Rohm BD5446EFV Technical Note

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Middle Power Class-D Speaker Amplifiers

Class-D Speaker Amplifier
for Digital Input

BD5446EFV

●Description

BD5446EFV is a Class D Speaker Amplifier designed for Flat-panel TVs in particular for space-saving and low-power
consumption, delivers an output power of 20W+20W. This IC employs state-of-the-art Bipolar, CMOS, and DMOS (BCD)
process technology that eliminates turn-on resistance in the output power stage and internal loss due to line resistances up
to an ultimate level. With this technology, the IC can achieve high efficiency of 87% (10W+10W output with 8Ω load). In
addition, the IC is packaged in a compact reverse heat radiation type power package to achieve low power consumption
and low heat generation and eliminates necessity of external heat-sink up to a total output power of 40W. This product
satisfies both needs for drastic downsizing, low-profile structures and many function, high quality playback of sound system.

●Features

1) BD5446EFV has two system of digital audio interface.
(I

2) Within the wide range of the power supply voltage, it is possible to operate in a single power supply. (10~26V)

3) It contributes to miniaturizing, making to the thin type, and the power saving of the system by high efficiency and low heat.

4) S/N of the system can be optimized by adjusting the gain setting among 8 steps. (20~34dB / 2dB step)

5) It has the output power limitation function that can be adjusted to an arbitrary output power.

6) The decrease in sound quality because of the change of the power supply voltage is prevented with the feedback

7) It provides with the best stereo DAC output for the headphone usage. As a result, the output of the selection of the

8) Eliminates pop noise generated when the power supply goes on/off, or when the power supply is suddenly shut off.

9) BD5446EFV is a highly reliable design to which it has various protection functions.
(High temperature protection, Under voltage protection, Output short protection, Output DC voltage protection and

●Applications

Flat Panel TVs (LCD, Plasma), Home Audio, Desktop PC, Amusement equipments, Electronic Music equipments, etc.,

2

S/LJ format, SDATA: 16 / 20 / 24bit, LRCLK: 32kHz / 44.1kHz / 48kHz, BCLK: 64fs (fixed), SYS_CLK: 256fs (fixed))

circuitry of the output. In addition, a low noise and low distortion are achieved.

digital input in two systems is possible.

High quality muting performance is realized by using the soft-muting technology.

Clock stop protection)

No.10075EBT14

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Technical Note

●Absolute maximum ratings (Ta=25℃)

Parameter

Symbol Ratings Unit Conditions

Supply voltage VCC 30 V Pin 25, 28, 29, 53, 54 *1 *2

2.0 W *3

Power dissipation Pd

4.5 W *4

6.2 W *5

Input voltage VIN -0.3 ~ 4.5 V Pin 7 ~ 18, 21 *1

Open-drain terminal voltage V

Operating temperature range T

Storage temperature range T

Maximum junction temperature T

*1 The voltage that can be applied reference to GND (Pin 6, 36, 37, 45, 46).
*2 Do not, however exceed Pd and Tjmax=150℃.
*3 70mm×70mm×1.6mm, FR4, 1-layer glass epoxy board (Copper on bottom layer 0%)

Derating in done at 16mW/℃ for operating above Ta＝25℃.
*4 70mm×70mm×1.6mm, FR4, 2-layer glass epoxy board (Copper on bottom layer 100%)
Derating in done at 36mW/℃ for operating above Ta＝25℃. There are thermal via on the board.
*5 70mm×70mm×1.6mm, FR4, 4-layer glass epoxy board (Copper on bottom layer 100%)
Derating in done at 49.6mW/℃ for operating above Ta＝25℃. There are thermal via on the board.

-0.3 ~ 30 V Pin24 *1

ERR

-25 ~ +85 ℃

opr

-55 ~ +150 ℃

stg

+150 ℃

jmax

●Operating conditions (Ta=25℃)

Parameter

Symbol Ratings Unit Conditions

Supply voltage VCC 10 ~ 26 V Pin 25, 28, 29, 53, 54 *1 *2

Minimum load impedance
(Speaker Output)

Minimum load impedance
(DAC Output)

*6 Do not, however exceed Pd.
* No radiation-proof design.

5.4 Ω *6

R

L_SP

R

20 kΩ Pin 22, 23

L_DA

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Technical Note

●Electrical characteristics

(Unless otherwise specified Ta=25℃,Vcc=13V,f=1kHz,RL_SP=8Ω,RL_DA=20kΩ,RESETX=3.3V,MUTEX=3.3V,PDX=3.3V,
Gain=20dB,fs=48kHz)

Item Symbol

Limits

Min Typ Max

Unit Conditions

Tota l ci r cu i t

Circuit current I

Circuit current
(Power down mode)
Open-drain terminal
Low level voltage

- 45 90 mA

CC1

- 1.5 3 mA

I

CC2

V

- - 0.8 V Pin 24,IO=0.5mA

ERR

Pin 25, 28, 29, 53, 54
No load
Pin 25, 28, 29, 53, 54,No load
RESETX=0V,MUTEX=0V,PDX=0V

Regulator output voltage 1 V

Regulator output voltage 2 V

5.0 5.5 6.0 V Pin 1, 27

REG_G

3.0 3.3 3.6 V Pin 5

REG_3

High level input voltage VIH 2.5 - 3.3 V Pin 7 ~ 18, 21

Low level input voltage VIL 0 - 0.8 V Pin 7 ~ 18, 21

Input current
(Input pull-down terminal)

33 66 132 µA Pin 7 ~ 18, 21,VIN = 3.3V

I

IH

Speaker Output

Maximum momentary
output power 1
Maximum momentary
output power 2

P

- 10 - W

O1

- 20 - W

P

O2

THD+n=10%
GAIN=26dB
VCC=18V, THD+n=10%
GAIN =26dB

*7

*7

Total harmonic distortion THDSP - 0.07 - % PO=1W, BW=20~20kHz *7

Crosstalk CTSP 65 80 - dB PO=1W, BW=IHF-A *7

Output noise voltage
(Sampling mode)
Residual noise voltage
(Mute mode)

PWM sampling frequency

V

- 140 280 µVrms -∞dBFS, BW=IHF-A *7

NO_SP

V

- 5 10 µVrms MUTEX=0V,-∞dBFS, BW=IHF-A *7

NOR_SP

f

- 512 - KHz fs=32kHz *7

PWM1

f

- 705.6 - KHz fs=44.1kHz *7

PWM2

f

- 768 - KHz fs=48kHz *7

PWM3

DAC Output

Maximum output voltage V

0.85 1.0 - Vrms 0dBFS,THD+n=1%

OMAX

Channel Balance CB -1 0 1 dB 0dBFS

Total harmonic distortion THDDA - 0.05 0.5 % -20dBFS,BW=20~20kHz

Crosstalk CTDA 65 80 - dB 0dBFS,BW=IHF-A

Output noise voltage V

Residual noise voltage V

*7 These items show the typical performance of device and depend on board layout, parts, and power supply.
The standard value is in mounting device and parts on surface of ROHM’s board directly.

