)
(1)
(2)
10−2
10−3
10
102
(2)
10−2
103
104
105
10−3
10
102
103
104
fi (Hz)
(1) Po = 1 W.
(1) Po = 1 W.
(2) Po = 100 mW.
(2) Po = 100 mW.
c. VDDP = 3.6 V, RL = 4 , LL = 20 H
105
fi (Hz)
d. VDDP = 5 V, RL = 4 , LL = 20 H
Fig 12. THD+N as a function of frequency
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
21 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
001aam641
10
001aam642
10
THD+N+IMD
(%)
THD+N+IMD
(%)
1
1
10−1
10−1
(4)
(4)
(3)
(2)
(1)
10−2
10−3
10
102
103
104
(3)
(2)
(1)
10−2
105
10−3
10
102
103
fi (Hz)
104
105
fi (Hz)
(1) Vripple = 0 V (fripple = 0 Hz).
(1) Vripple = 0 V (fripple = 0 Hz).
(2) fripple = 217 Hz.
(2) fripple = 217 Hz.
(3) fripple = 1 kHz.
(3) fripple = 1 kHz.
(4) fripple = 6 kHz.
(4) fripple = 6 kHz.
a. VDDP = 3.6 V, RL = 4 , LL = 20 H, Po = 100 mW
Vripple = 200 mV (RMS)
b. VDDP = 5 V, RL = 4 , LL = 20 H, Po = 100 mW
Vripple = 200 mV (RMS)
Fig 13. THD+N + power supply intermodulation distortion as a function of frequency
001aam643
1.0
001aam644
−10
PSRR
(dB)
G
(dB)
−30
0.5
−50
0
−70
(1)
−0.5
−1.0
−90
10
102
103
104
105
−110
(2)
10
102
fi (Hz)
VDDP = 3.6 V, RL = 4 , LL = 20 H, Po = 500 mW.
103
104
105
fripple (Hz)
(1) VDDP = 3.6 V.
(2) VDDP = 5 V.
RL = 4 , LL = 20 H, Vripple = 200 mV (RMS).
Fig 14. Normalized gain as a function of frequency
TFA9881
Product data sheet
Fig 15. PSRR as a function of ripple frequency
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
22 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
001aam632
110
S/N ratio
(dB)
90
(1)
70
(2)
50
30
10
10−3
10−2
10−1
1
10
Po (W)
(1) A-weighted.
(2) 20 kHz brickwall filter.
VDDP = 5 V, RL = 4 , LL = 20 H, reference signal: 3.4 V (RMS).
Fig 16. S/N ratio as a function of output power
001aam649
5
Po
(W)
Po
(W)
(1)
4
001aam650
4
(1)
3
(2)
(2)
3
2
(3)
2
(3)
(4)
(4)
1
1
0
0
2
3
4
5
6
2
3
4
VDDP (V)
5
6
VDDP (V)
(1) THD+N = 10 %, RL = 4 , LL = 20 H.
(1) THD+N = 10 %, RL = 4 , LL = 20 H.
(2) THD+N = 1 %, RL = 4 , LL = 20 H.
(2) THD+N = 1 %, RL = 4 , LL = 20 H.
(3) THD+N = 10 %, RL = 8 , LL = 44 H.
(3) THD+N = 10 %, RL = 8 , LL = 44 H.
(4) THD+N = 1 %, RL = 8 , LL = 44 H.
(4) THD+N = 1 %, RL = 8 , LL = 44 H.
a. fi = 100 Hz, clip control off
b. fi = 100 Hz, clip control on
Fig 17. Output power as a function of supply voltage
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
23 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
001aam647
0.15
001aam645
0.4
P
(W)
P
(W)
(2)
(2)
0.3
0.10
0.2
(1)
(1)
0.05
0.1
0
10−3
10−2
10−1
1
0
10−3
10
10−2
10−1
1
10
Po (W)
Po (W)
(1) VDDP = 3.6 V.
(1) VDDP = 3.6 V.
(2) VDDP = 5 V.
