Data Sheet

SA58670A
2.1 W/channel stereo class-D audio amplifier
Rev. 02 — 23 October 2008
Product data sheet
1. General description
The SA58670A is a stereo, filter-free class-D audio amplifier which is available in an
HVQFN20 package with the exposed Die Attach Paddle (DAP).
The SA58670A features independent shutdown controls for each channel. The gain may
be set at 6 dB, 12 dB, 18 dB or 24 dB with gain select pins G0 and G1. Improved immunity
to noise and RF rectification is increased by high PSRR and differential circuit topology.
Fast start-up time and small package makes it an ideal choice for both cellular handsets
and PDAs.
The SA58670A delivers 1.4 W/channel at 5.0 V and 720 mW/channel at 3.6 V into 8 Ω. It
delivers 2.1 W/channel at 5.0 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 SA58670A provides thermal and
short-circuit shutdown protection.
2. Features
n Output power:
u 2.1 W/channel into 4 Ω at 5.0 V
u 1.4 W/channel into 8 Ω at 5.0 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 4 mm × 4 mm HVQFN20 package
n Low junction to ambient thermal resistance of 24 K/W with exposed DAP
3. Applications
n
n
n
n
n
Wireless and cellular handset and PDA
Portable DVD player
USB speaker
Notebook PC
Portable radio and gaming
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
n Educational toy
4. Ordering information
Table 1.
Ordering information
Type number
SA58670ABS
Package
Name
Description
Version
HVQFN20
plastic thermal enhanced very thin quad flat package;
no leads; 20 terminals; body 4 × 4 × 0.85 mm
SOT917-1
5. Block diagram
3, 13 PVDD
SA58670A
right input
INRP
INRN
n.c.
left input
INLP
INLN
G0
G1
SDR
16
17
14 OUTRP
GAIN
ADJUST
6, 10
20
19
PWM
HBRIDGE
INTERNAL
OSCILLATOR
11 OUTRN
GND
2 OUTLP
GAIN
ADJUST
PWM
HBRIDGE
15
1
8
5 OUTLN
9 AVDD
300 kΩ
SDL
VDD
BIAS
CIRCUITRY
VDD
SHORT-CIRCUIT
PROTECTION
7
4, 12
300 kΩ
18
PGND
AGND
002aad663
Refer to Table 6 for gain selection.
Fig 1.
Block diagram
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
2 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
6. Pinning information
5
17 INRN
18 AGND
16 INRP
13 PVDD
12 PGND
DAP(1)
n.c.
11 OUTRN
n.c. 10
4
AVDD
PGND
OUTLN
14 OUTRP
SA58670ABS
9
3
8
2
PVDD
7
OUTLP
15 G0
SDL
1
6
G1
SDR
terminal 1
index area
19 INLN
20 INLP
6.1 Pinning
002aad664
Transparent top view
(1) Exposed Die Attach Paddle (DAP).
Fig 2.
Pin configuration for HVQFN20
6.2 Pin description
Table 2.
Pin description
Symbol
Pin
Description
G1
1
gain select input 1
OUTLP
2
left channel positive output
PVDD
3
power supply voltage (level same as AVDD)
PGND
4
power ground
OUTLN
5
left channel negative output
n.c.
6
not connected
SDL
7
left channel shutdown input (active LOW)
SDR
8
right channel shutdown input (active LOW)
AVDD
9
analog supply voltage (level same as PVDD)
n.c.
10
not connected
OUTRN
11
right channel negative output
PGND
12
power ground
PVDD
13
power supply voltage (level same as AVDD)
OUTRP
14
right channel positive output
G0
15
gain select input 0
INRP
16
right channel positive input
INRN
17
right channel negative input
AGND
18
analog ground
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
3 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
Table 2.
Pin description …continued
Symbol
Pin
Description
INLN
19
left channel negative input
INLP
20
left channel positive input
-
(DAP)
exposed die attach paddle; connect to ground plane heat spreader
7. Limiting values
Table 3.
Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).[1]
Symbol
Parameter
Conditions
Min
Max
Unit
VDD
supply voltage
Active mode
−0.3
+6.0
V
Shutdown mode
−0.3
+7.0
V
input voltage
VI
P
power dissipation
pin SDL
GND
VDD
V
pin SDR
GND
VDD
V
other pins
−0.3
VDD + 0.3
V
Tamb = 25 °C
-
5.2
W
Tamb = 75 °C
-
3.12
W
Tamb = 85 °C
-
2.7
W
derating factor 41.6 mW/K
Tamb
ambient temperature
operating in free air
−40
+85
°C
Tj
junction temperature
operating
−40
+150
°C
Tstg
storage temperature
−65
+85
°C
Vesd
electrostatic discharge
voltage
human body model
±2000
-
V
machine model
±200
-
V
[1]
VDD is the supply voltage on pins PVDD and pin AVDD.
GND is the voltage ground on pins PGND and pin AGND.
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
4 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
8. Static characteristics
Table 4.
Static characteristics
Tamb = 25 °C; unless otherwise specified[1].
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
VDD
supply voltage
operating
2.5
-
5.5
V
IDD
supply current
VDD = 2.5 V; no load
-
4
6
mA
VDD = 3.6 V; no load
-
5
7.5
mA
VDD = 5.5 V; no load
-
6
9
mA
IDD(sd)
shutdown mode supply current
no input signal;
VSDR = VSDL = GND
-
10
1000
nA
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
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
VDD = 2.5 V
-
700
-
mΩ
VDD = 3.6 V
-
570
-
mΩ
VDD = 5.5 V
-
500
-
mΩ
measured differentially; inputs
AC grounded; Gv(cl) = 6 dB;
VDD = 2.5 V to 5.5 V
-
5
10
mV
-
2
-
kΩ
Pins OUTLP, OUTLN, OUTRP and OUTRN
RDSon
drain-source on-state resistance
|VO(offset)|
output offset voltage
Zo(sd)
shutdown mode output impedance VSDR = VSDL = 0.35 V
[1]
VDD is the supply voltage on pins PVDD and pin AVDD.
GND is the ground supply voltage on pins PGND and pin AGND.
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
5 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
9. Dynamic characteristics
Table 5.
Dynamic characteristics
Tamb = 25 °C; RL = 8 Ω; unless otherwise specified[1].
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 = 3.6 V
-
0.72
-
W
RL = 8 Ω; VDD = 5.0 V
-
1.4
-
W
RL = 4 Ω; VDD = 5.0 V
-
2.1
-
W
Po = 0.5 W
-
0.11
-
%
Po = 1.0 W
-
0.14
-
%
-
−73
-
dB
VDD = 5.0 V; Gv(cl) = 6 dB; f = 1 kHz
Gv(cl) = 6 dB; f = 217 Hz
VDD = 3.6 V
-
−77
-
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 = 5.0 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
[1]
VDD is the supply voltage on pins PVDD and pin AVDD.
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
6 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
10. Typical performance curves
001aah484
102
THD+N
(%)
10
(1)
(2)
(3)
1
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
a. Gv(cl) = 24 dB
001aah485
102
THD+N
(%)
10
(1)
(2)
(3)
1
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
b. Gv(cl) = 6 dB.
fi = 1 kHz.
(1) VDD = 2.5 V.
(2) VDD = 3.6 V.
(3) VDD = 5.0 V.
Fig 3.
Total harmonic distortion-plus-noise as a function of output power; RL = 8 Ω
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
7 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
001aah486
102
THD+N
(%)
10
(1)
(2)
(3)
1
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
a. Gv(cl) = 24 dB.
001aah487
102
THD+N
(%)
10
(1)
(2)
(3)
1
10−1
10−2
10−5
10−4
10−3
10−2
10−1
1
10
Po (W)
b. Gv(cl) = 6 dB.
fi = 1 kHz.
(1) VDD = 2.5 V.
(2) VDD = 3.6 V.
(3) VDD = 5.0 V.
Fig 4.
Total harmonic distortion-plus-noise as a function of output power; RL = 4 Ω
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
8 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
001aah488
1
THD+N
(%)
10−1
(1)
(2)
(3)
10−2
10−3
10
102
103
104
105
f (Hz)
(1) Po = 350 mW; Vi = 590 mV (RMS).
(2) Po = 240 mW; Vi = 490 mV (RMS).
