BM28723AMUV
Description of Function - continued
6
Level Diagram
V
IN G
DSP
(1)DSPGain 10
G
20
DRV
(2)DriverGain(BTL) 10
20
RL
rDS rDC
(3)Loss
2
RL
(1)
(2)
(3)
Feedback
VCCP1
VCCP2
rDS
ON
OFF
ON
LPF
LPF
rDC
rDC
RL
C
Feedback
driver
VIN
DSP
(GDSP
PWM
Modulator
FET
)
rDS
(GDRV
)
OFF
Cg
Cg
VCCP1,VCCP2
The Duty ratio of
PWM output is
different from that
of the DSP output.
VDVDD
0V
0V
PWM output
from DSP
PWM output
at FET
VCCP1,VCCP2
VCCP1,VCCP2
VDVDD
VO_DSP
0V
VO_SP
0V
DSP output signal
(It converts it into the analog signal. )
FET output signal
(It converts it into the
analog signal. )
-(VCCP1,VCCP2
)
Speaker output signal
(BTL output)
VIN
GDSP
GDRV
: I2S input level [dBFS]
: DSP gain [dB]
: Feedback driver gain [dB]
V
IN G
DSP
VO _ DSP 10
[Vrms]
20
VCCP1,VCCP2 : Power supply voltage for power amp [V]
VDVDD
RL
rDS
: Power supply voltage for DSP [V]
: Speaker load resistance [Ω]
: Output FET on resistance [Ω]
(Typ=0.23Ω)
G
DRV
VO _ SP VO _ DSP 10
RL
rDS rDC RL
20
[Vrms]
2
rDC
: Direct current resistance of coil [Ω]
V
IN G
20
G
DRV
DSP
2
10
10
RL
rDS rDC
20
2
R
L
[W]
P
O(THD1%)
RL
P
O(THD10%)=P
×1.25
O(THD1%)
[W]
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TSZ02201-0C1C0E900720-1-2
31.Aug.2018 Rev.001
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TSZ22111 • 15 • 001