PHILIPS SA58671

SA58671
1.2 W/channel stereo class-D audio amplifier
Rev. 02 — 24 October 2008
Product data sheet
1. General description
The SA58671 is a stereo, filter-free class-D audio amplifier which is available in a
16 bump WLCSP (Wafer Level Chip-Size Package).
The SA58671 features independent shutdown controls for each channel. The gain can be
set at 6 dB, 12 dB, 18 dB or 24 dB using G0 and G1 gain select pins. Improved immunity
to noise and RF rectification is increased by high PSRR and differential circuit topology.
Fast start-up time and very small WLCSP package makes it an ideal choice for both
cellular handsets and PDAs.
The SA58671 delivers 1.3 W/channel at 5 V and 720 mW/channel at 3.6 V into 8 Ω. It
delivers 1.2 W/channel at 5 V into 4 Ω. The maximum power efficiency is excellent at
70 % to 74 % into 4 Ω and 84 % to 88 % into 8 Ω. The SA58671 provides thermal and
short-circuit shutdown protection.
2. Features
n Output power:
u 1.2 W/channel into 4 Ω at 5 V
u 1.3 W/channel into 8 Ω at 5 V
u 720 mW/channel into 8 Ω at 3.6 V
n Supply voltage: 2.5 V to 5.5 V
n Independent shutdown control for each channel
n Selectable gain: 6 dB, 12 dB, 18 dB and 24 dB
n High SVRR: −77 dB at 217 Hz
n Fast start-up time: 3.5 ms
n Low supply current
n Low shutdown current
n Short-circuit and thermal protection
n Space savings with 2.06 mm × 2.11 mm 16 bump WLCSP package
n Low junction to ambient thermal resistance of 110 K/W with adequate heat sinking of
WLCSP
3. Applications
n
n
n
n
Wireless and cellular handsets and PDA
Portable DVD player
USB speaker
Notebook PC
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
n Portable radio and gaming
n Educational toy
4. Ordering information
Table 1.
Ordering information
Type number
SA58671UK
Package
Name
Description
Version
WLCSP16
wafer level chip-size package; 16 bumps;
2.06 × 2.11 × 0.6 mm
SA58671UK
5. Block diagram
A2
SA58671
C4
INRP D1
right input INRN C1
PVDD
PGND
D3 OUTRP
GAIN
ADJUST
HBRIDGE
PWM
D4 OUTRN
INTERNAL
OSCILLATOR
left input
INLP A1
INLN B1
A3 OUTLP
GAIN
ADJUST
PWM
HBRIDGE
A4 OUTLN
G0 C2
G1 B2
SDR B3
D2
300 kΩ
BIAS
CIRCUITRY
SDL B4
AVDD
SHORT-CIRCUIT
PROTECTION
C3
AGND
300 kΩ
001aah390
Refer to Table 6 for gain selection.
Fig 1.
Block diagram
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
2 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
6. Pinning information
6.1 Pinning
bump A1
index area
SA58671UK
1
2
3
4
A
1
2
3
4
B
A
INLP
PVDD
C
B
INLN
G1
SDR
SDL
D
C
INRN
G0
AGND
PGND
D
INRP
AVDD
Transparent top view
OUTLP OUTLN
OUTRP OUTRN
001aah181
002aac868
Transparent top view.
Fig 2.
Pin configuration for WLCSP16
Fig 3.
Bump mapping for WLCSP16
6.2 Pin description
Table 2.
Pin description
Symbol
Pin
Description
INLP
A1
left channel positive input
INLN
B1
left channel negative input
INRN
C1
right channel negative input
INRP
D1
right channel positive input
PVDD
A2
power supply voltage (level same as AVDD)
G1
B2
gain select input 1
G0
C2
gain select input 0
AVDD
D2
analog supply voltage (level same as PVDD)
OUTLP
A3
left channel positive output
SDR
B3
right channel shutdown input (active LOW)
AGND
C3
analog ground
OUTRP
D3
right channel positive output
OUTLN
A4
left channel negative output
SDL
B4
left channel shutdown input (active LOW)
PGND
C4
power ground
OUTRN
D4
right channel negative output
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
3 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
7. Limiting values
Table 3.
Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
Parameter
Conditions
VDD
supply voltage
VI
input voltage
P
power dissipation
active mode
shutdown mode
Min
Max
Unit
−0.3
+6.0
V
−0.3
+7.0
V
−0.3
VDD + 0.3
V
derating factor
9.12 mW/K
Tamb = 25 °C
-
1.2
W
Tamb = 75 °C
-
690
mW
Tamb = 85 °C
-
600
mW
Tamb
ambient temperature
operating in free air
−40
+85
°C
Tj
junction temperature
operating
−40
+150
°C
Tstg
storage temperature
−65
+85
°C
[1]
VDD is the supply voltage on pin PVDD and pin AVDD.
SA58671_2
Product data sheet
[1]
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
4 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
8. Static characteristics
Table 4.
Static characteristics
Tamb = 25 °C; unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
VDD
supply voltage
operating
2.5
-
5.5
V
IDD
supply current
VDD = 5.5 V; no load
-
6
9
mA
VDD = 3.6 V; no load
-
5
7.5
mA
VDD = 2.5 V; no load
-
4
6
mA
IDD(sd)
shutdown mode supply current
no input signal;
VSDR = VSDL = GND
-
10
1000
nA
|VO(offset)|
output offset voltage
measured differentially;
inputs AC grounded;
Gv(cl) = 6 dB;
VDD = 2.5 V to 5.5 V
-
5
25
mV
PSRR
power supply rejection ratio
VDD = 2.5 V to 5.5 V
-
−75
−55
dB
Vi(cm)
common-mode input voltage
0.5
-
VDD − 0.8
V
CMRR
common mode rejection ratio
inputs are shorted together;
VDD = 2.5 V to 5.5 V
-
−69
−50
dB
VIH
HIGH-level input voltage
VDD = 2.5 V to 5.5 V;
pins SDL, SDR, G0, G1
1.3
-
VDD
V
VIL
LOW-level input voltage
VDD = 2.5 V to 5.5 V;
pins SDL, SDR, G0, G1
0
-
0.35
V
IIH
HIGH-level input current
VDD = 5.5 V; VI = VDD
-
-
50
µA
IIL
LOW-level input current
VDD = 5.5 V; VI = 0 V
-
-
5
µA
RDSon
drain-source on-state resistance
VDD = 5.5 V
-
500
-
mΩ
VDD = 3.6 V
-
570
-
mΩ
VDD = 2.5 V
-
700
-
mΩ
Zo(sd)
shutdown mode output impedance
VSDR = VSDL = 0.35 V
-
2
-
kΩ
fsw
switching frequency
VDD = 2.5 V to 5.5 V
250
300
350
kHz
Gv(cl)
closed-loop voltage gain
VG0 = VG1 = 0.35 V
5.5
6
6.5
dB
VG0 = VDD; VG1 = 0.35 V
11.5
12
12.5
dB
VG0 = 0.35 V; VG1 = VDD
17.5
18
18.5
dB
VG0 = VG1 = VDD
23.5
24
24.5
dB
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
5 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
9. Dynamic characteristics
Table 5.
Dynamic characteristics
Tamb = 25 °C; RL = 8 Ω; unless otherwise specified.
Symbol
Parameter
Conditions
Po
output power
per channel; f = 1 kHz; THD+N = 10 %
THD+N
SVRR
total harmonic
distortion-plus-noise
supply voltage ripple
rejection
Min
Typ
Max
Unit
RL = 8 Ω; VDD = 5.0 V
-
1.3
-
W
RL = 8 Ω; VDD = 3.6 V
-
0.72
-
W
RL = 4 Ω; VDD = 5.0 V
-
1.2
-
W
Po = 1 W
-
0.14
-
%
Po = 0.5 W
-
0.11
-
%
-
−77
-
dB
VDD = 5.0 V; Gv(cl) = 6 dB; f = 1 kHz
Gv(cl) = 6 dB; f = 217 Hz
VDD = 5.0 V
-
−73
-
dB
CMRR
common mode rejection VDD = 5.0 V; Gv(cl) = 6 dB; f = 217 Hz
ratio
-
−69
-
dB
Zi
input impedance
Gv(cl) = 6 dB
-
28.1
-
kΩ
Gv(cl) = 12 dB
-
17.3
-
kΩ
Gv(cl) = 18 dB
-
9.8
-
kΩ
Gv(cl) = 24 dB
-
5.2
-
kΩ
-
3.5
-
ms
no weighting
-
35
-
µV
A weighting
-
27
-
µV
VDD = 3.6 V
td(sd-startup)
delay time from
shutdown to start-up
VDD = 3.6 V
Vn(o)
output noise voltage
VDD = 3.6 V; f = 20 Hz to 20 kHz;
inputs are AC grounded
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
6 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
10. Typical performance curves
001aah165
−60
αct
(dB)
−80
(1)
(2)
−100
(3)
(4)
−120
103
104
105
f (Hz)
(1) VDD = 3.6 V; L channel to R channel
(2) VDD = 3.6 V; R channel to L channel
(3) VDD = 5.0 V; L channel to R channel
(4) VDD = 5.0 V; R channel to L channel
Fig 4.
