TECHNICAL NOTE
Speaker /Headphone Amplifier Series
1W+1W Stereo Speaker /
Headphone Amplifier
BH7884EFV
●Description
The BH7884EFV is a low voltage, low noise, high output speaker and headphone amplifier drive, in which a BiCMOS
process is used. This IC supports: headphone amplifier gain adjustment, active/suspend switching, speaker amplifier
stereo/monaural switching, and amplifier mute switching. All functions are controllable from a microcontroller. Built-in digital
noise reduction circuits eliminate digital noise and BEEP sounds.
●Features
1) Built-in 1W+1W stereo speaker amplifier (Vcc=5V, RL=8Ω, THD=10%)
2) Built-in stereo headphone amplifier
3) Built-in bass boost function for speaker amplifier
4) Built-in low noise VCA (electronic volume) for headphone
5) Built-in mute circuit
6) Built-in standby circuit
7) Low current consumption specifications (9 mA TYP. in ACTIVE mode, 0.2 μA TYP. in SUSPEND mode)
●Applications
Notebook computers, LCD TVs, etc.
●Absolute maximum ratings(Ta=25°C)
Parameter
Supply voltage
Power dissipation
Limits
+6.0
1100 *1
Unit
V
mW
Storage temperature
-55 ～ +125
°C
Operating temperature
-10 ～ +70
°C
*1 Reduced by 11 mW/C at 25C or higher, when mounting on a 70mmX70mmX1.6mm PCB board).
●Operating range (Ta=25°C)
Parameter
Limits
Unit
Supply voltage
+3.0~+5.5
V
* This IC is not designed to be radiation-resistant.
Oct. 2005
●Electrical characteristics
(Unless otherwise noted, Vcc=3.3V, Ta=25°C, f=1kHz)
Parameter
Symbol
Specifications
Min.
Typ.
Max.
-
9.0
0.2
18.0
10.0
Unit
Condition
mA
µA
No signal ACTIVE
No signal SUSPEND
■1 CHIP
Circuit current ACTV
Circuit current SPND
■SP AMP
Voltage gain1
IA
Is
GSP1
9.0
12.0
15.0
dB
SE, Vin=-18dBV,RL=8Ω
Voltage gain2
GSP2
15.2
18.2
21.2
dB
BTL, Vin=-18dBV
Distortion
Maximum output level
Output noise level
Cross talk
Output level on mute
■HP AMP
Voltage gain 3
Voltage gain 4
Distortion
Variable width of volume
DSP
VOSP
VNSP
CTSP
MTSP
2.2
-
0.1
5.2
-97
-90
-102
1.0
-80
-80
-80
%
dBV
dBV
dBV
dBV
GHP
GHP
DHP
ΔGHP
2.6
-10
70
5.6
-7
0.025
100
8.6
-4
0.1
-
dB
dB
%
dB
Maximum output level
VoHP
-2.0
1.0
-
dBV
VOL:MAX, DHP=1%, RL=10kΩ
Output noise level
VNHP
-
-98
-80
dBV
VOL:MAX, RL=32Ω, DIN-Audio
Cross talk
CTHP
-
-98
-80
dBV
Output level on mute
MTHP
-
-110
-80
dBV
VBP
0.8
1.25
-
Vpp
Output voltage level
■CTRL
VBIAS
1.4
1.7
2.0
V
ACTIVE mode
V11H
VCC
-0.3
-
VCC
V
SUSPEND mode
V11L
GND
-
0.3
V
SP/ON mode
V2H
VCC
-0.3
-
VCC
V
SP/OFF mode
V2L
GND
-
0.3
V
BASS-BOOST/ON mode
V4H
VCC
-0.7
-
VCC
V
BASS-BOOST/OFF mode
V4L
GND
-
0.7
V
STEREO mode
V3H
VCC
-0.7
-
VCC
V
MONO mode
V3L
GND
-
0.7
V
ACTIVE mode
V10H
VCC
-0.7
-
VCC
V
MUTE mode
V10L
GND
-
0.7
V
GPR
-
-64
-
dBV
BTL, Vin=-18dBV
BTL, DSP=1%
SE, DIN-Audio
SE, Vin=-18dBV, DIN-Audio
BTL, Vin=-18dBV
VOL:MAX, RL=10kΩ,Vin=-12dBV
VOL:MAX, RL=32Ω,Vin=-12dBV
VOL:MAX, RL=32Ω,Vin=-8dBV
VOL:MIN～MAX, RL=32Ω
VOL:MAX, RL=32Ω,Vin=-12dBV
DIN-Audio
VOL:MAX, RL=32Ω,Vin=-12dBV
DIN-Audio
■BEEP AMP
Output voltage level
Vin=1.3dBV, f=1kHz, 20MHzLPF
■BIAS
No Signal
Active mode.
