LA4628
Pin Voltages
V
CC
= 13.5 V, with 5 V applied to STBY through a 10 kΩ resistor, RL = 4 Ω, Rg = 0
Pin No.
Pin
1
2
3
4
5
6
7
IN1
DC
PRE–GND
0 V
STBY
3.21 V
ON TIME
2.32 V
IN2
POP
2.07 V
Pin voltage
1.55 V
6.63 V
1.55 V
Pin No.
Pin
8
9
10
PWR–GND2
0 V
11
12
PWR–GND1
0 V
13
14
+OUT2
6.6 V
–OUT2
6.5 V
+OUT1
6.5 V
–OUT1
6.6 V
VCC
Pin voltage
13.5 V
External Components
C1 and C4: Input capacitors. A value of 2.2 µF is recommended. Determine the polarity based on the DC potential of the
circuit connected directly to the LA4628 front end. Note that the low band response can be adjusted by
varying f with the capacitors C1 and C4.
L
C2: Decoupling capacitor (ripple filter)
C3: Sets the amplifier starting time, which will be approximately 0.6 seconds for a value of 33 µF. The starting
time is proportional to the value of this capacitor, and can be set to any desired value.
C5: Power-supply capacitor
C6, C7, C8, and C9:
Oscillation prevention capacitors. Use polyester film capacitors (Mylar capacitors) with excellent
characteristics. (Note that the series resistors R2, R3, R4, and R5 are used in conjunction with these
capacitors to achieve stable amplifier operation.) A value of 0.1 µF is recommended.
C10: Impulse noise reduction capacitor. A value of 0.47 µF is recommended. Caution is required when selecting
the value for this capacitor, since increasing its value influences the operation of the circuits that protect
against shorting the amplifier output pins to V or to ground when higher V voltages (approximately
CC
CC
16 V or higher) are used.
R1: Standby switch current limiting resistor. A value of 10 kΩ is recommended when a voltage in the range 2.5
to 13.5 V will be applied as the standby switching voltage. Note that this resistor is not optional: it must be
included.
IC Internal Characteristics and Notes
1. Standby function
500 µA or lower
• Pin 4 is the standby switch. A voltage of 2.5 V or
10 kΩ
higher must be applied through an external resistor to
turn the amplifier on.
4
R1
• If a voltage of over 13.5 V will be applied as the
standby mode switching voltage, use the following
formula to determine the value of R1 so that the
current entering at pin 4 remains under 500 µA.
Applied standby
voltage
About 1.4 V
(2 VBE
)
<applied voltage> – 1.4
R1 = —————————— – 10 kΩ
500 µA
Pin 4 Internal Equivalent Circuit
2. Muting function
• Pin 5 connects the capacitor that determines the starting time to prevent impulse noise. It can also be used to mute
the amplifier output by shorting pin 5 to ground. When this function is used, the recovery time depends on C3.
No. 6632-4/8
SANYO [ SANYO SEMICON DEVICE ]