Crosstalk (stepped all-to-one) as a function of frequency
001aah164
10−3
Vn(o)
(V)
10−4
(1)
(2)
10−5
10-6
10
102
103
104
105
f (Hz)
(1) Left channel
(2) Right channel
Fig 5.
RMS output noise voltage as a function of frequency
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
7 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
001aah167
102
THD+N
(%)
(1)
(2)
(3)
10
1
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
a. RL = 8 Ω
001aah168
102
THD+N
(%)
(1)
(2)
(3)
10
1
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
b. RL = 4 Ω
(1) VDD = 2.5 V
(2) VDD = 3.6 V
(3) VDD = 5.0 V
Fig 6.
Total harmonic distortion-plus-noise as a function of output power; Gv(cl) = 6 dB
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
8 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
001aah170
10
THD+N
(%)
(1)
(2)
1
(3)
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
a. VDD = 3.0 V
001aah169
10
THD+N
(%)
(1)
(2)
1
(3)
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
b. VDD = 3.6 V
001aah171
10
THD+N
(%)
(1)
(2)
1
(3)
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
c. VDD = 4.2 V
(1) fi = 1 kHz
(2) fi = 3 kHz
(3) fi = 5 kHz
Fig 7.
Total harmonic distortion-plus-noise as a function of output power; RL = 8 Ω;
Gv(cl) = 6 dB
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
9 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
001aah172
10
THD+N
(%)
1
(1)
10−1
(2)
(3)
10−2
10
102
103
104
105
f (Hz)
a. RL = 8 Ω
001aah173
10
THD+N
(%)
(1)
1
10−1
(2)
(3)
10−2
10
102
103
104
105
f (Hz)
b. RL = 4 Ω
(1) VI = 900 mV
(2) VI = 725 mV
(3) VI = 525 mV
Fig 8.
Total harmonic distortion-plus-noise as a function of frequency; VDD = 3.6 V
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
10 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
001aah174
20
FFT
(dB)
−20
−60
−100
−140
0
4
8
12
16
20
f (kHz)
a. channel 1
001aah556
20
FFT
(dB)
−20
−60
−100
−140
0
4
8
12
16
20
f (kHz)
b. channel 2
Fig 9.