Hold Voltage of 11pin.
Suspend mode.
Hold Voltage of 11pin.
SP/ON mode.
Hold Voltage of 2pin.
SP/OFF mode.
Hold Voltage of 2pin.
SP/BassBoost mode.
Hold Voltage of 4pin.
SP/NonBoost mode.
Hold Voltage of 4pin.
SP/STEREO mode.
Hold Voltage of 3pin.
SP/MONO mode.
Hold Voltage of 3pin.
HP/Active mode.
Hold Voltage of 10pin.
HP/MUTE mode.
Hold Voltage of 10pin.
■PSRR
Ripple rejection ratio
2/8
f=100Hz, 0.3Vpp, SIN Input
SPOUT monitor, DIN-Audio
●Block diagram
Fig.1
●Control pin settings
SP MUTE PIN:2PIN
H
SP ACTIVE
SPAMP is in active state
L
SP MUTE
SPAMP is in suspend state
STEREO/MONO PIN:3PIN
H
STEREO
L
MONO
For SPAMP, LCH and RCH both are in active state
For SPAMP, LCH is in active state and RCH is in suspend state
BASSBOOST PIN:4PIN
H
BASS BOOST
For SPAMP, bass is boosted
L
NON -BOOST
For SPAMP, bass is not boosted
MUTE PIN:10PIN
(The SPAMP mute function is realized by connecting HP_OUT to SP_IN)
H
ACTIVE
HPAMP is in active state
L
MUTE
HPAMP is in mute state
SUSPEND PIN:11PIN
H
ACTIVE
L
SUSPEND
The IC is in active state
The IC is in suspend state
●Equivalent circuit (1 of 2)
3/8
PIN1
SP_IN_LCH
PIN2
SP
100k
PIN5
LINE_IN_LCH
50
PIN6
MUTE
100k
BIAS
50k
PIN3
ST/MN
100k
PIN7
100k
100k
BEEP_IN
HP_VOL
PIN10
PIN8
100k
LIHE_IN_RCH
47k
16k
50
100k
27k
60k
35k
PIN9
BASS
BOOST
PIN4
HP_MUTE
PIN11
100k
100k
SUSPEND
PIN12
100k
100k
SP_IN_RCH
100k
1k
100k
PIN13
HP_OUT_RCH
PIN14
VCC_RCH
PIN15
BOOST_R_RCH
40k
25k
12
7.5k
4/8
40k
16
15
PIN16
SPOUT1_RCH
25k
7.5k
●Equivalent circuit (2 of 2)
PIN17
PIN21
SPOUT2_RCH
PIN18
GND_RCH
PIN19
GND_LCH
PIN20
SPOUT2_LCH
25k
25k
7.5k
7.5k
SPOUT1_LCH
PIN22
25k
7.5k
BOOST_R_LCH
40k
1
40k
PIN23
21
VCC_LCH
PIN24
HP_OUT_LCH
30k
22
7.5k
●Application circuit
Fig.2
5/8
●Description of operations
1) LINEIN (5,8PIN)～HPOUT (13,24PIN) voltage gain
The voltage gain at EVRMAX is generally calculated by the following equation:
GHP 20 log
40k
(dB)
R5( or R8 )
The above gain attenuates according to the DC voltage of the VOL pin (9PIN).
By connecting multiple resistances (R), mixing input can be handled.
2) BEEPIN(7PIN)～HPOUT(13,24PIN)
When a pulse waveform is input at the BEEPIN pin, a pulse wave is output at HPOUT (24,13PIN).
