Ordering number: 2909A
±
θ
°
°
°
−
° C
±
8
Thick Film Hybrid IC
STK4048 XI
AF Power Amplifier (Split Power Supply)
(150W min, THD = 0.008%)
Features
• The use of a current mirror circuit, cascode circuit, pure
complementary circuit provides low distortion (THD=
0.008%/100kHz LPF ON).
Package Dimensions
unit: mm
4051A
[STK4048 XI ]
• Possible to design electronic supplementary circuits
(pop noise muting at the time of power ON/OFF, load
short protector, thermal shutdown)
Specifications
Maximum Ratings
Parameter Symbol Conditions Ratings Unit
Maximum supply voltage V
Thermal resistance
Junction temperature Tj 150
Operating substrate temperature T
Storage temperature Tstg
at Ta = 25 ° C
max
CC
j-c Per power Transistor 1.2
C
30 to +125
87 V
125
C/W
C
C
Recommended Operating Conditions
Parameter Symbol Conditions Ratings Unit
Recommended supply voltage V
Load resistance R
CC
L
SANYO Electric Co., Ltd. Semiconductor Business Headquarters
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN
at Ta = 25 ° C
60 V
Ω
70397HA (ID) / 9148TA No. 2909—1/8
STK4048 XI
Operating Characteristics
Parameter Symbol Conditions min typ max Unit
Quiescent current Icco V
Output power Po
Total harmonic distortion THD Po = 1.0W, f = 1kHz 0.008 %
Frequency response f
Input impedance r
Output noise voltage V
Neutral voltage V
Notes. For power supply at the time of test, use a constant-voltage power
supply unless otherwise specified.
*The output noise voltage is represented by the peak value on rms
scale (VTVM) of average value indicating type. The noise voltage
waveform includes no flicker noise. For measurement of the output
noise voltage, use the specified transformer power supply shown
right.
at Ta = 25 ° C, V
R
: noninductive load
L
, f
L
H
i
*V
NO
N
= ± 60V, R
CC
= ± 72V 15 120 mA
CC
THD = 0.008%,
f = 20Hz to 20kHz
Po = 1.0W, dB 20 to 50k Hz
Po = 1.0W, f = 1kHz 55 k Ω
V
+0
–3
= ± 72V, Rg = 10k Ω
CC
= ± 72V –70 0 +70 mV
CC
= 8 Ω , VG = 40dB, Rg = 600 Ω , 100kHz LPF ON,
L
150 W
1.2 mVrms
Specified Transformer Power Supply
(Equivalent to MG250)
Equivalent Circuit
No. 2909—2/8
STK4048 XI
Sample Application Circuit:
150W min Single-Channel AF Power Amplifier
Sample Printed Circuit Pattern for Application Circuit
(Cu-foiled side)
No. 2909—3/8
Output power, Po - WOutput power, Po - WQuiescent current, Icco - mA
Neutral voltage, V
N
- mV
STK4048 XI
Total harmonic distortion, THD - %Voltage gain, VG - dBQuiescent current, Icco - mA
Input voltage, Vi - mV
Frequency, f - Hz
Output power, Po - W
Frequency, f - Hz
Operating substrate temperature, Tc - ° C
- mV
N
Neutral voltage, V
Supply voltage, V
CC
- V
No. 2909—4/8
STK4048 XI
Output power, Po - WVoltage gain, VG - dB
Supply voltage, V
Frequency, f - Hz
CC
- V
Description of External Parts
IC Power dissipation, Pd - W
Output power, Po - W
No. 2909—5/8
STK4048 XI
1
R1, C1
Input filter circuit
• Used to reduce noise at high frequencies.
Input coupling capacitor
C2
• Used to block DC current. When the reactance of the capacitor increases at low frequencies, the dependence of 1/f noise on signal source
resistance causes the output noise to worsen. It is better to decrease the reactance.
Input bias resistor
R2
• Used to bias the input pin to zero.
• Affects V
• Because of differential input, this resistor fixes the input resistance practically.
stability. (See NF circuit.)
N
NFB circuit (AC NF circuit). It is desirable that the error of the resistor value is 1% or less.
R4, R5
C3 (C2)
• VG setting obtained by using R4, R5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
• Low cutoff frequency setting obtained by using, R4, C3. . . . . . . . . . . . . . . . . . . . . . .
• Change of VG setting
• It is desirable to change R4. In this case, the low cutoff frequency setting needs to be rechecked.