FFT spectrum as a function of frequency; fi = 1 kHz; VI = 0 dB; VDD = 3.6 V;
RL = 8 Ω
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
11 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
001aah175
20
FFT
(dB)
−20
−60
−100
−140
0
4
8
12
16
20
f (kHz)
a. channel 1
001aah557
20
FFT
(dB)
−20
−60
−100
−140
0
4
8
12
16
20
f (kHz)
b. channel 2
Fig 10. FFT spectrum as a function of frequency; fi = 1 kHz; VI = −10 dB; VDD = 3.6 V;
RL = 8 Ω
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
12 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
001aah176
20
FFT
(dB)
−20
−60
−100
−140
0
4
8
12
16
20
f (kHz)
a. channel 1
001aah558
20
FFT
(dB)
−20
−60
−100
−140
0
4
8
12
16
20
f (kHz)
b. channel 2
Fig 11. FFT spectrum as a function of frequency; fi = 1 kHz; VI = −20 dB; VDD = 3.6 V;
RL = 8 Ω
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
13 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
001aah391
+20
001aah392
+20
FFT
(dB)
FFT
(dB)
−20
−20
−60
−60
−100
−100
−140
−140
0
8
16
24
0
8
f (kHz)
16
24
f (kHz)
b. VI = −10 dB
a. VI = 0 dB
001aah393
+20
FFT
(dB)
−20
−60
−100
−140
0
8
16
24
f (kHz)
c. VI = −20 dB
Fig 12. FFT spectrum as a function of frequency; fi = 3 kHz; VDD = 3.6 V; RL = 8 Ω
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
14 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
001aah177
80
ηpo
(%)
(1)
60
(2)
001aah179
100
ηpo
(%)
80
(1)
(2)
60
40
40
20
20
0
0
0
0.4
0.8
1.2
1.6
2.0
0
0.4
0.8
1.2
1.6
Po (W)
Po (W)
a. RL = 4 Ω
b. RL = 8 Ω
(1) VDD = 3.6 V
(2) VDD = 5.0 V
Fig 13. Output power efficiency as a function of output power
001aah178
1.0
P
(W)
0.8
001aah573
0.4
P
(W)
(2)
0.3
(1)
0.6
(1)
(2)
0.2
0.4
0.1
0.2
0
0
0
0.4
0.8
1.2
1.6
2.0
0
Po (W)
a. RL = 4 Ω
0.4
0.8
1.2
1.6
Po (W)
b. RL = 8 Ω
(1) VDD = 3.6 V
(2) VDD = 5.0 V
Fig 14. Power dissipation as a function of output power
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
15 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
11. Application information
differential inputs
left channel
1 µF
differential inputs
right channel
1 µF
1 µF
1 µF
VDD
VDD
INLP INLN
G1
AGND
INRN INRP
G0
FB
FB
OUTLP
OUTRP
1 nF
1 nF
FB
FB
SA58671
OUTLN
OUTRN
1 nF
1 nF
VDD
PVDD
10 µF
1 µF
PGND
SDL
SDR
AVDD
VDD
1 µF
10 µF
001aah394
Fig 15. SA58671 application schematic
11.1 Power supply decoupling considerations
The SA58671 is a stereo class-D audio amplifier that requires proper power supply
decoupling to ensure the rated performance for THD+N and power efficiency. To decouple
high frequency transients, power supply spikes and digital noise on the power bus line, a
low Equivalent Series Resistance (ESR) capacitor of typically 1 µF is placed as close as
possible to the PVDD pins of the device. It is important to place the decoupling capacitor
at the power pins of the device because any resistance or inductance in the PCB trace
between the device and the capacitor can cause a loss in efficiency. Additional decoupling
using a larger capacitor, 4.7 µF or greater, may be done on the power supply connection
on the PCB to filter low frequency signals. Usually this is not required due to high PSRR of
the device.
11.2 Input capacitor selection
The SA58671 does not require input coupling capacitors when used with a differential
audio source that is biased from 0.5 V to VDD − 0.8 V. In other words, the input signal must
be biased within the common-mode input voltage range. If high pass filtering is required or
if it is driven using a single-ended source, input coupling capacitors are required.
The 3 dB cut-off frequency created by the input coupling capacitor and the input resistors
(see Table 6) is calculated by Equation 1:
1
f –3dB = -----------------------------2π × R i × C i
(1)
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
16 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
Table 6.
Gain selection
G1
G0
Gain (V/V)
Gain (dB)
Input impedance (kΩ)
LOW
LOW
2
6
28.1
LOW
HIGH
4
12
17.3
HIGH
LOW
8
18
9.8
HIGH
HIGH
16
24
5.2
Since the value of the input decoupling capacitor and the input resistance determined by
the gain setting affects the low frequency performance of the audio amplifier, it is
important to consider this during the system design. Small speakers in wireless and
cellular phones usually do not respond well to low frequency signals, so the 3 dB cut-off
frequency may be increased to block the low frequency signals to the speakers. Not using
input coupling capacitors may increase the output offset voltage.
Equation 1 is solved for Ci:
1
C i = -------------------------------------2π × R i × f –3dB
(2)
11.3 PCB layout considerations
Component location is very important for performance of the SA58671. Place all external
components very close to the device. Placing decoupling capacitors directly at the power
supply pins increases efficiency because the resistance and inductance in the trace
between the device power supply pins and the decoupling capacitor causes a loss in
power efficiency.
