Class-AB Speaker Amplifiers
1W+1W Stereo Speaker / Headphone Amplifier
BH7884EFV
No.10077EAT06
●Description The BH7884EFV is a low voltage, low noise, high output speaker and headphone amplifier drive, in which a Bi-CMOS 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℃) Parameter Supply voltage Power dissipation Storage temperature Operating temperature Ratings +6.0 1100 *1 -55 ~ +125 -10 ~ +70 Unit V mW ℃ ℃
*1 Reduced by 11 mW/℃ at 25℃ or higher, when mounting on a 70mmX70mmX1.6mm PCB board).
●Operating Conditions (Ta=25℃) Parameter Supply voltage
* This IC is not designed to be radiation-resistant.
Ratings +3.0~+5.5
Unit V
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BH7884EFV
●Electrical characteristics (Unless otherwise noted, VCC=3.3V, Ta=25℃, f=1kHz) Limits Parameter Symbol Unit Min. Typ. Max. ■1 CHIP Circuit current ACTV Circuit current SPND ■SP AMP Voltage gain1 Voltage gain2 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 Maximum output level Output noise level Cross talk Output level on mute ■BEEP AMP Output voltage level ■BIAS Output voltage level ■CTRL ACTIVE mode SUSPEND mode SP/ON mode SP/OFF mode BASS-BOOST/ON mode BASS-BOOST/OFF mode STEREO mode MONO mode ACTIVE mode MUTE mode ■PSRR Ripple rejection ratio GPR -64 dBV V11H V11L V2H V2L V4H V4L V3H V3L V10H V10L VCC-0.3 GND VCC-0.3 GND VCC-0.7 GND VCC-0.7 GND VCC-0.7 GND VCC 0.3 VCC 0.3 VCC 0.7 VCC 0.7 VCC 0.7 V V V V V V V V V V VBIAS 1.4 1.7 2.0 V No Signal VBP 0.8 1.25 Vpp GHP GHP DHP ΔGHP VOHP VNHP CTHP MTHP 2.6 -10 70 -2.0 5.6 -7 0.025 100 1.0 -98 -98 -110 8.6 -4 0.1 -80 -80 -80 dB dB % dB dBV dBV dBV dBV GSP1 GSP2 DSP VOSP VNSP CTSP MTSP 9.0 15.2 2.2 12.0 18.2 0.1 5.2 -97 -90 -102 15.0 21.2 1.0 -80 -80 -80 dB dB % dBV dBV dBV dBV IA Is 9.0 0.2 18.0 10.0 mA µA
Technical Note
Condition
No signal ACTIVE No signal SUSPEND
SE, Vin=-18dBV,RL=8Ω BTL, Vin=-18dBV 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, DHP=1%, RL=10kΩ VOL:MAX, RL=32Ω, DIN-Audio VOL:MAX, RL=32Ω,Vin=-12dBV DIN-Audio VOL:MAX, RL=32Ω,Vin=-12dBV DIN-Audio Vin=1.3dBV, f=1kHz, 20MHzLPF
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 / Bass Boost mode. Hold Voltage of 4pin. SP / Non Boost 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. f=100Hz, 0.3Vpp, SIN Input SPOUT monitor, DIN-Audio
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●Block diagram
Technical Note
Fig.1
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●Control pin settings SP MUTE PIN:2PIN H L SP ACTIVE SP MUTE SPAMP is in active state SPAMP is in suspend state STEREO/MONO PIN:3PIN H L STEREO 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 L BASS BOOST NON -BOOST For SPAMP, bass is boosted For SPAMP, bass is not boosted
Technical Note
MUTE PIN:10PIN (The SPAMP mute function is realized by connecting HP_OUT to SP_IN) H L ACTIVE MUTE HPAMP is in active state HPAMP is in mute state SUSPEND PIN:11PIN H L ACTIVE SUSPEND The IC is in active state The IC is in suspend state
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2010.06 - Rev.A
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●Equivalent circuit PIN1 SP_IN_LCH PIN2 SP_MUTE PIN3 ST/MN PIN4
Technical Note
BASS BOOST
100k
100k
100k
100k
100k
100k
PIN5
LINE_IN_LCH
PIN6
BIAS
PIN7
BEEP_IN
PIN8
LIHE_IN_RCH
50
50k 35k
50 100k
16k
47k 27k
60k
PIN9
HP_VOL
PIN10
HP_MUTE
PIN11
SUSPEND
PIN12
SP_IN_RCH
100k 1k 100k
100k
100k
100k
100k
PIN13
HP_OUT_RCH
PIN14
VCC_RCH
PIN15
BOOST_R_RCH
PIN16
SPOUT1_RCH
25k 12 7.5k
40k
16
25k
40k
15
7.5k
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2010.06 - Rev.A
BH7884EFV
Technical Note
PIN17
SPOUT2_RCH
PIN18
GND_RCH
PIN19
GND_LCH
PIN20
SPOUT2_LCH
25k
25k
7.5k
7.5k
PIN21
SPOUT1_LCH
PIN22
BOOST_R_LCH
PIN23
VCC_LCH
PIN24
HP_OUT_LCH
25k
40k 1
21
30k
7.5k
40k
22
7.5k
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BH7884EFV
●Application circuit
Technical Note
Fig.2
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●Description of operations 1) LINEIN (5,8PIN) ~ HPOUT (13,24PIN) voltage gain The voltage gain at EVRMAX is generally calculated by the following equation: 40k GHP = 20 × log （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.
Technical Note
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
*(Unit: Ω)
Vcc=5V
