Ordering number : EN4376A
Thick Film Hybrid IC
STK4067
High-Output Power Amplifier
for Car Stereos (Po = 60 W typ.)
Overview
Higher output amplification of the car stereo has been
generally dependent on boosting voltage of the power
supply. The STK4067 supports low-load impedance and
is designed for up to 60 W of high output without the
need for a power supply voltage booster circuit.
• Low operating power supply voltage range (9 V to 16 V)
• Built-in muting circuit
Short attack time with muting quickly enabled
• Built-in protection circuits
Built-in thermal shutdown and overvoltage protector
Applications
• Power amplifier for car stereos
• Home karaoke systems
• Radio-cassette players
Package Dimensions
unit : mm
4131
[STK4067]
Features
• Superior heat sink capacity using IMST (insulated
metal substrate technology)
• Designed for high output while supporting low-load
impedance
x
R
L
= 1Ω 60 W typ. (EIAJ)
100 W (max.)
R
L
= 2Ω 40 W typ. (EIAJ)
70 W (max.)
40 W (max.)
z
R
L
= 4Ω 23 W typ. (EIAJ)
• Supports sufficient amplifier configurations for high
power output
• Low-load impedance driver
Supports independent or parallel speaker connections
for low-load impedance driving.
• Low distortion
THD = 0.025% typ. (V
CC
= 13.2 V, R
L
= 2Ω,
Po = 10 W, f = 1 kHz)
Compared with a monolithic IC, with a base
frequency of 100 Hz, the following is established:
secondary high frequency harmonics switches to
–58 dB, with third-order switching to –20 dB,
fourth-order to –45 dB, and fifth-order to –18 dB.
• High temperature operation
Provides guaranteed high output to the passenger
compartments protected interior even when operating
in excessive heat
• Compact heat sink mounting
Supports compact total-set packaging, occupying 1/3
the heat sink area compared of monolithic ICs, and
equipped with an 85°C temperature range and 110°C
guaranteed case temperature rating
SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN
D3096HA (OT)/31293YO 5-2987 No. 4376-1/8
STK4067
Specifications
Maximum Ratings
at Ta=25°C
Parameter
Maximum supply voltage
Output current
Junction temperature
Thermal resistance
Operating substrate temperature
Storage temperature
Available time for load shorted
Symbol
Conditions
Ratings
30
18
15
150
Per power transistor
1.6
110
–40 to +125
V
CC
= 13.2 V, R
L
= 2
Ω,
f = 50 Hz, P
O
= 25 W
2
Unit
V
V
A
°C
°C/W
°C
°C
s
V
CC
max (1) No signal (with circuit cut off) 30s
V
CC
max (2) With signal (f = 100 kHZ, Vin = 1 Vrms, t = 100 ms)
I
O
max
Tj
θj-c
Tc
Tstg
ts
Recommended Operating Conditions
at Ta=25°C
Parameter
Recommended supply voltage
Load resistance
Symbol
V
CC
R
L
Conditions
Ratings
13.2
2
Unit
V
Ω
Operating Characteristics
at Ta = 25°C, V
CC
= 13.2 V, R
L
= 2
Ω,
Rg = 600
Ω,
VG = 46 dB
Parameter
Quiescent current
Output power
Symbol
I
CCO
P
O
(1)
P
O
(2)
THD (1)
THD (2)
VG
f
L
, f
L
r
i
V
NO
∆VN
ATT
SVRR
Rg = 10 kΩ
THD = 10%, f = 1 kHz, R
L
= 1
Ω
THD = 10%, f = 1 kHz, R
L
= 2
Ω
P
O
= 10 W, f =1kHz
P
O
= 1 W, f = 20 to 20 kHz
P
O
= 1 W, f = 1 kHz
P
O
=1 W,
+0
dB
–3
20
43.8
46.0
20 to 30k
30
0.6
–200
0
∞
–47
1.2
+200
50
Conditions
min
typ
70
60
40
0.025
0.1
0.4
48.2
max
140
Unit
mA
W
W
%
%
dB
Hz
kΩ
mVrms
mV
dB
dB
Total harmonic distortion
Voltage gain
Frequency response
Input resistance
Output noise voltage
Output offset voltage
Muting suppression level
Ripple rejection
P
O
= 1 W, f = 1 kHz
Rg = 10 kΩ, BPF
Rg = 10 kΩ
V
M
= +5 V
f
R
= 100 Hz, Rg = 0
Ω,
V
R
= 0 dBm
Equivalent Circuit
No. 4376-2/8
STK4067
STK4067 Design Data
(1) The Protection Circuits
a) Overvoltage Protector
Since the STK4067 is designed for car stereo applications, V
CC
max for operating mode is set to 18 V.