(2) VDDP = 5 V.
a. RL = 8, LL = 44 H, fi = 1 kHz, DPSA on
b. RL = 4, LL = 20 H, fi = 1 kHz, DPSA on
Fig 18. Power dissipation as a function of output power
001aam648
100
(1)
η
(%)
001aam646
100
(2)
80
80
60
60
40
40
20
20
0
(2)
(1)
η
(%)
0
0
0.5
1.0
1.5
2.0
0
0.5
1.0
Po (W)
1.5
2.0
2.5
3.0
3.5
Po (W)
(1) VDDP = 3.6 V.
(1) VDDP = 3.6 V.
(2) VDDP = 5 V.
(2) VDDP = 5 V.
a. RL = 8, LL = 44 H, fi = 1 kHz, DPSA on
b. RL = 4, LL = 20 H, fi = 1 kHz, DPSA on
Fig 19. Efficiency as a function of output power
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
24 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
14. Package outline
WLCSP9: wafer level chip-size package;
9 bumps; 1.27 x 1.31 x 0.6 mm (Backside Coating included)
A
E
TFA9881
B
ball A1
index area
A2
A
D
A1
detail X
e1
C
C A B
C
Øv
Øw
b
e
y
y1 C
C
e
e2
B
A
ball A1
index area
1
2
3
X
0
2 mm
scale
Dimensions (mm are the original dimensions)
Unit
mm
max
nom
min
A
0.6
A1
A2
b
D
E
0.22 0.38 0.28 1.30 1.34
0.20 0.36 0.26 1.27 1.31
0.18 0.34 0.24 1.24 1.28
e
e1
e2
0.4
0.8
0.8 0.015 0.04 0.02
v
w
y
wlcsp9_tfa9881_po
Outline
version
References
IEC
JEDEC
JEITA
European
projection
Issue date
13-04-05
13-04-09
TFA9881
Fig 20. Package outline TFA9881 (WLCSP9)
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
25 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
15. Soldering of WLCSP packages
15.1 Introduction to soldering WLCSP packages
This text provides a very brief insight into a complex technology. A more in-depth account
of soldering WLCSP (Wafer Level Chip-Size Packages) can be found in application note
AN10439 “Wafer Level Chip Scale Package” and in application note AN10365 “Surface
mount reflow soldering description”.
Wave soldering is not suitable for this package.
All NXP WLCSP packages are lead-free.
15.2 Board mounting
Board mounting of a WLCSP requires several steps:
1. Solder paste printing on the PCB
2. Component placement with a pick and place machine
3. The reflow soldering itself
15.3 Reflow soldering
Key characteristics in reflow soldering are:
• Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to
higher minimum peak temperatures (see Figure 21) than a PbSn process, thus
reducing the process window
• Solder paste printing issues, such as smearing, release, and adjusting the process
window for a mix of large and small components on one board
• Reflow temperature profile; this profile includes preheat, reflow (in which the board is
heated to the peak temperature), and cooling down. It is imperative that the peak
temperature is high enough for the solder to make reliable solder joints (a solder paste
characteristic) while being low enough that the packages and/or boards are not
damaged. The peak temperature of the package depends on package thickness and
volume and is classified in accordance with Table 19.
Table 19.
Lead-free process (from J-STD-020D)
Package thickness (mm)
Package reflow temperature (C)
Volume (mm3)
< 350
350 to 2000
> 2000
< 1.6
260
260
260
1.6 to 2.5
260
250
245
> 2.5
250
245
245
Moisture sensitivity precautions, as indicated on the packing, must be respected at all
times.
Studies have shown that small packages reach higher temperatures during reflow
soldering, see Figure 21.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
26 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
maximum peak temperature
= MSL limit, damage level
temperature
minimum peak temperature
= minimum soldering temperature
peak
temperature
time
001aac844
MSL: Moisture Sensitivity Level
Fig 21. Temperature profiles for large and small components
For further information on temperature profiles, refer to application note AN10365
“Surface mount reflow soldering description”.
15.3.1 Stand off
The stand off between the substrate and the chip is determined by:
• The amount of printed solder on the substrate
• The size of the solder land on the substrate
• The bump height on the chip
The higher the stand off, the better the stresses are released due to TEC (Thermal
Expansion Coefficient) differences between substrate and chip.