• When VG setting is changed by changing R5, R5 must be made equal to R2 to ensure V
more than the existing value, it may be hard to ensure V
R3 First-stage constant-current bias resistor
R6, C7 Used for oscillation blocking and phase compensation
R7, C4
Used for oscillation blocking and phase compensation
(C4 : A polyester film capacitor is recommended.)
Used for oscillation blocking and phase compensation
C6, C9
(Must be connected near the pin)
C6 : Power amp on (+) side C9 : Power amp on (–) side
C4
Used for oscillation blocking and phase compensation
(Used for oscillation blocking before clip)
C5 Used for oscillation blocking and distortion improvement
C8, C10 Ripple filter circuit on (+) side
R9, C13 Ripple filter circuit on (–) side
Used for oscillation blocking
C11, C12
• Used to decrease the power supply impedance to operate the IC stably. Must be connected near the IC pin. It is desirable to use an
electrolytic capacitor.
L1, R14 Used for oscillation blocking
R10, R11
R12, R13
Output limiting resistors
C3 : Capacitor for AC NF
R4, R5 : Used to set VG
VG 20log
=
f
L
balance and the temperature characteristic of V
N
N
⋅=
2 π
----------------------------
balance. If the resistor value is increased
R
⋅⋅
4
R
5
------
()
40dBisrecommended
R
4
Hz
()
C
3
may be also deteriorated.
N
˙
No. 2909—6/8
STK4048 XI
Thermal Design
The IC power dissipation of the STK4048XI at the ICoperated mode is 100W max. at load resistance 8 Ω for
continuous sine wave as shown in Figure 1.
In an actual application where a music signal is used, it is
impractical to estimate the power dissipation based on the
continuous signal as shown right, because too large a heat
sink must be used. It is reasonable to estimate the power
dissipation as 1/10 Po max. (EIAJ).
That is, Pd = 65W at 8 Ω
Thermal resistance θ c-a of a heat sink for this IC power
dissipation (Pd) is fixed under conditions 1 and 2 shown
below.
Condition 1: Tc = Pd × θ c-a + Ta ≤ 125 ° C .............................................. (1)
where Ta : Specified ambient temperature
Tc : Operating substrate temperature
IC Power dissipation, Pd - W
Output power, Po - W
Figure 1. STK4048XI Pd – Po (R
= 8 Ω )
L
Condition 2: T
= Pd × (θ c-a) + Pd/4 × (θ j-c) + Ta ≤ 150 ° C....................(2)
j
where Tj : Junction temperature of power transistor
Assuming that the power dissipation is shared equally among the four power transistors, thermal resistance θ j-c is
1.2 ° C/W and
Pd × (θ c-a + 1.2/4) + Ta ≤ 150 ° C........................................(3)
Thermal resistance θ c-a of a heat sink must satisfy inequalities (1) and (3).
Figure 2 shows the relation between Pd and θ c-a given
from (1) and (3) with Ta as a parameter.
[Example] The thermal resistance of a heat sink is
obtained when the ambient temperature specified for a stereo amplifier is 50 ° C.
Assuming V
= ±60V, RL = 8Ω,
CC
RL = 8Ω : Pd = 65W at 1/10 Po max.
The thermal resistance of a heat sink is
obtained from Figure 2.
RL = 8Ω : θc-a1 = 1.15°C/W
Tj when a heat sink is used is obtained from
(3).
RL = 8Ω : Tj = 144.3°C
Thermal resistance of heat sink, θc-a - °C/W
IC Power dissipation, Pd - W
Figure 2. STK4048XI θc-a – Pd
This design is based on the use of a constant-voltage regulated power supply. Pd differs when a transformer power supply
is used. Redesign must be made based on Pd that suits the regulation of each transformer.
No. 2909—7/8
STK4048XI
■
No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment, nuclear
power control systems, vehicles, disaster/crime-pre v ention equipment and the lik e, the failure of which may directly or indirectly cause injury,
death or property loss.
■
Anyone purchasing any products described or contained herein for an above-mentioned use shall:
➀
Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors and all their
officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and expenses associated
with such use:
➁
Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on SANYO ELECTRIC CO.,
LTD., its affiliates, subsidiaries and distributors or any of their officers and employees, jointly or severally.
■
Information (including circuit diagrams and circuit parameters) herein is for e xample only; it is not guaranteed for volume production. SANYO
believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of
intellectual property rights or other rights of third parties.
This catalog provides information as of July, 1997. Specifications and information herein are subject to change without notice.
No. 2909—8/8
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