lv49157v Sanyo Semiconductor Corporation, lv49157v Datasheet - Page 17

• Manufacturer Part Number: lv49157v
• Description: Bi-cmos Lsi Class-d Audio Power Amplifier With Built-in Headphone Ampifier Btl 15w ? 2ch
• Manufacturer: Sanyo Semiconductor Corporation

PLC
The PLC (power level control) function is able to control the maximum index modulation by setting a value of external
PLC resistance R1 voluntarily, and prevent a PWM signal from becoming the over modulation mode. In addition, this
circuit can be use as output power limit circuit because the PLC function can set the maximum index modulation
voluntarily, and variable from 2W to 15W with output power linearly in the state that made the power supply voltage and
load resistance fixation. Because the PLC function can set the suitable rated output with the same power supply
voltage/speaker regardless of screen size in flat screen televisions by this, set can plan the commonization of the board.
Furthermore, The PLC function can reduce abnormal noise in the hard clip so that output wave pattern becomes the soft
clip when it limited output power.
Measuring condition
VD = 15V, R L = 8Ω, L = 33μH (TOKO : A7502BY-330M), C = 0.1uF,C L = 0.47μF,Ta = 25°C
* When it is used this function as output power limit, please use the high-precision resistance such as the metal film
* The value of external PLC resistance R1 please connects more than 3kΩ.
* When it is changed a value of external PLC resistance R1, please turn off an amplifier.
resistor when precision of the electricity value is necessary.
18
16
14
12
10
R1
8
6
4
2
0
0
VD = 15V
R L = 8Ω
fin = 1kHz
THD + N = 10%
2ch-Drive
AES17
2
R1 -- P O @THD + N = 10%
4
6
GND
PLC
8
13
R1 – kΩ
5
LV49157V
10
12
Setting example of the output power limit value
14
1
6
18
20
LV49157V
Function image
R1 [kΩ]
3.0
3.6
4.7
6.2
7.5
8.2
9.1
10
13
15
20
MAX. Power
Half Power
Po@10% [W]
Min. Power
No.A1567-17/30
0.694
1.073
1.982
3.642
5.562
6.855
8.591
10.64
15.32
15.94
16.01