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- 10 20 µVrms -∞dBFS, BW=IHF-A

NO_DA

- 3 10 µVrms

NOR_DA

MUTEX=0V,PDX=0V,

-∞dBFS, BW=IHF-A

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2010.05 - Rev.B

BD5446EFV

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Technical Note

●Electrical characteristic curves(VCC=13V,Ta=25℃,RL_SP=8Ω,RL_DA=20kΩ,Gain=20dB,fin=1kHz,fs=48kHz)

Measured by ROHM designed 4 layer board.

100

90
80
70
60
50
40

ICC(mA)

30
20
10

Sampling

0

8 101214161820 222426 28

VCC(V)

Fig.1 Fig.2 Fig.3

Current consumption

- Power supply voltage

Mute

44
40
36
32
28
24
20
16
12

8

OUTPUT POWER(W/ch)

4
0

8 10 121416 18202224 2628

THD=10%

THD=1%

VCC(V)

Output power

- Power supply voltage

3

VCC=13V

2

ICC(A)

1

0

0 5 10 15 20 25 30 35 40

TOTAL OUTPUT POWER(W)

Current consumption

ut powe

- Out

100

90
80
70
60
50
40
30

EFFICIENCY(%)

20
10

0

024681012

OUTPUT POWER(W/ch)

Fig.4 Fig.5 Fig.6

Efficiency - Output power

30
28

Po=1W
L=22µH

26

C=0.47µF

24

C

=0.068µF

22
20
18
16
14

VOLTAGE G AIN( dB)

12
10

10 100 1k 10k 100k

FREQUENCY(Hz)

Voltage gain - Frequency

0

Without signal

-20

BW=20～20KHz

-40

-60

-80

-100

NOISE FFT(dBV)

-120

-140

10 100 1k 10k 100k

FREQUENCY(Hz)

FFT of Output noise voltage

100

BW=20～20KHz

10

1

THD+N(%)

0.1

0.01

0.001 0.01 0.1 1 10 100

6KHz

1KHz

100Hz

OUTPUT POWER(W)

Fig.7

THD+N - Output power

100

Po=1W
BW=20～20KHz

10

1

THD+N(%)

0.1

0.01

10 100 1k 10k 100k

FREQUENCY(Hz)

Fig.8

THD+N - Frequency

0

-10

BW=20～20KHz

-20

-30

-40

-50

-60

-70

CR OSSTALK(dB)

-80

-90

-100

0.001 0.01 0.1 1 10

OUTPUT POWER(W)

Fig.9

Crosstalk - Output power

0

-10

Po=1W
BW=20～20KHz

-20

-30

-40

-50

-60

-70

CR OSSTALK(dB)

-80

-90

-100

10 100 1k 10k 100k

FREQUENCY(Hz)

fin=300Hz
Po=3.3W

5V/div

2V/div

Speaker outpu

MUTEX

10ms/div

Speaker outpu

MUTEX

Fig.10 Fig.11 Fig.12

Crosstalk –Frequency

Wave form when

Releasing Soft-mute

Wave form when

Activating Soft-mute

VCC=18V

2V/div

10ms/div

fin=300Hz
Po=3.3W

5V/div

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Technical Note

●Electrical characteristic curves(VCC=18V,Ta=25℃,R

Measured by ROHM designed 4layer board.

100

90
80
70
60
50
40
30

EFFICIENCY(%)

20
10

0

0 5 10 15 20

OUTPUT POWER(W/ch)

Fig.13 Fig.14 Fig.15

Efficiency – Output power

40
38
36
34
32
30
28
26

V OL TAGE G AI N(d B)

24
22
20

10 100 1k 10k 100k

Voltage gain - Frequency

100

BW=20～20KHz

10

1

THD+N(%)

0.1

0.01

0.001 0.01 0.1 1 10 100

6KHz

1KHz

100Hz

OUTPUT POWER(W)

Fig.16

THD+N - Output power

100

10

1

THD+N(%)

0.1

0.01

10 100 1k 10k 100k

0

Po=1W

-10

BW=20～20KHz

-20

-30

-40

-50

-60

-70

CR OSSTALK(dB)

-80

-90

-100

10 100 1k 10k 100k

FREQUENCY(Hz)

Fig.19

Crosstalk - Frequency

=8Ω,RL_DA=20kΩ,Gain=20dB,fin=1kHz,fs=48kHz)

L_SP

0

Po=1W
L=22µH
C=0.47µF
Cg=0.068µF

FREQUENCY(Hz)

-20

-40

-60

-80

-100

NOISE FFT(dBV)

-120

-140

10 100 1k 10k 100k

FFT of output noise voltage

Po=1W
BW=20～20KHz

FREQUENCY(Hz)

0

-10

-20

-30

-40

-50

-60

-70

CROSSTALK(dB)

-80

-90

-100

0.001 0.01 0.1 1 10 100

Fig.17

THD+N - Frequency

Crosstalk - Output power

Without signal
BW=20～20KHz

FREQUENCY(Hz)

BW=20～20KHz

OUTPUT POWER(W)

Fig.18

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●Pin configuration and Block diagram

1

2

3

4

REG_G1

FILP

Power
Limiter

FILA

5

6

7

REG_3

GNDA

8

I2S/LJ

9

Interface

10

11

12

13

14

15

16

17

18

Control

Interface

I2S/LJ

Selector

Gain

Selector

19

TEST

20

×8 Over
Sampling

Digital

Filter

PWM

Modulator

Driver

1P

Driver

1N

Driver

2N

VCCP1

REG_G1

GNDP1

REG_G1

REG_G2

GNDP2

Technical Note

54

53

NC

52

51

50

49

NC

48

NC

47

46

45

44

43

42

41

NC

40

39

38

37

36

NC

35

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NC

REG_G2

DAC

Selector

DAC

VCCA

High Temperature Protection

Under Voltage Protection

Clock Stop Protection

Output Short Protection

Output DC Voltage Protection

21

22

23

24

25

26

27

6/30

Driver

2P

VCCP2

REG_G2

NC

34

33

32

31

NC

30

29

28

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BD5446EFV

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Technical Note

●Pin function explanation (Provided pin voltages are typ. Values)

No. Pin name Pin voltage Pin explanation Internal equivalence circuit

53,54
28,29

Internal power supply pin for ch1 Gate driver

1

27

REG_G1
REG_G2

5.5V

Internal power supply pin for ch2 Gate driver

1

27

Please connect the capacitor.