The output level, determined by the resistance of 7PIN, has default values as follows:
HP OUT level
1Vpp<
0.5Vpp
0.25Vpp
Vcc=5V
<56k
68k
75k
Vcc=4V
<91k
110k
130k
Vcc=3.3V
<120k
160k
200k
Unit:Ω
To obtain the default setting output (approx. 1.2 Vpp output), make R7=10 kΩ.
The variation in output levels is small.
Signals below a certain level are determined to be noise, by IC internals, and are not output at HPOUT.
3) SP IN (1,12PIN)～SP OUT (21,20,16,17PIN) voltage gain
The voltage gain in BASSBOOST is generally calculated by the following equation:
GSPB 20 log
40k R 2122 (or R1615 )
(dB)
R1(or R12 )
The cut-off frequency in BASSBOOST is generally calculated by the following equation:
fCB
1
(HZ )
2πC21-22 (or C16-15 ) R21-22 (or R16-15 )
The voltage gain in NONBOOST is generally calculated by the following equation:
GSP 20 log
40 k
(dB)
R1 ( or R12 )
4) EVR control characteristic
HP AMP gain is controlled by the ratio of voltage to resistance between VCC and GND.
Note: A resistance (RN), shown above, is the resistance that is connected to pin N.
A capacitance (CN), shown above, is the capacitance that is connected to pin N.
The numeric values above are design reference values, whose values are not guaranteed.
6/8
●Operation Notes
1.
2.
3.
4.
5.
6.
7.
8.
Numbers and data in entries are representative design values and are not guaranteed values of the items.
Although ROHM is confident that the example application circuit reflects the best possible recommendations, be sure to
verify circuit characteristics for your particular application. Modification of constants for other externally connected circuits
may cause variations in both static and transient characteristics for external components as well as this Rohm IC. Allow
for sufficient margins when determining circuit constants.
Absolute maximum ratings
Use of the IC in excess of absolute maximum ratings, such as the applied voltage or operating temperature range
(Topr), 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 using
the IC at times where the absolute maximum ratings may be exceeded.
GND potential
Ensure a minimum GND pin potential in all operating conditions. Make sure that no pins are at a voltage below the
GND at any time, regardless of whether it is a transient signal or not.
Thermal design
Perform thermal design, in which there are adequate margins, by taking into account the permissible dissipation (Pd)
in actual states of use.
Short circuit between terminals and erroneous mounting
Pay attention to the assembly direction of the ICs. Wrong mounting direction or shorts between terminals, GND, or
other components on the circuits, can damage the IC.
Operation in strong electromagnetic field
Using the ICs in a strong electromagnetic field can cause operation malfunction.
Pop noise when switching power ON/OFF
To prevent pop noise when switching VCC ON/OFF or switching SUSPEND ON/OFF, use SUSPEND (11PIN=L),
HP MUTE (10PIN=L), and SUSPEND (2PIN=L) for noise control, as shown below.
{VCC OFF→ON}
1)
2)
3)
4)
5)
9.
10.
11.
12.
13.
14.
VCC
OFF
ON
ON
ON
ON
SPND
L
L
H
H
H
HPMT
L
L
L
H
H
{VCC ON→OFF}
SPMT
L
L
L
L
H
1)
2)
3)
4)
5)
VCC
OFF
ON
ON
ON
ON
SPND
H
H
H
L
L
HPMT
H
H
L
L
L
SPMT
H
L
L
L
L
Power supply bypass capacitor
Place the bypass capacitor close to the VCC～GND pins.
Mode switching
Do not apply a voltage that exceeds VCC or a voltage that is less than GND, at a control pin.
Power package
Ensure a heat dissipation by connecting the heatsink to the back of the IC and to the GND board. Ensure that the
GND area is large.
HPOUT
Connect resistance (100 Ω is recommended) to the output for SPAMP input level adjustment and to prevent
HPAMP oscillation.
Capacitive load
Do not connect a capacitive load to SPAMP or HPAMP output as it may cause oscillation.
Startup time at low temperature and reduced power
Use the following methods to eliminate longer start up time at low temperatures (less than about -10°C) and reduced
power (less than about 3.0 V):
1) Start in SPMUTE state and then cancel SPMUTE.
2) Add to transistor and resistance, as shown in the application circuit diagram.
7/8
●Selection of order type
B
H
7
8
8
4
E
E
V
F
2
Tape and Reel information
Part No.