(3) Po = 120 mW; Vi = 346 mV (RMS).
a. RL = 4 Ω
001aah489
1
THD+N
(%)
(1)
10−1
(2)
(3)
10−2
10−3
10
102
103
104
105
f (Hz)
(1) Po = 260 mW; Vi = 721.1 mV (RMS).
(2) Po = 180 mW; Vi = 600 mV (RMS).
(3) Po = 90 mW; Vi = 424.3 mV (RMS).
b. RL = 8 Ω
Gv(cl) = 6 dB.
Fig 5.
Total harmonic distortion-plus-noise as a function of frequency; VDD = 2.5 V
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
9 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
001aah490
1
THD+N
(%)
(1)
10−1
(3)
(2)
10−2
10−3
10
102
103
104
105
f (Hz)
(1) Po = 825 mW; Vi = 908.3 mV (RMS).
(2) Po = 550 mW; Vi = 741.6 mV (RMS).
(3) Po = 275 mW; Vi = 524.4 mV (RMS).
a. RL = 4 Ω
001aah491
1
THD+N
(%)
(1)
10−1
(2)
(3)
10−2
10−3
10
102
103
104
105
f (Hz)
(1) Po = 560 mW; Vi = 1.058 V (RMS).
(2) Po = 375 mW; Vi = 866 mV (RMS).
(3) Po = 190 mW; Vi = 616.4 mV (RMS).
b. RL = 8 Ω
Gv(cl) = 6 dB.
Fig 6.
Total harmonic distortion-plus-noise as a function of frequency; VDD = 3.6 V
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
10 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
001aah492
1
THD+N
(%)
10−1
(1)
10−2
(2)
(3)
10−3
10
102
103
104
105
f (Hz)
(1) Po = 1.65 W; Vi = 1.285 V (RMS).
(2) Po = 1.1 W; Vi = 1.05 V (RMS).
(3) Po = 550 mW; Vi = 741.6 mV (RMS).
a. RL = 4 Ω
001aah493
10
THD+N
(%)
(1)
1
10−1
(2)
(3)
10−2
10−3
10
102
103
104
105
f (Hz)
(1) Po = 1.16 W; Vi = 1.523 V (RMS).
(2) Po = 775 mW; Vi = 1.245 V (RMS).
(3) Po = 380 mW; Vi = 871.8 mV (RMS).
b. RL = 8 Ω
Gv(cl) = 6 dB.
Fig 7.
Total harmonic distortion-plus-noise as a function of frequency; VDD = 5.0 V
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
11 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
001aah495
−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 8.
Crosstalk (stepped all-to-one) as a function of frequency
001aah497
10−3
Vn(o)
(V)
10−4
(1)
(2)
10−5
10−6
10
102
103
104
f (Hz)
(1) Left channel.
(2) Right channel.
Fig 9.
Noise output voltage (RMS value) as a function of frequency
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
12 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
001aah505
−60
αct
(dB)
−80
(1)
(2)
(3)
−100
−120
2
4
6
8
10
12
14
16
20
18
f (kHz)
a. RL = 4 Ω
001aah506
−60
αct
(dB)
−80
(1)
(2)
−100
(3)
−120
2
4
6
8
10
12
14
16
20
18
f (kHz)
b. RL = 8 Ω
(1) VDD = 2.5 V.
(2) VDD = 3.6 V.
(3) VDD = 5.0 V.
Fig 10. Crosstalk (one-to-one) as a function of frequency
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
13 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
001aah507
6
VDD
(V)
001aah508
5.5
(1)
(2)
IDD
(mA)
5V
4
(3)
4.5
3.6 V
2.5 V
2
3.5
0
0
1
2
3
2.5
2.5
3.5
4.5
VSDR; VSDL (V)
5.5
VDD (V)
(1) left channel; RL = 8 Ω.
(2) right channel; RL = 4 Ω.
(3) right channel; RL = 8 Ω.
Fig 11. Supply voltage as a function of shutdown
voltage
001aah509
1600
Fig 12. Supply current as a function of supply voltage
001aah510
800
IDD
(mA)
IDD
(mA)
1200
600
800
400
(1)
(1)
(2)
(2)
(3)
(3)
200
400
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 = 2.5 V.
(2) VDD = 3.6 V.