45,46
36,37

25

Bias pin for PWM signal

2

FILP 1.75V~2.55V

2

Please connect the capacitor.

6

25

550K

3

4

PLMT 0V Power limiter setting terminal

Bias pin for Analog signal

FILA 2.5V

Please connect the capacitor.

3

400K

6

27

50K

4

50K

6

25

Internal power supply pin for Digital circuit

5

REG3 3.3V

Please connect the capacitor.

6

GNDA 0V GND pin for Analog signal －

5

500K

6

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Technical Note

No. Pin name Pin voltage Pin explanation Internal equivalence circuit

7
8

9
10
11

SYS_CLK

BCLK

LRCLK
SDATA1
SDATA2

0V Digital audio signal input pin

5

7,8,9

10,11

6

50K

12 RESETX

13 MUTEX

14

PDX

0V

15 IIS_LJ 0V

16
17
18

GAIN1
GAIN2
GAIN3

0V

Reset pin for Digital circuit
H: Reset OFF
L: Reset ON

Speaker output mute control pin
H: Mute OFF
L: Mute ON

Power down control pin
H: Power down OFF
L: Power down ON

Digital audio signal data format setting terminal

H: Left Justified format

2

S format

L: I

Gain setting terminal

Gain=20dB~34dB, 2dB step

5

12,13,14

6

5

15

6

5

16,17,18

50K

50K

50K

19
20

TEST1

TEST2

21 SEL_DAC 0V

0V

Test pin

Please connect to GND.

DAC output selection terminal

H: SDATA2 is output from the DAC
L: SDATA1 is output from the DAC

6

5

19,20

50K

6

5

21

50K

6

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Technical Note

No. Pin name Pin voltage Pin explanation Internal equivalence circuit

25

ch2 DAC output pin

22
23

OUT_DAC2

OUT_DAC1

2.5V

ch1 DAC output pin

Please connect it with the latter part circuit
through the capacitor.

22,23

50K

6

25

24 ERROR 3.3V

25 VCCA VCC

26,30
34,35
41,47

N.C. －

48,52

Error flag pin

Please connect pull-up resistor.
H: While Normal
L: While Error

Power supply pin for Analog signal

Non connection pin

24

500

6

－

－

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Technical Note

No. Pin name Pin voltage Pin explanation Internal equivalence circuit

28,29 VCCP2 Vcc Power supply pin for ch2 PWM signal

31,32 OUT2P Vcc~0V

33

BSP2P

－

Output pin of ch2 positive PWM
Please connect to Output LPF.

Boot-strap pin of ch2 positive
Please connect the capacitor.

36,37 GNDP2 0V GND pin for ch2 PWM signal

28,29

33
40

31,32
38,39

38,39 OUT2N Vcc~0V

40 BSP2N －

42 BSP1N －

43,44 OUT1N Vcc~0V

Output pin of ch2 negative PWM
Please connect to Output LPF.

Boot-strap pin of ch2 negative
Please connect the capacitor.

Boot-strap pin of ch1 negative
Please connect the capacitor.

Output pin of ch1 negative PWM
Please connect to Output LPF.

45,46 GNDP1 0V GND pin for ch1 PWM signal

49 BSP1P －

50,51 OUT1P Vcc~0V

Boot-strap pin of ch1 positive
Please connect the capacitor.

Output pin of ch1 positive PWM
Please connect to Output LPF.

36,37

53,54

42
49

43,44
50,51

45,46

53,54 VCCP1 － Power supply pin for ch1 PWM signal

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●GAIN1 pin, GAIN2 pin, GAIN3 pin function

GAIN3

(18pin)

L L L 20dB

L L H 22dB

L H L 24dB

L H H 26dB

H L L 28dB

H L H 30dB

H H L 32dB

H H H 34dB

●SEL_DAC pin function

SEL_DAC

(21pin)

L The Lch signal of SDATA1 is output The Rch signal of SDATA1 is output

H The Lch signal of SDATA2 is output The Rch signal of SDATA2 is output

●RESETX pin function

RESETX

(10pin)

L Reset ON

H Reset OFF

●RESETX pin

RESETX

(12pin)

L Reset ON

H Reset OFF

●PDX pin,MUTEX pin function

PDX

(12pin)

L L or H ON HiZ_Low

H L

H H Normal operation

●IIS_LJ pin function

IIS_LJ

(15pin)

L I2S

H Left Justified

GAIN2
(17pin)

MUTEX

(11pin)

GAIN1
(16pin)

OUT_DAC1 (23pin) OUT_DAC2 (24pin)

State of Digital block

State of Digital block

Power Down

OFF Normal operation

Digital data format

Speaker output gain

DAC output

(24,25pin)

Technical Note

PWM output

(33,34,38,39,43,44,48pin)

HiZ_Low

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Technical Note

●Input digital audio signal sampling frequency (fs) explanation

PWM sampling frequency, Soft-start, Soft-mute time, and the detection time of the DC voltage protection in the speaker
depends on sampling frequency (fs) of the digital audio input.

Sampling frequency of the

digital audio input

(fs)

PWM sampling frequency

(fpwm)

Soft-start / Soft-mute time

DC voltage protection in

the speaker detection time

32kHz 512kHz 64msec. 64msec.

44.1kHz 705.6kHz 46msec. 46msec.

48kHz 768kHz 43msec. 43msec.

●For voltage gain (Gain setting)

BD5446EFV prescribe voltage gain at speaker output (BTL output) under the definition 0dBV (1Vrms) as full scale input of
the digital audio input signal. For example, digital audio input signal = Full scale input, Gain setting = 20dB, Load resistance

= 8Ω will give speaker output (BTL output) amplitude as Vo=10Vrms. (Output power Po = Vo2/R

R

L_SP

= 12.5W )

L_SP

●Speaker output and DAC output

Digital audio input signal SDATA1 will be output to the speaker. (SDATA2 will not be output to the speaker. DAC output can
be selected either from digital audio input signal SDATA1 or SDATA2.)

●Format of digital audio input
・SYS_CLK: It is System Clock input signal.

It will input LRCLK, BCLK, SDATA1 (SDATA2) that synchronizes with this clock that are 256 times of sampling frequency
(256fs).

・LRCLK: It is L/R clock input signal.