The trace width and routing are also very important for power output and noise
considerations.
For high current terminals (PVDD, PGND and audio output), the trace widths should be
maximized to ensure proper performance and output power. Use at least 500 µm wide
traces.
For the input pins (INRP, INRN, INLP and INLN), the traces must be symmetrical and run
side-by-side to maximize common-mode cancellation.
11.4 Filter-free operation and ferrite bead filters
A ferrite bead low-pass filter can be used to reduce radio frequency emissions in
applications that have circuits sensitive to frequencies greater than 1 MHz. A ferrite bead
low-pass filter functions well for amplifiers that must pass FCC unintentional radiation
requirements for frequencies greater than 30 MHz. Choose a bead with high-impedance
at high frequencies and very low-impedance at low frequencies. In order to prevent
distortion of the output signal, select a ferrite bead with adequate current rating.
For applications in which there are circuits that are EMI sensitive to low frequency
(< 1 MHz) and there are long leads from amplifier to speaker, it is necessary to use an LC
output filter.
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
17 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
11.5 Efficiency and thermal considerations
The maximum ambient temperature depends on the heat transferring ability of the heat
spreader on the PCB layout. In Table 3 “Limiting values”, power dissipation, the power
derating factor is given as 9.12 mW/K. The device thermal resistance, Rth(j-a) is the
reciprocal of the power derating factor. Convert the power derating factor to Rth(j-a) by
Equation 3:
1
1
R th ( j-a ) = ------------------------------------------ = ------------------- = 110 K /W
derating factor
0.00912
(3)
For a maximum allowable junction temperature, Tj = 150 °C and Rth(j-a) = 110 K/W and a
maximum device dissipation of 0.6 W (300 mW per channel) and for 1.2 W per channel
output power, 4 Ω load, 5 V supply, the maximum ambient temperature is calculated using
Equation 4:
T amb ( max ) = T j ( max ) – ( R th ( j-a ) × P max ) = 150 – ( 110 × 0.60 ) = 84 °C
(4)
The maximum ambient temperature is 84 °C at maximum power dissipation for 5 V supply
and 4 Ω load. If the junction temperature of the SA58671 rises above 150 °C, the thermal
protection circuitry turns the device off; this prevents damage to IC. Using speakers
greater than 4 Ω further enhances thermal performance and battery lifetime by reducing
the output load current and increasing amplifier efficiency.
11.6 Additional thermal information
The SA58671 16 bump WLCSP package ground bumps are soldered directly to the PCB
heat spreader. By the use of thermal vias, the bumps may be soldered directly to a ground
plane or special heat sinking layer designed into the PCB. The thickness and area of the
heat spreader may be maximized to optimize heat transfer and achieve lowest package
thermal resistance.
12. Test information
15 µH
AP585
AUDIO
ANALYZER
INxP
OUTxP
RL
DUT
INxN
OUTxN
+
15 µH
AUX0025
30 kHz
LOW-PASS FILTER
−
POWER
SUPPLY
AP585
MEASUREMENT
INPUTS
002aad417
Fig 16. Test circuit
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
18 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
13. Package outline
WLCSP16: wafer level chip-size package; 16 bumps; 2.06 x 2.11 x 0.6 mm
A
B
D
SA58671UK
bump A1
index area
A2
A
E
A1
detail X
e1
1/2 e
C
∅v
∅w
b
e
M
M
C A B
C
y
D
e
C
e2
B
1/2 e
A
1
2
3
4
X
0
1
2 mm
scale
DIMENSIONS (mm are the original dimensions)
UNIT
A
max
A1
A2
b
D
E
e
e1
e2
v
w
y
mm
0.64
0.26
0.22
0.38
0.34
0.34
0.30
2.08
2.04
2.13
2.09
0.5
1.5
1.5
0.01
0.04
0.02
OUTLINE
VERSION
REFERENCES
IEC
JEDEC
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
07-10-11
07-10-17
SA58671UK
Fig 17. Package outline WLCSP16
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
19 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
14. Soldering of WLCSP packages
14.1 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.
14.2 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
14.3 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 18) 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 7
Table 7.