(3) VDD = 5.0 V.
Fig 13. Supply current as a function of output power
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
14 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
001aah511
0.8
(1)
P
(W)
001aah512
0.4
P
(W)
(1)
0.3
0.6
(2)
0.2
0.4
(2)
(3)
0.1
0.2
(3)
0
0
0
0.4
0.8
1.2
1.6
2.0
0
0.4
0.8
1.2
Po (W)
1.6
Po (W)
a. RL = 4 Ω
b. RL = 8 Ω
(1) VDD = 5.0 V.
(2) VDD = 3.6 V.
(3) VDD = 2.5 V.
Fig 14. Power dissipation as a function of output power
001aah513
100
001aah514
100
ηpo
ηpo
80
80
(1)
(2)
(3)
60
(1)
(3)
(2)
60
40
40
20
20
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 = 5.0 V.
(2) VDD = 3.6 V.
(3) VDD = 2.5 V.
Fig 15. Output power efficiency as a function of output power
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
15 of 24
SA58670A
NXP Semiconductors
2.1 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
OUTLN
FB
SA58670A
OUTRN
1 nF
1 nF
VDD
PVDD
10 µF
VDD
PVDD
1 µF
1 µF
PGND
10 µF
PGND
SDL
SDR
AVDD
VDD
1 µF
10 µF
002aad665
Fig 16. SA58670A application schematic
11.1 Power supply decoupling considerations
The SA58670A is a stereo class-D audio amplifier that requires proper supply voltage
decoupling to ensure the rated performance for THD+N and power efficiency. To decouple
high frequency transients, supply voltage spikes and digital noise on the supply voltage
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 SA58670A. It is important to place the
decoupling capacitor at the supply voltage pins of the SA58670A because any resistance
or inductance in the PCB trace between the SA58670A 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 supply voltage connection on the PCB to filter low frequency signals. Usually
this is not required due to high PSRR of the SA58670A.
11.2 Input capacitor selection
The SA58670A 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 (Vi(cm)) 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)
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
16 of 24
SA58670A
NXP Semiconductors
2.1 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 2 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 SA58670A. Place all
external components very close to the SA58670A. Placing decoupling capacitors directly
at the power supply voltage pins increases efficiency because the resistance and
inductance in the trace between the SA58670A power supply voltage 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 pins (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 frequencies
(< 1 MHz) and there are long leads from amplifier to speaker, it is necessary to use an LC
output filter.
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
17 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
11.5 Efficiency and thermal considerations
The maximum ambient operating temperature depends on the heat transferring ability of
the heat spreader on the PCB layout. In Table 3 “Limiting values”, the power derating
factor is given as 41.6 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 ) = ------------------------------------------ = ---------------- = 24 K /W
derating factor
0.0416
(3)
For a maximum allowable junction temperature Tj = 150 °C and Rth(j-a) = 24 K/W and a
maximum device dissipation of 1.5 W (750 mW per channel) and for 2.1 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 – ( 24 × 1.5 ) = 114 °C
(4)
The maximum ambient temperature is 114 °C at maximum power dissipation for 5 V
supply and 4 Ω load. If the junction temperature of the SA58670A rises above 150 °C, the
thermal protection circuitry turns the SA58670A 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 SA58670A HVQFN20 package incorporates an exposed DAP that is designed to
solder the mount directly to the PCB heat spreader. By the use of thermal vias, the DAP
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 17. Test circuit
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
18 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
13. Package outline
HVQFN20: plastic thermal enhanced very thin quad flat package; no leads;
20 terminals; body 4 x 4 x 0.85 mm
B
D
SOT917-1
A
terminal 1
index area
A
E
A1
c
detail X
C
e1
e
b
6
10
y
y1 C
v M C A B
w M C
L
11
5
e
Eh
e2
1
15
terminal 1
index area
20
16
Dh
X
0
2.5
5 mm
scale
DIMENSIONS (mm are the original dimensions)
UNIT
mm
A(1)
max.
