STK4048

 

XI

 

SANYO Electric Co., Ltd. Semiconductor Business Headquarters

 

TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN

 

70397HA (ID) / 9148TA No. 2909—1/8

Ordering number: 2909A

 

Thick Film Hybrid IC

 

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).

• Possible to design electronic supplementary circuits

(pop noise muting at the time of power ON/OFF, load
short protector, thermal shutdown)

 

Package Dimensions

 

unit: mm

 

4051A

 

[STK4048

 

XI

 

]

 

Specifications

 

Maximum Ratings 

 

at Ta = 25

 

°

 

C

 

Recommended Operating Conditions 

 

at Ta = 25

 

°

 

C

 

Parameter

Symbol

Conditions

Ratings

Unit

 

Maximum supply voltage

V

 

CC

 

 max

 

±

 

87

V

Thermal resistance

 

Θ

 

j-c

Per power Transistor

1.2

 

°

 

C/W

Junction temperature

Tj

150

 

°

 

C

Operating substrate temperature

T

 

C

 

125

 

°

 

C

Storage temperature

Tstg

 

-

 

30 to +125

 

°

 

C

 

Parameter

Symbol

Conditions

Ratings

Unit

 

Recommended supply voltage

V

 

CC

 

±

 

60

V

Load resistance

R

 

L

 

8

 

Ω¦

 

STK4048

 

XI

 

No. 2909—2/8

 

Operating Characteristics 

 

at Ta = 25

 

°

 

C, V

 

CC

 

 = 

 

±

 

60V, R

 

L

 

 = 8

 

Ω¦

 

, VG = 40dB, Rg = 600

 

Ω¦

 

, 100kHz LPF ON, 

R

 

L 

 

: noninductive load

 

Parameter

Symbol

Conditions

min

typ

max

Unit

 

Quiescent current

Icco

V

 

CC

 

 = 

 

±

 

72V

15

120

mA

Output power

Po

THD = 0.008%, 
f = 20Hz to 20kHz

150

W

Total harmonic distortion

THD

Po = 1.0W, f = 1kHz

0.008

%

Frequency response

f

 

L

 

, f

 

H

 

Po = 1.0W, 

dB

20 to 50k

Hz

Input impedance

r

 

i

 

Po = 1.0W, f = 1kHz

55

k

 

Ω¦

 

Output noise voltage

V

 

NO

 

*

V

 

CC

 

 = 

 

±

 

72V, Rg = 10k

 

Ω¦

 

1.2

mVrms

Neutral voltage

V

 

N

 

V

 

CC

 

 = 

 

±

 

72V

-70

0

+70

mV

+0
-3

 

Specified Transformer Power Supply

(Equivalent to MG250)

 

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.

 

Equivalent Circuit

 

STK4048

 

XI

 

No. 2909—3/8

 

Sample Application Circuit:

 

 150W min Single-Channel AF Power Amplifier

 

Sample Printed Circuit Pattern for Application Circuit 

 

(Cu-foiled side)

 

STK4048

 

XI

 

No. 2909—4/8

 

Input voltage, Vi - mV

Frequency, f - Hz

Operating substrate temperature, Tc - 

 

°

 

C

Output po

wer

, Po - 

W

Output po

wer

, Po - 

W

Quiescent current, Icco - mA

Neutral v

oltage, 

V

N

 - mV

 

Output power, Po - W

Frequency, f - Hz

Supply voltage, V

 

CC

 

 - V

T

otal harmonic distortion, 

THD - %

V

oltage g

ain, 

V

G

 - dB

Quiescent current, Icco - mA

Neutral v

oltage, 

V

N

 - mV

 

STK4048

 

XI

 

No. 2909—5/8

 

Supply voltage, V

 

CC

 

 - V

Frequency, f - Hz

Output po

wer

, Po - 

W

V

oltage g

ain, 

V

G

 - dB

 

Output power, Po - W

IC Po

wer dissipation, Pd - 

W

 

Description of External Parts

 

STK4048

 

XI

 

No. 2909—6/8

 

R1, C1

Input filter circuit
• Used to reduce noise at high frequencies.

C2

Input coupling capacitor
• 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.

R2

Input bias resistor
• Used to bias the input pin to zero.
• Affects V

 

N

 

 stability. (See NF circuit.)

• Because of differential input, this resistor fixes the input resistance practically.

R4, R5

C3 (C2)

NFB circuit (AC NF circuit). It is desirable that the error of the resistor value is 1% or less.

C3

: Capacitor for AC NF

R4, R5

: Used to set VG

• 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

 

N

 

 balance. If the resistor value is increased 

more than the existing value, it may be hard to ensure V

 

N

 

 balance and the temperature characteristic of V

 

N

 

 may be also deteriorated.

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.)

C6, C9

Used for oscillation blocking and phase compensation
(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

C11, C12

Used for oscillation blocking
• 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

VG

20

log

R

5

R

4

------

40dBisrecommended

Ë™

(

)

•‹…

=

f

L

 

2

 

Ï€

 

R

 

4

 

C

 

3

 

•‹…

•‹…

 

----------------------------

 

Hz

 ( )

 

=

 

STK4048

 

XI

 

No. 2909—7/8

 

Thermal Design

 

The IC power dissipation of the STK4048XI at the IC-
operated 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.

 

Figure 1. STK4048XI Pd - Po (R

 

L

 

 = 8

 

Ω¦

 

)

 

Output power, Po - W

IC Po

wer dissipation, Pd - 

W

 

Condition 1: Tc = Pd 

 

× Θ

 

c-a + Ta 

 

≤

 

 125

 

°

 

C .............................................. (1)

where

Ta : Specified ambient temperature
Tc : Operating substrate temperature

Condition 2: T

 

j 

 

= Pd 

 

× (Θ

 

c-a) + Pd/4 

 

× (Θ

 

j-c) + Ta 

 

≤

 

 150

 

°

 

C .................... (2)

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 ine-

qualities (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 speci-
fied for a stereo amplifier is 50

 

°

 

C.

Assuming V

 

CC

 

 = 

±

60V, R

L

 = 8

Ω¦

,

R

L

 = 8

Ω¦

 : Pd = 65W at 1/10 Po max.

The thermal resistance of a heat sink is
obtained from Figure 2.
R

L

 = 8

Ω¦

 : 

Θ

c-a1 = 1.15

°

C/W

Tj when a heat sink is used is obtained from
(3).
R

L

 = 8

Ω¦

 : Tj = 144.3

°

C

Figure 2. STK4048XI 

Θ

c-a - Pd

IC Power dissipation, Pd - W

Thermal resistance of heat sink, 

Θ

c-a - 

°

C/W

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.

STK4048

XI

No. 2909—8/8

•– 

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-prevention equipment and the like, 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:

•ž€

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:

•ž�

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 example 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.