Lead-free process (from J-STD-020C)
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 18.
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
20 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo 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 18. Temperature profiles for large and small components
For further information on temperature profiles, refer to application note AN10365
“Surface mount reflow soldering description”.
14.3.1 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.
14.3.2 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.
14.3.3 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.
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
21 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo 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”.
14.3.4 Cleaning
Cleaning can be done after reflow soldering.
15. Abbreviations
Table 8.
Abbreviations
Acronym
Description
DUT
Device Under Test
DVD
Digital Video Disc
EMI
ElectroMagnetic Interference
ESR
Equivalent Series Resistance
FFT
Fast Fourier Transform
LC
inductor-capacitor filter
PC
Personal Computer
PCB
Printed-Circuit Board
PDA
Personal Digital Assistant
PSRR
Power Supply Rejection Ratio
PWM
Pulse Width Modulator
USB
Universal Serial Bus
WLCSP
Wafer Level Chip-Size Package
16. Revision history
Table 9.
Revision history
Document ID
Release date
Data sheet status
Change notice
Supersedes
SA58671_2
20081024
Product data sheet
-
SA58671_1
Modifications:
•
Table 4 “Static characteristics”:
– added “IDD(sd), shutdown mode supply current” specification
•
SA58671_1
Updated soldering information
20071221
Product data sheet
SA58671_2
Product data sheet
-
-
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
22 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo 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.
17.3 Disclaimers
General — 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.
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.
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in medical, military, aircraft,
space or life support 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 accepts 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.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) may cause permanent
damage to the device. Limiting values are stress ratings only and operation of
the device at these or any other conditions above those given in the
Characteristics sections of this document is not implied. Exposure to limiting
values for extended periods may affect device reliability.
Terms and conditions of 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, including those pertaining to warranty,
intellectual property rights infringement and limitation of liability, unless
explicitly otherwise agreed to in writing by NXP Semiconductors. In case of
any inconsistency or conflict between information in this document and such
terms and conditions, the latter will prevail.
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.
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: salesaddress[email protected]
SA58671_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 24 October 2008
23 of 24
SA58671
NXP Semiconductors
1.2 W/channel stereo class-D audio amplifier
19. Contents
1
2
3
4
5
6
6.1
6.2
7
8
9
10
11
11.1
11.2
11.3
11.4
11.5
11.6
12
13
14
14.1
14.2
14.3
14.3.1
14.3.2
14.3.3
14.3.4
15
16
17
17.1
17.2
17.3
17.4
18
19
General description . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Ordering information . . . . . . . . . . . . . . . . . . . . . 2
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Pinning information . . . . . . . . . . . . . . . . . . . . . . 3
Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 3
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 4
Static characteristics. . . . . . . . . . . . . . . . . . . . . 5
Dynamic characteristics . . . . . . . . . . . . . . . . . . 6
Typical performance curves . . . . . . . . . . . . . . . 7
Application information. . . . . . . . . . . . . . . . . . 16
Power supply decoupling considerations . . . . 16
Input capacitor selection . . . . . . . . . . . . . . . . . 16
PCB layout considerations . . . . . . . . . . . . . . . 17
Filter-free operation and ferrite bead filters. . . 17
Efficiency and thermal considerations . . . . . . 18
Additional thermal information . . . . . . . . . . . . 18
Test information . . . . . . . . . . . . . . . . . . . . . . . . 18
Package outline . . . . . . . . . . . . . . . . . . . . . . . . 19
Soldering of WLCSP packages. . . . . . . . . . . . 20
Introduction to soldering WLCSP packages . . 20
Board mounting . . . . . . . . . . . . . . . . . . . . . . . 20
Reflow soldering . . . . . . . . . . . . . . . . . . . . . . . 20
Stand off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Quality of solder joint . . . . . . . . . . . . . . . . . . . 21
Rework . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Revision history . . . . . . . . . . . . . . . . . . . . . . . . 22
Legal information. . . . . . . . . . . . . . . . . . . . . . . 23
Data sheet status . . . . . . . . . . . . . . . . . . . . . . 23
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Contact information. . . . . . . . . . . . . . . . . . . . . 23
Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
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. 2008.
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: 24 October 2008
Document identifier: SA58671_2