A1
b
1
0.05
0.00
0.30
0.18
c
D(1)
Dh
E(1)
Eh
0.2
4.1
3.9
2.45
2.15
4.1
3.9
2.45
2.15
e
e1
2
0.5
e2
L
v
w
y
y1
2
0.6
0.4
0.1
0.05
0.05
0.1
Note
1. Plastic or metal protrusions of 0.075 mm maximum per side are not included.
REFERENCES
OUTLINE
VERSION
IEC
JEDEC
JEITA
SOT917 -1
---
MO-220
---
EUROPEAN
PROJECTION
ISSUE DATE
05-10-08
05-10-31
Fig 18. Package outline SOT917-1 (HVQFN20)
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
19 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
14. Soldering of SMD packages
This text provides a very brief insight into a complex technology. A more in-depth account
of soldering ICs can be found in Application Note AN10365 “Surface mount reflow
soldering description”.
14.1 Introduction to soldering
Soldering is one of the most common methods through which packages are attached to
Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both
the mechanical and the electrical connection. There is no single soldering method that is
ideal for all IC packages. Wave soldering is often preferred when through-hole and
Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not
suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high
densities that come with increased miniaturization.
14.2 Wave and reflow soldering
Wave soldering is a joining technology in which the joints are made by solder coming from
a standing wave of liquid solder. The wave soldering process is suitable for the following:
• Through-hole components
• Leaded or leadless SMDs, which are glued to the surface of the printed circuit board
Not all SMDs can be wave soldered. Packages with solder balls, and some leadless
packages which have solder lands underneath the body, cannot be wave soldered. Also,
leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered,
due to an increased probability of bridging.
The reflow soldering process involves applying solder paste to a board, followed by
component placement and exposure to a temperature profile. Leaded packages,
packages with solder balls, and leadless packages are all reflow solderable.
Key characteristics in both wave and reflow soldering are:
•
•
•
•
•
•
Board specifications, including the board finish, solder masks and vias
Package footprints, including solder thieves and orientation
The moisture sensitivity level of the packages
Package placement
Inspection and repair
Lead-free soldering versus SnPb soldering
14.3 Wave soldering
Key characteristics in wave soldering are:
• Process issues, such as application of adhesive and flux, clinching of leads, board
transport, the solder wave parameters, and the time during which components are
exposed to the wave
• Solder bath specifications, including temperature and impurities
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
20 of 24
SA58670A
NXP Semiconductors
2.1 W/channel stereo class-D audio amplifier
14.4 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 19) than a SnPb process, thus
reducing the process window
• Solder paste printing issues including 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). In addition, the peak temperature must be 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 and 8
Table 7.
SnPb eutectic process (from J-STD-020C)
Package thickness (mm)
Package reflow temperature (°C)
Volume (mm3)
< 350
≥ 350
< 2.5
235
220
≥ 2.5
220
220
Table 8.
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 19.
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
21 of 24
SA58670A
NXP Semiconductors
2.1 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 19. Temperature profiles for large and small components
For further information on temperature profiles, refer to Application Note AN10365
“Surface mount reflow soldering description”.
15. Abbreviations
Table 9.
Abbreviations
Acronym
Description
DAP
Die Attach Paddle
DVD
Digital Video Disc
EMI
ElectroMagnetic Interference
ESR
Equivalent Series Resistance
LC
inductor-capacitor filter
PC
Personal Computer
PCB
Printed-Circuit Board
PDA
Personal Digital Assistant
PWM
Pulse Width Modulator
USB
Universal Serial Bus
16. Revision history
Table 10.
Revision history
Document ID
Release date
Data sheet status
Change notice
Supersedes
SA58670A_2
20081023
Product data sheet
-
SA58670A_1
-
-
Modifications:
•
Table 4 “Static characteristics”:
– added IDD(sd) specification
SA58670A_1
20080220
Product data sheet
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
22 of 24
SA58670A
NXP Semiconductors
2.1 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: [email protected]
SA58670A_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 23 October 2008
23 of 24
SA58670A
NXP Semiconductors
2.1 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
14.4
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 SMD packages . . . . . . . . . . . . . . 20
Introduction to soldering . . . . . . . . . . . . . . . . . 20
Wave and reflow soldering . . . . . . . . . . . . . . . 20
Wave soldering . . . . . . . . . . . . . . . . . . . . . . . . 20
Reflow soldering . . . . . . . . . . . . . . . . . . . . . . . 21
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: 23 October 2008
Document identifier: SA58670A_2