stk433-060-e Sanyo Semiconductor Corporation, stk433-060-e Datasheet - Page 9

• Manufacturer Part Number: stk433-060-e
• Description: Thick-film Hybrid 2-channel Class Audio Power 50w+50w
• Manufacturer: Sanyo Semiconductor Corporation

STK433-000 Series Application Explanation
The protection circuit application for the STK433-000sr 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) Standby control circuit block
Concerning pin 13 reference voltage VST
<1> Operation mode
<2> Standby mode
(*1) Limiting resistor
(*2) The standby control voltage must be supplied from the host including microcontrollers.
(*3) A 4.7kΩ limiting resistor is also incorporated inside the hybrid IC (at pin 13).
Determine the value of R1 so that the voltage VST applied to the standby pin (pin 13) falls within the rating
(+2.5V to 5.5V (typ. 3.0V)).
The switching transistor of the predriver IC turns off when the pin 13 reference voltage, VST, becomes lower
than or equal to 0.6V (typ. 0V), placing the amplifier into the standby mode.
Example: When VST = 0.6V
I1 is approximately equal to 0mA since VST = (*2) × IST + 0.6V → 0.6V = 4.7kΩ × IST + 0.6V.
The switching transistor of the predriver IC turns on when the pin 13 reference voltage, VST, becomes greater
than or equal to 2.5V, placing the amplifier into the operation mode.
Example: When VST (min.) = 2.5V
I1 is approximately equal to 0.40mA since VST = (*2) × IST + 0.6V → 2.5V = 4.7kΩ × IST + 0.6V.
Point.B
(2) Load short
-PRE
1
detection part
STK433-000 series
-V CC
2
56kΩ
+V CC
3
Tr1
6.8kΩ
OUT(+)
Point.C
Ch1
OUT Ch1
4
OUT(-)
56kΩ
Point.B
Ch1
5
OUT(+)
Tr2
6.8kΩ
Ch2
6
OUT Ch2
OUT(-)
Ch2
7
+PRE
Point.C
8
I2
SUB GND
9
Stand-by Circuit
in Pre Driver IC
STK433-060-E
10
0.1μF 10kΩ
82kΩ
82kΩ
Ch1
11
IN
ΔV BE
SW transistor
Tr4
22μF
22μF
Ch1
NF
12
100kΩ
1kΩ
22kΩ
ST-BY
56kΩ
13
-V CC
100
kΩ
(*4) R2
Tr3
Tr5
Ch2
14
NF
4.7kΩ (*3)
I1
Ch2
15
IN
(3) Latch-up
Tr6
circuit part
(4) DC offset
I3
ex) 5.1kΩ
protection
(*1) R1
Operate mode (VST OFF ) ≥ 2.5V
Stand-By mode (VST ON ) < 0.6V (0V typ)
Tr5
33μF
1) Stand-by control circuit part
H: Operation mode (+5V)
L: Stand-by mode (0V)
33kΩ
1kΩ
2kΩ
No. A1487-9/11
Stand-By control
Voltage VST