It corresponds to 32kHz/44.1kHz/48kHz with those clock (fs) that are same to the sampling frequency (fs) .
The data of a left channel and a right channel for one sample is input to this section.

・BCLK: It is Bit Clock input signal.

It is used for the latch of data in every one bit by sampling frequency’s 64 times sampling frequency (64fs).

・SDATA1 & SDATA2: It is Data input signal.

It is amplitude data. The data length is different according to the resolution of the input digital audio data.
It corresponds to 16/ 20/ 24 bit.

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●I2S data format

LRCLK

BCLK

SDATA1

(SDATA2)

1/64fs

MSB

22 21 20 19 18 17 16 15 14

Lch

1

LSB

10 9

8 13 12 11

3

54

2

6

MSB

22 21 20 19 18 17 16 15 1413 12 11

32 clocks

Fig.20 I2S Data Format 64fs, 24 bit Data

LRCLK

BCLK

SDATA1

(SDATA2)

MSB

18 17 9 8 7 6 5

Lch

LSB

4321

Fig.21 I2S Data Format 64fs, 20 bit Data

MSB

18 1716 15 14 13 1 2 11 10

16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1

LRCLK

BCLK

SDATA1

(SDATA2)

MSB MSB

9876514 13 12 11 10

Lch

4321

LSB

Fig.22 I2S Data Format 64fs, 16 bit Data

The Low section of LRCLK becomes Lch, the High section of LRCLK becomes Rch.
After changing LRCLK, second bit becomes MSB.

●Left-justified format

LRCLK

BCLK

SDATA1

(SDATA2)

MSB

22 21 20 19 18 17 16 15 14

Lch1/64fs

10 9

32 clocks

8

3

2

6

LSB

1

54

MSB

22 21 20 19 18 17 16 15 1413 12 11

Fig.23 Left-Justified Data Format 64fs, 24 bit Data

LRCLK

BCLK

SDATA1

(SDATA2)

MSB

18 17 9 8 7 6 5

Lch

4321

LSB

MSB

18 1716 15 14 13 12 11 1 0

16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1

Fig.24 Left-Justified Data Format 64fs, 20 bit Data

LRCLK

Lch

BCLK

SDATA1

(SDATA2)

MSB MSB

9876514 13 12 11 10

4321

LSB

Fig.25 Left-Justified Data Format 64fs, 16 bit Data

9876514 13 12 11 10

The High section of LRCLK becomes Lch, the Low section of LRCLK becomes Rch.
After changing LRCLK, first bit becomes MSB.

Technical Note

Rch

10 9

87

76

54

32 clocks

Rch

Rch

9876514 13 12 11 10

4321

LSB

Rch

10 9

6

13 12 11

87

354 12

7

32 clocks

Rch

LSB

Rch

LSB

4321

LSB

3

12

LSB

LSB

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●Power supply start-up sequence

VCCA (25pin)
VCCP1 (53, 54pin)
VCCP2 (28, 29pin)

①Power up VCCA, VCCP1, VCCP2 simultaneously.

REG_3 (5pin)
REG_G1 (1pin)
REG_G2 (27pin)

Technical Note

t

REG_G1, REG_G2

REG_3

t

RESETX (12pin)

SYS_CLK (7pin)

BCLK (8pin)

LRCLK (9pin)
SDATA1 (10pin)
SDATA2 (11pin)

PDX (14pin)

OUT_DAC1 (23pin)
OUT_DAC2 (22pin)

MUTEX (13pin)

②Set RESETX to High after power up.

t

③Degital audio data communication.

t

④Set PDX to High.

t

t

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© 2010 ROHM Co., Ltd. All rights reserved.

Speaker output

⑤Set MUTEX to High.

Soft-start
43msec(fs=48kH z)

14/30

t

t

2010.05 - Rev.B

BD5446EFV

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●Power supply shut-down sequence

VCCA (25pin)
VCCP1 (53, 54pin)
VCCP2 (28, 29pin)

Technical Note

⑤Power down VCCA, VCCP1, VCCP2, simultaneously.

t

REG_3 (5pin)
REG_G1 (1pin)
REG_G2 (27pin)

RESETX (12pin)

SYS_CLK (7pin)

BCLK (8pin)

LRCLK (9pin)
SDATA1 (10pin)
SDATA2 (11pin)

PDX (14pin)

OUT_DAC1 (23pin)
OUT_DAC2 (22pin)

REG_G1, REG_G2

REG_3

④Set RESETX to Low

③Stop digital audio date signal.

②Set PDX to Low.

t

t

t

t

MUTEX (13pin)

①Set MUTEX to Low.

Soft-mute
43msec(fs=48kHz)

t

t

t

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15/30

2010.05 - Rev.B

BD5446EFV

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●About the protection function

Technical Note

Protection function Detecting & Releasing condition

Output short
protection

DC voltage protection
in the speaker

High temperature
protection

Under voltage
protection

Detecting

condition

Detecting

condition

Detecting

condition

Releasing

condition

Detecting

condition

Releasing

condition

Detecting

condition

Detecting current = 10A (TYP.)

PWM output Duty=0% or 100%
43msec(fs=48kHz) above fixed

Chip temperature to be above 150℃ (TYP.)

Chip temperature to be below 120℃ (TYP.)

Power supply voltage to be below 8V (TYP.)

Power supply voltage to be above 9V (TYP.)

No change to SYS_CLK more than 1usec (TYP.)

Clock stop protection

Releasing

condition

* The ERROR pin is Nch open-drain output.
* Once an IC is latched, the circuit is not released automatically even after an abnormal status is removed.

The following procedures ① or ② is available for recovery.
①After the MUTEX pin is made Low once, the MUTEX pin is returned to High again.
②Turning on the power supply again.

Normal input to SYS_CLK

DAC

Output

Normal

operation

Normal

operation

Normal

operation

Irregular

output

Normal

operation

PWM

Output

ERROR

Output

HiZ_Low

(Latch) L (Latch)

HiZ_Low

(Latch) L (Latch)

HiZ_Low

Normal

operation

HiZ_Low

Normal

operation

HiZ_Low

Normal

operation

H

H

H

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16/30

2010.05 - Rev.B

BD5446EFV

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Technical Note

1) High temperature protection
This IC has the high temperature protection circuit that prevents thermal reckless driving under an abnormal state for the
temperature of the chip to exceed Tjmax=150℃.

Detecting condition - It will detect when MUTE pin is set High and the temperature of the chip becomes 150℃(TYP.) or

more. The speaker output is muted through a soft-mute when detected.