BH7884EFV
HTSSOP-B24
<Dimension>
<Tape and Reel information>
7.8 ± 0.1
4 +6
−4
0.53 ± 0.15
1 ± 0.2
13
7.6 ± 0.2
5.6 ± 0.1
24
1
12
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)
1234
1234
1234
1234
1234
1234
+0.05
−0.04
Direction
of feed
1234
0.2
2000pcs
+0.05
0.17 −0.03
0.08 S
0.65
Embossed carrier tape
Quantity
1234
1.0Max.
0.85 ± 0.05
0.08 ± 0.05
0.325
Tape
0.08 M
Reel
(Unit:mm)
1pin
Direction of feed
※When you order , please order in times the amount of package quantity.
The contents described herein are correct as of October, 2005
The contents described herein are subject to change without notice. For updates of the latest information, please contact and confirm with ROHM CO.,LTD.
Any part of this application note must not be duplicated or copied without our permission.
Application circuit diagrams and circuit constants contained herein are shown as examples of standard use and operation. Please pay careful attention to the peripheral conditions when designing circuits and deciding
upon circuit constants in the set.
Any data, including, but not limited to application circuit diagrams and information, described herein are intended only as illustrations of such devices and not as the specifications for such devices. ROHM CO.,LTD. disclaims any
warranty that any use of such devices shall be free from infringement of any third party's intellectual property rights or other proprietary rights, and further, assumes no liability of whatsoever nature in the event of any such
infringement, or arising from or connected with or related to the use of such devices.
Upon the sale of any such devices, other than for buyer's right to use such devices itself, resell or otherwise dispose of the same, implied right or license to practice or commercially exploit any intellectual property rights or other
proprietary rights owned or controlled by ROHM CO., LTD. is granted to any such buyer.
The products described herein utilize silicon as the main material.
The products described herein are not designed to be X ray proof.
Published by
Application Engineering Group
8/8
Catalog No.05T374Be '05.10 ROHM Ⓒ
Appendix
Notes
No technical content pages of this document may be reproduced in any form or transmitted by any
means without prior permission of ROHM CO.,LTD.
The contents described herein are subject to change without notice. The specifications for the
product described in this document are for reference only. Upon actual use, therefore, please request
that specifications to be separately delivered.
Application circuit diagrams and circuit constants contained herein are shown as examples of standard
use and operation. Please pay careful attention to the peripheral conditions when designing circuits
and deciding upon circuit constants in the set.
Any data, including, but not limited to application circuit diagrams information, described herein
are intended only as illustrations of such devices and not as the specifications for such devices. ROHM
CO.,LTD. disclaims any warranty that any use of such devices shall be free from infringement of any
third party's intellectual property rights or other proprietary rights, and further, assumes no liability of
whatsoever nature in the event of any such infringement, or arising from or connected with or related
to the use of such devices.
Upon the sale of any such devices, other than for buyer's right to use such devices itself, resell or
otherwise dispose of the same, no express or implied right or license to practice or commercially
exploit any intellectual property rights or other proprietary rights owned or controlled by
ROHM CO., LTD. is granted to any such buyer.
Products listed in this document are no antiradiation design.
The products listed in this document are designed to be used with ordinary electronic equipment or devices
(such as audio visual equipment, office-automation equipment, communications devices, electrical
appliances and electronic toys).
Should you intend to use these products with equipment or devices which require an extremely high level
of reliability and the malfunction of which would directly endanger human life (such as medical
instruments, transportation equipment, aerospace machinery, nuclear-reactor controllers, fuel controllers
and other safety devices), please be sure to consult with our sales representative in advance.
It is our top priority to supply products with the utmost quality and reliability. However, there is always a chance
of failure due to unexpected factors. Therefore, please take into account the derating characteristics and allow
for sufficient safety features, such as extra margin, anti-flammability, and fail-safe measures when designing in
order to prevent possible accidents that may result in bodily harm or fire caused by component failure. ROHM
cannot be held responsible for any damages arising from the use of the products under conditions out of the
range of the specifications or due to non-compliance with the NOTES specified in this catalog.
Thank you for your accessing to ROHM product informations.
More detail product informations and catalogs are available, please contact your nearest sales office.
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Appendix1-Rev2.0