15.3.2 Quality of solder joint
A flip-chip joint is considered to be a good joint when the entire solder land has been
wetted by the solder from the bump. The surface of the joint should be smooth and the
shape symmetrical. The soldered joints on a chip should be uniform. Voids in the bumps
after reflow can occur during the reflow process in bumps with high ratio of bump diameter
to bump height, i.e. low bumps with large diameter. No failures have been found to be
related to these voids. Solder joint inspection after reflow can be done with X-ray to
monitor defects such as bridging, open circuits and voids.
15.3.3 Rework
In general, rework is not recommended. By rework we mean the process of removing the
chip from the substrate and replacing it with a new chip. If a chip is removed from the
substrate, most solder balls of the chip will be damaged. In that case it is recommended
not to re-use the chip again.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
27 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
Device removal can be done when the substrate is heated until it is certain that all solder
joints are molten. The chip can then be carefully removed from the substrate without
damaging the tracks and solder lands on the substrate. Removing the device must be
done using plastic tweezers, because metal tweezers can damage the silicon. The
surface of the substrate should be carefully cleaned and all solder and flux residues
and/or underfill removed. When a new chip is placed on the substrate, use the flux
process instead of solder on the solder lands. Apply flux on the bumps at the chip side as
well as on the solder pads on the substrate. Place and align the new chip while viewing
with a microscope. To reflow the solder, use the solder profile shown in application note
AN10365 “Surface mount reflow soldering description”.
15.3.4 Cleaning
Cleaning can be done after reflow soldering.
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
28 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
16. Revision history
Table 20.
Revision history
Document ID
Release date
Data sheet status
TFA9881 v.3
20130423
Product data sheet
Modifications:
TFA9881 v.2
Modifications:
TFA9881 v.1
TFA9881
Product data sheet
•
Supersedes
TFA9881 v.2
Update package outline
20110401
•
•
Change notice
Product data sheet
TFA9881 v.1
Data sheet status changed to ‘Product data sheet’
Table 16: parameter values changed - VP(ovp)
20110105
Preliminary data sheet
-
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
-
© NXP B.V. 2013. All rights reserved.
29 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
17. Legal information
17.1 Data sheet status
Document status[1][2]
Product status[3]
Definition
Objective [short] data sheet
Development
This document contains data from the objective specification for product development.
Preliminary [short] data sheet
Qualification
This document contains data from the preliminary specification.
Product [short] data sheet
Production
This document contains the product specification.
[1]
Please consult the most recently issued document before initiating or completing a design.
[2]
The term ‘short data sheet’ is explained in section “Definitions”.
[3]
The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status
information is available on the Internet at URL http://www.nxp.com.
17.2 Definitions
Draft — The document is a draft version only. The content is still under
internal review and subject to formal approval, which may result in
modifications or additions. NXP Semiconductors does not give any
representations or warranties as to the accuracy or completeness of
information included herein and shall have no liability for the consequences of
use of such information.
Short data sheet — A short data sheet is an extract from a full data sheet
with the same product type number(s) and title. A short data sheet is intended
for quick reference only and should not be relied upon to contain detailed and
full information. For detailed and full information see the relevant full data
sheet, which is available on request via the local NXP Semiconductors sales
office. In case of any inconsistency or conflict with the short data sheet, the
full data sheet shall prevail.
Product specification — The information and data provided in a Product
data sheet shall define the specification of the product as agreed between
NXP Semiconductors and its customer, unless NXP Semiconductors and
customer have explicitly agreed otherwise in writing. In no event however,
shall an agreement be valid in which the NXP Semiconductors product is
deemed to offer functions and qualities beyond those described in the
Product data sheet.
17.3 Disclaimers
Limited warranty and liability — Information in this document is believed to
be accurate and reliable. However, NXP Semiconductors does not give any
representations or warranties, expressed or implied, as to the accuracy or
completeness of such information and shall have no liability for the
consequences of use of such information. NXP Semiconductors takes no
responsibility for the content in this document if provided by an information
source outside of NXP Semiconductors.
In no event shall NXP Semiconductors be liable for any indirect, incidental,
punitive, special or consequential damages (including - without limitation - lost
profits, lost savings, business interruption, costs related to the removal or
replacement of any products or rework charges) whether or not such
damages are based on tort (including negligence), warranty, breach of
contract or any other legal theory.