Releasing condition - It will release when MUTE pin is set High and the temperature of the chip becomes 120℃(TYP.)

or less. The speaker output is outputted through a soft-start when released.

Temperature of

IC chip junction(℃)

150℃

120℃

OUT1P (50, 51pin)
OUT1N (43, 44pin)

OUT2P (31, 32pin)
OUT2N (38, 39pin)

HiZ-Low

Speaker output

Soft-mute
43msec(fs=48KHz)

Soft-start
43msec(fs=48KHz)

t

t

ERROR (24pin)

OUT_DAC1 (23pin)
OUT_DAC2 (22pin)

t

3.3V

t

t

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17/30

2010.05 - Rev.B

BD5446EFV

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Technical Note

2) Under voltage protection
This IC has the under voltage protection circuit that make speaker output mute once detecting extreme drop of the power
supply voltage.

Detecting condition – It will detect when MUTE pin is set High and the power supply voltage becomes lower than 8V.

The speaker output is muted through a soft-mute when detected.

Releasing condition – It will release when MUTE pin is set High and the power supply voltage becomes more than 9V.

The speaker output is outputted through a soft-start when released.

VCCA (25pin)
VCCP1 (53, 54pin)
VCCP2 (28, 29pin)

OUT1P (50, 51pin)
OUT1N (43, 44pin)
OUT2P (31, 32pin)

OUT2N (38, 39pin)

8V

HiZ-Low

9V

t

t

Speaker output

ERROR (24pin)

OUT_DAC1 (23pin)
OUT_DAC2 (22pin)

Soft-mute
43msec(fs=48kHz)

3.3V

Soft-start
43msec(fs=48kHz)

t

t

t

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18/30

2010.05 - Rev.B

BD5446EFV

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Technical Note

3) Clock stop protection
This IC has the clock stop protection circuit that make the speaker output mute when the SYS_CLK signal of the digital
audio input stops.

Detecting condition - It will detect when MUTE pin is set High and the SYS_CLK signal stops for about 1usec or more.

The speaker output is muted through a soft-mute when detected.

Releasing condition - It will release when MUTE pin is set High and the SYS_CLK signal returns to the normal clock

operation. The speaker output is outputted through a soft-start when released.

Clock stop Clock recover

SYS_CLK (7pin)

Protection start with
about 1μsec clock stop.

OUT1P (50, 51pin)
OUT1N (43, 44pin)

OUT2P (31, 32pin)
OUT2N (38, 39pin)

HiZ-Low

t

t

Speaker output

ERROR (24pin)

OUT_DAC1 (23pin)
OUT_DAC2 (22pin)

3.3V

Unstable

Soft-start
43msec(fs=48kHz)

t

t

t

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2010.05 - Rev.B

BD5446EFV

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Technical Note

4)Output short protection(Short to the power supply)
This IC has the PWM output short protection circuit that stops the PWM output when the PWM output is short-circuited to
the power supply due to abnormality.

Detecting condition - It will detect when MUTE pin is set High and the current that flows in the PWM output pin

becomes 10A(TYP.) or more. The PWM output instantaneously enters the state of HiZ-Low if
detected, and IC does the latch.

Releasing method - ①After the MUTEX pin is set Low once, the MUTEX pin is set High again.

②Turning on the power supply again.

Short to VCC Release from short to VCC

OUT1P (50, 51pin)
OUT1N (43, 44pin)
OUT2P (31, 32pin)
OUT2N (38, 39pin)

Over current

10A(TYP.)

PWM out ：　IC latches with HiZ-Low.

Released from latch state.

ERROR (24pin)

t

t

MUTEX（13pin）

１μsec(TYP.)

t

Latch release

t

5) Output short protection(Short to GND)
This IC has the PWM output short protection circuit that stops the PWM output when the PWM output is short-circuited to
GND due to abnormality.

Detecting condition - It will detect when MUTE pin is set High and the current that flows in the PWM output terminal

becomes 10A(TYP.) or more. The PWM output instantaneously enters the state of HiZ-Low if
detected, and IC does the latch.

Releasing method – ①After the MUTEX pin is set Low once, the MUTEX pin is set High again.

②Turning on the power supply again.

Short to GND

Release from short to

GND

OUT1P (50, 51pin)
OUT1N (43, 44pin)
OUT2P (31, 32pin)
OUT2N (38, 39pin)

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© 2010 ROHM Co., Ltd. All rights reserved.

Over current

ERROR (24pin)

MUTEX(13pin)

10A(TYP.)

１μsec(TYP.)

PWM out ：　IC latches with HiZ-Low.

20/30

Released from latch state.

Latch release

t

t

t

t

2010.05 - Rev.B

BD5446EFV

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Technical Note

6) DC voltage protection in the speaker
When the DC voltage in the speaker is impressed due to abnormality, this IC has the protection circuit where the speaker
is defended from destruction.

Detecting condition - It will detect when MUTE pin is set High or Low and PWM output Duty=0% or 100% ,

43msec(fs=48kHz) or above. Once detected, The PWM output instantaneously enters the state
of HiZ-Low, and IC does the latch.

Releasing method – ①After the MUTEX pin is set Low once, the MUTEX pin is set High again.

②Turning on the power supply again

PWM out locked duty=100% abnormal state.

Abnormal state release.

OUT1P (50, 51pin)
OUT1N (43, 44pin)

OUT2P (31, 32pin)
OUT2N (38, 39pin)

Speaker output

PWM output ：　IC latche with HiZ-Low.

Latch release state.

ERROR (24pin)

Protection start surge current
into speaker output for 43msec
(fs=48kHz) and over.

Soft-start

43msec(fs=48kHz)

t

t

MUTEX(13pin)

t

Latch release

t

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21/30

2010.05 - Rev.B

BD5446EFV

– 3p

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Technical Note

●Output power limiter function

This IC is provided with an output power limiter function to protect speakers from destruction by an excessive output.
Limiter values are freely specified by changing external resistors R1/R2 as shown in Fig-26. Fig-27 shows a speaker output
waveform that is generated with use of the output limiter function. Because the waveform is soft-clipped, unusual noises on
audible signals are significantly reduced under operation of limiter.
Use resistors with a high degree of accuracy for R1 and R2 (±1% or higher accuracy is recommended). The capacitor C is
for the noise removal of output power limitation terminal (3pin). Provide grounding with a 1µF capacitor. Specify a resistor of
10kΩ or higher resistor R1 and R2. If the output power limiter function is not used, R1, R2 and C is unnecessary. However,
connect 3pin with GNDA.