Exceeding the V
CC
maximum level activates the overvoltage protector and the circuit switches to an off-state and
delivers no output. The overvoltage protection circuit is set for a functional range from 18 to 28 V; 100%
operation at 28 V. For this reason, you should be careful not to exceed the 18 V limit in quiescent mode and keep
in mind AC line regulations when setting using a transformer power supply for designs such as home stereo
systems. Exceeding 18 V activates the overvoltage protector and results in the generation of abnormal sounds.
b) Thermal Shutdown
The thermal shutdown protection circuit is designed to first detect abnormal temperature rises which occur during
abnormal operation (such as load shorts) and then prevent damage to the IC by limiting the input signal; thereby
preventing a further rise in the temperature. The thermal shutdown protector is set to activate at substrate
temperature of 135°C with a complete shutdown by switching to an off-state if temperatures rise to 175°C. Under
normal application, the IC is equipped with a heat sink and the temperature never reaches a level resulting in a
complete off-state switch and saturation occurs at a specific temperature. For example, when a short occurs with
an IC mounted 4.5°C/W heat sink, saturation is achieved at approximately 160°C. At this point, Tj exceeds its
maximum rating of 170°C. As previously mentioned, this circuit is designed to protect the IC from damage
sustained in a short period of time and you should note that the protection circuit will not protect the IC if
abnormal temperature rises occur over a long period of time.
(2) Precautions
a) Excessive Input
If a 1 V or greater (f = 1 kHz.rms) overinput is applied to the input pin, the DC balance of the input channel for
the input monolithic amplifier is disrupted and output is cut off. In addition, DC voltage is generated on the
output pins and causes damage to the speakers. Proper caution should be displayed in preventing input above this
voltage.
b) Parasitic Oscillation
The STK4067 performs phase compensation using 2.2Ω and 0.47µF between V
CC
and the bootstrap pins. Under
such conditions, the power supply line must be in a close proximity to the bootstrap pins for the inverting and
non-inverting amplifiers. If the power line is too long, parasitic oscillation is likely to occur at low temperatures.
If such a problem arises, add a 0.1µF rated condenser between the ground and the head of the power supply line
in order to lower the impedance.
c) Power Supply Voltage Inverse Application
The STK4067 is not equipped with a built-in power supply voltage inversion protection circuit. If the possibility
exists, one should be externally connected.
d) Power Off
Do not connect pin 1 of the V
CC
pin directly to the ground or else the IC will be damaged. When connecting pin
1, install a resistor rated for 100Ω or greater in series with pin 1, or you may place a diode between pin 10 and pin
1.
(3) Application Circuits
a) The under frequency band may be magnified, for applications using a booster amplifier or woofer driver
amplifier, the bootstrap condensers (C3 and C4) can be changed from 220µF to 470µF. Refer to P
O
-f graphs.
b) L1 = 3 µH and R3 = 4.7Ω are for anti-oscillation applications against capacity loads. We recommend the use of
this coil and resistor with the most compatible amplifier sets connected to general use speakers. This coil is not
necessary when the load capacity is low using a chosen speaker connected to a radio-cassette player or active
speaker.
No. 4376-3/8
STK4067
Example PCB
Sample Application Circuit
No. 4376-4/8
STK4067
Sample STK4067 Heat Sink Design
The radiator thermal resistance
θc-a
required for total substrate power dissipation Pd in the STK4067 is determined as:
Condition 1: IC substrate temperature Tc not to exceed 110°C.
Pd
x
θc-a+Ta
<110°C ······························· (1)
where Ta is set assured ambient temperature.
Condition 2: Power transistor junction temperature Tj not to exceed 150°C.
Pd
x
θc-a+Pd/N
x
θj-c+Ta<150°C·············(2)
where N is the number of power transistors and
θj-c
is the thermal resistance per power transistor chip.
However, power transistor power consumption is Pd equally divided by N units.
Expressions (1) and (2) can be rewritten based on
θc-a
to yield:
θc-a<(110–Ta)/Pd
······································(1)'
θc-a<(150–Ta)/Pd–θj-c/N··························(2)'
The required radiator thermal resistance will satisfy both of these expressions.
From expressions (1)' and (2)', the required radiator thermal resistance can be determined once the following
specifications are known:
•
•
•
Supply voltage
V
CC
Load resistance
R
L
Assured ambient temperature Ta
The total substrate power consumption when STK4067 V
CC
is ±13.2 V and R
L
is 2
Ω,
for a continuous sine wave
signal, is a maximum of 19.3W (Fig. 2).
The STK4067 has four power transistors, so the thermal resistance per transistor
θj-c
is 1.6°C / W. With an assured
ambient temperature Ta of 50°C, the required radiator thermal resistance
θc-a
would be:
From expression (1)'
θc-a
<(110–50)/19.3
<3.1
From expression (2)'
θc-a
<(150–50)/19.3–1.6/4
<4.78
To satisfy both, 3.1°C/W is the required radiator thermal resistance.
Figure 1 illustrates Pd - P
O
when the V
CC
of STK4067 is 13.2V and R
L
is functioning at 1Ω.
Pd max= 34.8W
From expression (1)'
θc-a
<(110–50)/34.8
<1.72
From expression (2)'
θc-a
<(150-50)/34.8–1.6/4
<2.47
To satisfy both, 1.72°C/W is the required radiator thermal resistance.
Similar to figure 3 when the STK4067’s V
CC
is 13.2 V and R
L
is 4Ω.
Pd max= 12W
From expression (1)'
θc-a
<(110–50)/12
<5
From expression (2)'
θc-a
<(150-50)/12–1.6/4
<7.93
To satisfy both, 5°C / W is the required radiator thermal resistance. This design example is based on a fixed voltage
supply, and will require verification within your specific set environment.
No. 4376-5/8
嵌入式系统
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