Notwithstanding any damages that customer might incur for any reason
whatsoever, NXP Semiconductors’ aggregate and cumulative liability towards
customer for the products described herein shall be limited in accordance
with the Terms and conditions of commercial sale of NXP Semiconductors.
Right to make changes — NXP Semiconductors reserves the right to make
changes to information published in this document, including without
limitation specifications and product descriptions, at any time and without
notice. This document supersedes and replaces all information supplied prior
to the publication hereof.
TFA9881
Product data sheet
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in life support, life-critical or
safety-critical systems or equipment, nor in applications where failure or
malfunction of an NXP Semiconductors product can reasonably be expected
to result in personal injury, death or severe property or environmental
damage. NXP Semiconductors and its suppliers accept no liability for
inclusion and/or use of NXP Semiconductors products in such equipment or
applications and therefore such inclusion and/or use is at the customer’s own
risk.
Applications — Applications that are described herein for any of these
products are for illustrative purposes only. NXP Semiconductors makes no
representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Customers are responsible for the design and operation of their applications
and products using NXP Semiconductors products, and NXP Semiconductors
accepts no liability for any assistance with applications or customer product
design. It is customer’s sole responsibility to determine whether the NXP
Semiconductors product is suitable and fit for the customer’s applications and
products planned, as well as for the planned application and use of
customer’s third party customer(s). Customers should provide appropriate
design and operating safeguards to minimize the risks associated with their
applications and products.
NXP Semiconductors does not accept any liability related to any default,
damage, costs or problem which is based on any weakness or default in the
customer’s applications or products, or the application or use by customer’s
third party customer(s). Customer is responsible for doing all necessary
testing for the customer’s applications and products using NXP
Semiconductors products in order to avoid a default of the applications and
the products or of the application or use by customer’s third party
customer(s). NXP does not accept any liability in this respect.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) will cause permanent
damage to the device. Limiting values are stress ratings only and (proper)
operation of the device at these or any other conditions above those given in
the Recommended operating conditions section (if present) or the
Characteristics sections of this document is not warranted. Constant or
repeated exposure to limiting values will permanently and irreversibly affect
the quality and reliability of the device.
Terms and conditions of commercial sale — NXP Semiconductors
products are sold subject to the general terms and conditions of commercial
sale, as published at http://www.nxp.com/profile/terms, unless otherwise
agreed in a valid written individual agreement. In case an individual
agreement is concluded only the terms and conditions of the respective
agreement shall apply. NXP Semiconductors hereby expressly objects to
applying the customer’s general terms and conditions with regard to the
purchase of NXP Semiconductors products by customer.
No offer to sell or license — Nothing in this document may be interpreted or
construed as an offer to sell products that is open for acceptance or the grant,
conveyance or implication of any license under any copyrights, patents or
other industrial or intellectual property rights.
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
30 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
Export control — This document as well as the item(s) described herein
may be subject to export control regulations. Export might require a prior
authorization from competent authorities.
Quick reference data — The Quick reference data is an extract of the
product data given in the Limiting values and Characteristics sections of this
document, and as such is not complete, exhaustive or legally binding.
Non-automotive qualified products — Unless this data sheet expressly
states that this specific NXP Semiconductors product is automotive qualified,
the product is not suitable for automotive use. It is neither qualified nor tested
in accordance with automotive testing or application requirements. NXP
Semiconductors accepts no liability for inclusion and/or use of
non-automotive qualified products in automotive equipment or applications.
In the event that customer uses the product for design-in and use in
automotive applications to automotive specifications and standards, customer
(a) shall use the product without NXP Semiconductors’ warranty of the
product for such automotive applications, use and specifications, and (b)
whenever customer uses the product for automotive applications beyond
NXP Semiconductors’ specifications such use shall be solely at customer’s
own risk, and (c) customer fully indemnifies NXP Semiconductors for any
liability, damages or failed product claims resulting from customer design and
use of the product for automotive applications beyond NXP Semiconductors’
standard warranty and NXP Semiconductors’ product specifications.
17.4 Trademarks
Notice: All referenced brands, product names, service names and trademarks
are the property of their respective owners.
18. Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
TFA9881
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 3 — 23 April 2013
© NXP B.V. 2013. All rights reserved.
31 of 32
TFA9881
NXP Semiconductors
3.4 W PDM input class-D audio amplifier
19. Contents
1
2
3
4
5
6
7
7.1
7.2
8
8.1
8.2
8.3
8.4
8.4.1
8.4.2
8.4.3
8.4.4
8.4.5
8.4.6
8.4.7
8.4.8
8.5
8.6
8.6.1
8.6.2
8.6.3
8.6.4
9
10
11
12
12.1
12.2
12.3
13
13.1
13.1.1
13.1.2
13.2
13.3
13.4
14
General description . . . . . . . . . . . . . . . . . . . . . . 1
Features and benefits . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Quick reference data . . . . . . . . . . . . . . . . . . . . . 2
Ordering information . . . . . . . . . . . . . . . . . . . . . 3
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pinning information . . . . . . . . . . . . . . . . . . . . . . 4
Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4
Functional description . . . . . . . . . . . . . . . . . . . 5
Mode selection and interfacing . . . . . . . . . . . . . 5
Digital stereo PDM audio input . . . . . . . . . . . . . 5
Power up/down sequence . . . . . . . . . . . . . . . . 6
Control settings. . . . . . . . . . . . . . . . . . . . . . . . . 7
Silence pattern recognition . . . . . . . . . . . . . . . . 7
Clip control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Gain selection . . . . . . . . . . . . . . . . . . . . . . . . . . 8
PWM slope selection . . . . . . . . . . . . . . . . . . . . 8
Dynamic Power Stage Activation (DPSA). . . . . 9
Bandwidth extension. . . . . . . . . . . . . . . . . . . . . 9
Mute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Power-down . . . . . . . . . . . . . . . . . . . . . . . . . . 10
High-pass filter . . . . . . . . . . . . . . . . . . . . . . . . 11
Protection mechanisms . . . . . . . . . . . . . . . . . 11
Invalid Data Protection (IDP) . . . . . . . . . . . . . 11
OverTemperature Protection (OTP) . . . . . . . . 11
Supply voltage protection mechanisms
(UVP and OVP) . . . . . . . . . . . . . . . . . . . . . . . 12
OverCurrent Protection (OCP) . . . . . . . . . . . . 12
Internal circuitry. . . . . . . . . . . . . . . . . . . . . . . . 13
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 14
Thermal characteristics . . . . . . . . . . . . . . . . . 14
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . 15
DC characteristics . . . . . . . . . . . . . . . . . . . . . 15
AC characteristics. . . . . . . . . . . . . . . . . . . . . . 16
PDM timing characteristics . . . . . . . . . . . . . . . 17
Application information. . . . . . . . . . . . . . . . . . 18
ElectroMagnetic Compatibility (EMC) . . . . . . . 18
Immunity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Supply decoupling and filtering. . . . . . . . . . . . 18
Typical application diagram (simplified) . . . . . 19
Curves measured in reference design
(demonstration board) . . . . . . . . . . . . . . . . . . 20
Package outline . . . . . . . . . . . . . . . . . . . . . . . . 25
15
15.1
15.2
15.3
15.3.1
15.3.2
15.3.3
15.3.4
16
17
17.1
17.2
17.3
17.4
18
19
Soldering of WLCSP packages . . . . . . . . . . .
Introduction to soldering WLCSP packages .
Board mounting . . . . . . . . . . . . . . . . . . . . . . .
Reflow soldering . . . . . . . . . . . . . . . . . . . . . .
Stand off . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Quality of solder joint . . . . . . . . . . . . . . . . . . .
Rework. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cleaning. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Revision history . . . . . . . . . . . . . . . . . . . . . . .
Legal information . . . . . . . . . . . . . . . . . . . . . .
Data sheet status . . . . . . . . . . . . . . . . . . . . . .
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . .
Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . .
Contact information . . . . . . . . . . . . . . . . . . . .
Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26
26
26
26
27
27
27
28
29
30
30
30
30
31
31
32
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section ‘Legal information’.
© NXP B.V. 2013.
All rights reserved.
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
Date of release: 23 April 2013
Document identifier: TFA9881
Similar pages