Power

Limiter

3

REG_3

5

Speaker
output

R1

R2

C

1μF

5pin

3.3V

Soft Clip

1μF

Fig-27

GNDA

Fig-26

10

9
8

7

6
5

4

3

VCC=13V, RL=8Ω, f=1kHz

2

Gain=20dB, 5pin=3.3V

OUTPUT POWER(W/ch) .

1
0

1 1.2 1.4 1.6 1 .8 2

3pin terminal vol tage [V]

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© 2010 ROHM Co., Ltd. All rights reserved.

Fig.28

Output power

in terminal voltage

22/30

2010.05 - Rev.B

BD5446EFV

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Technical Note

●Application Circuit Example(R

Digital Audio

Source

μ-con

GNDP1

GNDA

SYS_CLK (256fs)

BCLK (64fs)

LRCLK

SDATA1

SDATA2

RESETＸ

MUTEＸ

PDX

3.3V

C1

3.3μF

C2

1μF

( )
( )

C4

1μF

C5

1μF

(fs=32kHz～48kHz)

1

2

3

( )

4

5

6

7

8

9

10

11

12

13

14

15

16

17

C25D

C27

C22

C23

R24

3.3V

18

19

20

21

22

23

24

25

26

NC

27

REG_G2

VSS

VSS

OUT_DAC2

(Rch)

OUT_DAC1

(Lch)

ERROR

VCCA

GNDA

GNDA

GNDP2

C25

0.1μF

10μF

1μF

1μF

100kΩ

3.3μF

L_SP

REG_G1

FILP

Power
Limiter

FILA

REG_3

GNDA

I2S/LJ

Interface

Control

Interface

I2S/LJ

Selector

Gain

Selector

TEST

DAC

Selector

DAC

VCCA

=8Ω)

×8 Over
Sampling

Digital

Filter

PWM

Modulator

High Temperature Protection

Under Voltage Protection

Clock Stop Protection

Output Short Protection

Output DC Voltage Protection

Driver

1P

Driver

1N

Driver

2N

Driver

2P

VCCP1

VCCP2

REG_G1

GNDP1

REG_G1

REG_G2

GNDP2

REG_G2

NC

NC

NC

NC

NC

NC

NC

54

53

52

51

50

C49

1μF

49

48

C53 C53D

1μF

47

46

45

44

43

42

41

40

39

38

37

36

35

1μF

C28

34

33

1μF

C31

32

31

30

29

28

VCCP1

GNDP1

C42
1μF

1μF
C38

GNDP2

VCCP2

220μF

220μF

C28D

470pF

C50B

5.6Ω

R50B

R43B

5.6Ω
C43B

470pF

470pF

C38B

5.6Ω

R38B

R31B

5.6Ω
C31B

470pF

L50

22μH

0.068μF

GNDP1

0.068μF

22μH

L43

L38

22μH

0.068μF

GNDP2

0.068μF

22μH

L31

C50A

C43A

C38A

C31A

0.33μF
C43C

0.33μF

C31C

8Ω

Lch

(SDATA1)

8Ω

Rch

(SDATA1)

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2010.05 - Rev.B

BD5446EFV

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Technical Note

●BOM list(R

Parts Parts No. Value Company Product No.

IC U1 － ROHM BD5446EFV － － 18.5mm×9.5mm

Inductor L31, L38, L43, L50 22μH

Resistor

Capacitor

=8Ω)

L_SP

TOKO 1168ER-0001

SAGAMI DBE7210H-220M - (±20%) 10.5mm×6.4mm

R31B, R38B
R43B, R50B

C31, C38, C42, C49 1μF

C25, C28, C53 0.1μF GRM188B31H104KA92 50V B(±10%） 1.6mm×0.8mm

C31A, C38A
C43A, C50A

C31C, C43C 0.33μF GRM219B31H334KA87 50V B(±10%） 2.0mm×1.25mm

C1, C27 3.3μF GRM188B31A335KE15 10V B(±10%） 1.6mm×0.8mm

5.6Ω ROHM MCR18PZHZFL5R60 1/4W F(±1%) 3.2mm×1.6mm

GRM185B31C105KE43 16V B(±10%

0.068μF GRM21BB11H683KA01 50V B(±10%

MURATA

Rated

Voltage

Tolerance Size

- (±20%) 10.3mm×7.6mm

） 1.6mm×0.8mm

） 2.0mm×1.25mm

Electrolytic

Capacitor

C2, C4, C5

C22, C23

C31B, C38B
C43B, C50B

C28D, C53D 220μF

C25D 10μF EEUFC1H100L 50V ±20% φ5mm×11mm

1μF GRM185B30J105KE25 6.3V B(±10%

470pF GRM188B11H471KA 50V B(±10%

ECA1VMH221 35V ±20% φ8mm×11.5mm

Panasonic

） 1.6mm×0.8mm

） 2.0mm×1.2mm

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24/30

2010.05 - Rev.B

BD5446EFV

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Technical Note

●Application Circuit Example(R

Digital Audio

Source

μ-con

GNDP1

GNDA

SYS_CLK (256fs)

BCLK (64fs)

LRCLK

SDATA1

SDATA2

RESETＸ

MUTEＸ

PDX

3.3V

C1

3.3μF

C2

1μF

( )
( )

C4

1μF

C5

1μF

(fs=32kHz～48kHz)

1

2

3

( )

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

1μF

1μF

C25D

C27

C22

C23

R24

3.3V

20

21

22

23

24

25

26

NC

27

C25

0.1μF

10μF

VSS

100kΩ

3.3μF

VSS

OUT_DAC2

(Rch)

OUT_DAC1

(Lch)

ERROR

VCCA

GNDA

GNDA

GNDP2

L_SP

Power

Limiter

I2S/LJ

Interface

Control

Interface

I2S/LJ

Selector

Gain

Selector

TEST

DAC

Selector

DAC

VCCA

REG_G2

REG_G1

FILP

FILA

REG_3

GNDA

=6Ω)

×8 Over
Sampling

Digital

Filter

PWM

Modulator

High Temperature Protection

Under Voltage Protection

Clock Stop Protection

Output Short Protection

Output DC Voltage Protection

Driver

1P

Driver

1N

Driver

2N

Driver

2P

VCCP1

VCCP2

REG_G1

GNDP1

REG_G1

REG_G2

GNDP2

REG_G2

NC

NC

NC

NC

NC

NC

NC

54

53

52

51

50

C49

1μF

49

48

C53 C53D

1μF

47

46

45

44

43

42

41

40

39

38

37

36

35

1μF

C28

34

33

1μF

C31

32

31

30

29

28

VCCP1

GNDP1

C42
1μF

1μF

C38

GNDP2

VCCP2

220μF

220μF

C28D

470pF

C50B

5.6Ω

R50B

R43B

5.6Ω
C43B

470pF

470pF

C38B

5.6Ω

R38B

R31B

5.6Ω

C31B

470pF

L50

15μH

0.1μF

GNDP1

0.1μF

15μH

L43

L38

15μH

GNDP2

15μH

L31

0.1μF

0.1μF

C50A

C43A

C38A

C31A

0.47μF
C43C

0.47μF

C31C

6Ω

Lch

(SDATA1)

6Ω

Rch

(SDATA1)

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2010.05 - Rev.B

BD5446EFV

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Technical Note

●BOM list(R

Parts Parts No. Value Company Product No.

