lv4920h Sanyo Semiconductor Corporation, lv4920h Datasheet - Page 8

• Manufacturer Part Number: lv4920h
• Description: Class-d Audio Power Amplifier Power Cell Btl 15w?2ch, 10w?2ch
• Manufacturer: Sanyo Semiconductor Corporation

Functional Descriptions
1. System Standby
2. Mute Function
The NOD_OUTSHDNB (Nch open drain) output signal is generated (Nch open drain output is turned on) when output
is shut down (except when the overcurrent protection circuit is activated). This operating condition is established when
either one of the following conditions occurs:
The built-in 5V regulator is turned on and off under control of the high/low state of the STBYB pin. When the
STBYB pin is low, the regulator will be turned off, and when that pin is high, the regulator will be turned on.
Also, the signal initializes the internal logic of the IC. When the STBYB pin is low, the internal logic is initialized,
and when the STBYB pin is high, the IC is put into normal operation.
The mute function is provided mainly to mute the output so that impulse noise will not appear in the output when the
power supply is being turned on.
2.1 Output muting
2.2 Power-on sequence
(1) Thermal shutdown circuit is activated.
(2) Low power voltage protection circuit is activated.
(3) MUTEB set low (all outputs muted)
The PWM output signal can be turned on or off by setting the MUTEB pin high or low. When the MUTEB pin is
low, the PWM output is stopped (all PWM output signals are set in the high-impedance state) and when the
MUTEB pin is high, the IC is placed in normal operation mode. Also the NOD_OUTSHDNB (Nch open drain)
signal is output for an external monitor pin.
The power-on sequence must be controlled by timing as shown below (PWM=BD mode) to minimize impulse
noise.
Note that when MUTE is released, all PWM input signals must be held low.
LV4920H
No.A0989-8/12