STK433-240A-E SANYO Semiconductor, STK433-240A-E Datasheet - Page 9

• Manufacturer Part Number: STK433-240A-E
• Description: 3-channel class AB audio power IC
• Manufacturer: SANYO Semiconductor

www.DataSheet4U.com
STK433-200series Stand-by Control & Mute Control & Load-Short Protection
Application
The protection circuit application for the STK433-200(A)-Esr consists of the following blocks (blocks (1) to (4)).
(1) Standby control circuit block
(2) Load short-circuit detection block
(3) Latch-up circuit block
(4) DC voltage protection block
1) Stand-by control circuit block
Concerning pin 13 reference voltage VST
-PRE
1
STK433-200(A)-E series
(Reference example) STK433-200(A)-E series test circuit (when +5V is applied to Stand-by control.)
<1> Operation Mode
<2> Stand-By Mode
(*1) The current limiting resistor (R1) must be used to ensure that the voltage flowing into the stand-by pin (pin 13)
(*2) The pop noise level when the power is turned on can be reduced by setting the time constant with a capacitor in
(*3) Determines the time constant at which the capacitor (*2) is discharged in standby mode.
-V CC
2
(2) Load short
STK433-200(A)-E series
-PRE
When the voltage flowing into pin 13 (VST) is stopped (=0V), the switching transistor in the bias circuit turns
off, placing the amplifier into the standby mode.
does not exceed its maximum rated value VST max.
operating mode.
1
The switching transistor in the bias circuit turns on and places the amplifier into the operating mode when the
voltage flowing into pin 13 (VST) becomes 0.25V or greater.
detection part
+V CC
3
-V CC
2
OUT
Ch1
56kΩ
4
+V CC
3
Tr1
OUT
Ch1
6.8kΩ
5
OUT(+)
Ch1 OUT
Ch1
4
Point.B
OUT
Ch2
6
OUT(-)
Ch1
Point.C
5
56kΩ
OUT
Ch2
7
OUT(+)
Tr2
Ch2
6
6.8kΩ
+PRE
8
Ch2 OUT
OUT(-)
Ch2
7
SUB
9
+PRE
GND
8
10
I2
Stand-By Circuit
in PreDriver IC
SUB
9
Stand-By Circuit
in PreDriver IC
Ch1
11
IN
ΔVBE
10
GND
STK433-240A-E
Ch1
12
NF
82kΩ
82kΩ
4.7kΩ
0.1μF
11
Ch1
IN
ST-BY
10kΩ
13
ΔVBE
22μF
22μF
Tr4
SW transistor
82kΩ
12
Ch1
NF
100kΩ
22kΩ
14
Ch2
NF
56kΩ
ST-BY
13
1kΩ
100kΩ
-V CC
Ch2
15
4.7kΩ
IN
Tr5
(*4)
R2
14
Ch2
NF
Ch3
16
IST
IN
VST
15
Ch2
IN
(3) Latch-up
Ch3
Tr6
17
NF
I3
circuit part
Ch3
16
IN
OUT
Ch3
18
(4) DC offset
(*1) R1
2.7kΩ
protection
Ch3
17
NF
56kΩ 6.8kΩ
OUT
Ch3
19
OUT(+)
Ch3
Tr1
18
Ch3 OUT
OUT(-)
19
ΔVBE
Ch3
ex) VST=(V1-VBE×2)×(*2)/((*1)+(*2))+VBE
=(5V-0.6V×2)×4.7kΩ/(4.7kΩ+2.7kΩ)+0.6V
≈
3.0(V)
(*1)R1
2.7kΩ
(ex)
Operate mode (VSTOFF) ≥ 2.5V
Stand-by mode (VSTON) ≤ 0.6V (0V typ)
33μF
Point.C
Point.B
(*2)
1kΩ (*3)
33kΩ
2kΩ
1) Stand-by control circuit part
(*3)
33μF
H: Operation mode (+5V)
L: Stand-by mode (0V)
33kΩ
Stand-by Control Voltage
H: Operation Mode (+5V)
L: Stand-by Mode (0V)
1kΩ
2kΩ
No. A1490-9/10
Stand-By Control
Voltage VST