IC U1 － ROHM BD5446EFV － － 18.5mm×9.5mm

Inductor L31, L38, L43, L50 15μH SAGAMI DBE7210H-150M － (±20%) 10.5mm×6.4mm

Resistor

Capacitor

=6Ω)

L_SP

R31B, R38B
R43B, R50B

C31, C38, C42, C49 1µF

C25, C28, C53, C31A,

C38A, C43A, C48A

C31C, C43C 0.47μF GRM21BB31H474KA87 50V B(±10%） 2.0mm×1.2mm

C1, C27 3.3μF GRM188B31A335KE15 10V B(±10%） 1.6mm×0.8mm

C2, C4, C5

C22, C23

C31B, C38B

C43B, C50B

Rated

Voltage

5.6Ω ROHM MCR18PZHZFL5R60 1/4W F(±1%) 3.2mm×1.6mm

GRM185B31C105KE43 16V B(±10%

0.1μF GRM188B31H104KA92 50V B(±10%

MURATA

1μF GRM185B30J105KE25 6.3V B(±10%

470pF GRM188B11H471KA 50V B(±10%

Tolerance Size

） 1.6mm×0.8mm

） 1.6mm×0.8mm

） 1.6mm×0.8mm

） 2.0mm×1.2mm

Electrolytic

Capacitor

C28D, C53D 220μF

Panasonic

C25D 10μF EEUFC1H100L 50V ±20% φ5mm×11mm

ECA1VMH221 35V ±20% φ8mm×11.5mm

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2010.05 - Rev.B

BD5446EFV

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f

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Technical Note

●Output LC Filter Circuit

An output filter is required to eliminate radio-frequency components exceeding the audio-frequency region supplied to a
load (speaker). Because this IC uses sampling clock frequencies from 200kHz to 400kHz in the output PWM signals, the
high-frequency components must be appropriately removed.
This section takes an example of an LC type LPF shown in Fig.29, in which coil L and capacitor C compose a differential
filter with an attenuation property of -12dB/oct. A large part of switching currents flow to capacitor C, and only a small part
of the currents flow to speaker R

. This filter reduces unwanted emission this way. In addition, coil L and capacitor Cg

L

compose a filter against in-phase components, reducing unwanted emission further.
Filter constants depend on load impedances. The following are formulas to calculate values of L, C, and Cg when Q=0.707
is specified.

4 8 , 4 9

o

3 8 , 3 9

4 5 , 4 6

3 3 , 3 4

L

g

C

C

Cg

L

R

L

Cg ＝ 0 . 2 C F

L ＝

C ＝

RL2

H

4 π

C

1

2 π f C R L2

F

Fig. 29

R

: Load impedance (Ω)

L

: LPF cut off frequency (Hz)

f

C

Following presents output LC filter constants with typical load impedances.

fC = 30kHz fC = 40kHz

L C Cg RL L C Cg

R

L

6Ω 22µH 0.68µF 0.15µF 6Ω 15µH 0.47µF 0.1µF
8Ω 33µH 0.47µF 0.1µF 8Ω 22µH 0.33µF 0.068µF

16Ω 68µH 0.22µF 0.047µF 16Ω 47µH 0.15µF 0.033µF

Use coils with a low direct-current resistance and with a sufficient margin of allowable currents. A high direct-current
resistance causes power losses. In addition, select a closed magnetic circuit type product in normal cases to prevent
unwanted emission.
Use capacitors with a low equivalent series resistance, and good impedance characteristics at high frequency ranges
(100kHz or higher). Also, select an item with sufficient withstand voltage because flowing massive amount of
high-frequency currents is expected.

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2010.05 - Rev.B

BD5446EFV

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●Notes for use

1 ) Absolute maximum ratings

Use of the IC in excess of absolute maximum ratings such as the applied voltage or operating temperature range may
result in IC damage. Assumptions should not be made regarding the state of the IC (short mode or open mode) when
such damage is suffered. A physical safety measure such as a fuse should be implemented when use of the IC in a
special mode where the absolute maximum ratings may be exceeded is anticipated.

2 ) Power supply lines

As return of current regenerated by back EMF of output coil happens, take steps such as putting capacitor between
power supply and GND as a electric pathway for the regenerated current. Be sure that there is no problem with each
property such as emptied capacity at lower temperature regarding electrolytic capacitor to decide capacity value. If the
connected power supply does not have sufficient current absorption capacity, regenerative current will cause the voltage
on the power supply line to rise, which combined with the product and its peripheral circuitry may exceed the absolute
maximum ratings. It is recommended to implement a physical safety measure such as the insertion of a voltage clamp
diode between the power supply and GND pins.

3 ) GND potential(Pin 6, 36, 37, 45, 46).

Any state must become the lowest voltage about GND terminal and VSS terminal.

4 ) Input terminal

The parasitic elements are formed in the IC because of the voltage relation. The parasitic element operating causes the
wrong operation and destruction. Therefore, please be careful so as not to operate the parasitic elements by impressing
to input terminals lower voltage than GND and VSS. Please do not apply the voltage to the input terminal when the
power-supply voltage is not impressed.

5 ) Setting of heat

Use a thermal design that allows for a sufficient margin in light of the power dissipation (Pd) in actual operating conditions.
This IC exposes its frame of the backside of package. Note that this part is assumed to use after providing heat
dissipation treatment to improve heat dissipation efficiency. Try to occupy as wide as possible with heat dissipation
pattern not only on the board surface but also the backside.
Class D speaker amplifier is high efficiency and low heat generation by comparison with conventional Analog power
amplifier. However, In case it is operated continuously by maximum output power, Power dissipation (Pdiss) may exceed
package dissipation. Please consider about heat design that Power dissipation (Pdiss) does not exceed Package
dissipation (Pd) in average power (Poav). (Tjmax : Maximum junction temperature=150℃, Ta : Peripheral temperature[℃],
θja : Thermal resistance of package[℃/W], Poav : Average power[W], η : Efficiency)
Package dissipation : Pd(W)=(Tjmax - Ta)/θja
Power dissipation : Pdiss(W)= Poav ×(1/η- 1)

6 ) Actions in strong magnetic field

Use caution when using the IC in the presence of a strong magnetic field as doing so may cause the IC to malfunction.

Technical Note

7 ) Thermal shutdown circuit

This product is provided with a built-in thermal shutdown circuit. When the thermal shutdown circuit operates, the output
transistors are placed under open status. The thermal shutdown circuit is primarily intended to shut down the IC avoiding
thermal runaway under abnormal conditions with a chip temperature exceeding Tjmax = 150℃.

8 ) Shorts between pins and misinstallation

When mounting the IC on a board, pay adequate attention to orientation and placement discrepancies of the IC. If it is
misinstalled and the power is turned on, the IC may be damaged. It also may be damaged if it is shorted by a foreign
substance coming between pins of the IC or between a pin and a power supply or a pin and a GND.

9 ) Power supply on/off (Pin 25, 28, 29, 53, 54)

In case power supply is started up, RESETX(Pin 12), MUTEX(Pin 13) and PDX (Pin 14) always should be set Low. And
in case power supply is shut down, it should be set Low likewise. Then it is possible to eliminate pop noise when power
supply is turned on/off. And also, all power supply terminals should start up and shut down together.

10 ) ERROR terminal(Pin 24)

error flag is outputted when Output short protection and DC voltage protection in the speaker are operated. These flags

A
are the function which the condition of this product is shown in.

11 ) N.C. terminal(Pin 26, 30, 34, 35, 41, 47, 48, 52)

N.C. terminal (Non Connection Pin) does not connect to the inside circuit. Therefore, possible to use open.

12 ) TEST terminal(Pin 19, 20)

TEST terminal connects with ground to prevent the malfunction by external noise.

13 ) Precautions for Spealer-setting

If the impedance characteristics of the speakers at high-frequency range while increase rapidly, the IC might not have
stable-operation in the resonance frequency range of the LC-filter. Therefore, consider adding damping-circuit, etc.,
depending on the impedance of the speaker.

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2010.05 - Rev.B

BD5446EFV

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●Allowable Power Dissipation

7

6

5

4

3

2

Power Diss ipation Pd （W)

1

0

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

Measuring instrument : TH-156(Shibukawa Kuwano Electrical Instruments Co., Ltd.)
Measuring conditions : Installation on ROHM’s board
Board size : 70mm×70mm×1.6mm(with thermal via on board)
Material : FR4
・The board on exposed heat sink on the back of package are connected by soldering.

PCB① : 1-layer board(back copper foil size: 0mm×0mm), θja＝62.5℃/W
PCB② : 2-layer board(back copper foil size: 70mm×70mm),θja＝27.8℃/W
PCB③ : 4-layer board(back copper foil size: 70mm×70mm),θja＝20.2℃/W

Technical Note

PCB③ 6.2W

PCB② 4.5W

PCB① 2.0W

Ambient Temperature:Ta(℃)

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29/30

2010.05 - Rev.B

BD5446EFV

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●Ordering part number

Technical Note

B D 5 4 4 6 E F V - E 2

Part No. Part No.

HTSSOP-B54

(MAX 18.85 include BURR)

54 28

9.5±0.2

7.5±0.1

1PIN MARK

0.8

1.0MAX

0.85±0.05

0.65

0.08±0.05

18.5±0.1

(6.0)

0.22

+0.05

-

0.04

+

6°

4°

−

4°

(5.0)

0.5±0.15

271

0.08

0.08

S

S

M

+0.05

0.17

-

0.03

(Unit : mm)

Package
EFV : HTSSOP-B54

<Tape and Reel information>

Embossed carrier tape (with dry pack)Tape

Quantity

Direction
of feed

1.0±0.2

1500pcs
E2

The direction is the 1pin of product is at the upper left when you hold

()

reel on the left hand and you pull out the tape on the right hand

Reel

1pin

Order quantity needs to be multiple of the minimum quantity.

∗

Packaging and forming specification
E2: Embossed tape and reel

Direction of feed

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2010.05 - Rev.B

Notes

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No copying or reproduction of this document, in par t or in whole, is permitted without the
consent of ROHM Co.,Ltd.

The content specied herein is subject to change for improvement without notice.

The content specied herein is for the purpose of introducing ROHM's products (hereinafter
"Products"). If you wish to use any such Product, please be sure to refer to the specications,
which can be obtained from ROHM upon request.

Examples of application circuits, circuit constants and any other information contained herein
illustrate the standard usage and operations of the Products. The peripheral conditions must
be taken into account when designing circuits for mass production.

Great care was taken in ensuring the accuracy of the information specied in this document.
However, should you incur any damage arising from any inaccuracy or misprint of such
information, ROHM shall bear no responsibility for such damage.

The technical information specied herein is intended only to show the typical functions of and
examples of application circuits for the Products. ROHM does not grant you, explicitly or
implicitly, any license to use or exercise intellectual property or other rights held by ROHM and
other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the
use of such technical information.

Notice

The Products specied in this document are intended to be used with general-use electronic
equipment or devices (such as audio visual equipment, ofce-automation equipment, commu­nication devices, electronic appliances and amusement devices).

The Products specied in this document are not designed to be radiation tolerant.

While ROHM always makes efforts to enhance the quality and reliability of its Products, a
Product may fail or malfunction for a variety of reasons.

Please be sure to implement in your equipment using the Products safety measures to guard
against the possibility of physical injury, re or any other damage caused in the event of the
failure of any Product, such as derating, redundancy, re control and fail-safe designs. ROHM
shall bear no responsibility whatsoever for your use of any Product outside of the prescribed
scope or not in accordance with the instruction manual.

The Products are not designed or manufactured to be used with any equipment, device or
system which requires an extremely high level of reliability the failure or malfunction of which
may result in a direct threat to human life or create a risk of human injur y (such as a medical
instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, fuel­controller or other safety device). ROHM shall bear no responsibility in any way for use of any
of the Products for the above special purposes. If a Product is intended to be used for any
such special purpose, please contact a ROHM sales representative before purchasing.

If you intend to export or ship overseas any Product or technology specied herein that may
be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to
obtain a license or permit under the Law.

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© 2010 ROHM Co., Ltd. All rights reserved.

Thank you for your accessing to ROHM product informations.
More detail product informations and catalogs are available, please contact us.

ROHM Customer Support System

http://www.rohm.com/contact/

R1010

A