STR7000/7100
Series
Switching Type
Features
q
High output/efficiency and stable operation
q
Wide DC input voltage range
q
Provided with adjustable dropping type current pro-
tection circuit
q
Foldback type overcurrent protection may be easily
set externally
q
Built-in reference oscillator (35 kHz)
q
Variable output voltage
q
Output ON/OFF by external signal
q
Use of SANKEN's semiconductor ensures high reli-
ability
Chopper • Separate Excitation Type
Applications
q
For computer terminals, numeric control equipment
and office equipment
External View
s
Lineup
Control Hybrid IC (SI-8020 series)
SI-8020 (V
OUT
=5V)
SI-8021 (V
OUT
=12V)
SI-8022 (V
OUT
=15V)
SI-8023 (V
OUT
=24V)
Main Switcher Hybrid IC (STR7000, 7100 series)
I
OUT
=6A
STR7001
STR7002
STR7002
STR7003
I
OUT
=12A
STR7101
STR7102
STR7102
STR7103
s
Absolute Maximum Ratings
Main Switcher Hybrid IC: STR7000, STR7100 Series (Ta=25°C)
Parameter
Power Transistor Breakdown Voltage
Drive Transistor Breakdown Voltage
Diode Breakdown Voltage
Collector Current
Power Dissipation
Power Transistor Thermal Resistance
Power Transistor Junction Temperature
Operating Temperature
Storage Temperature
Symbol
STR7000 Series
V
4-1
V
4-5
V
1-2
I
C
P
D
R
th(j-c)
T
j
T
op
T
stg
6 (peak 7.5A)
100 (T
C
=25°C)
60
60
60
12 (peak 15A)
125 (T
C
=25°C)
Ratings
STR7100 Series
V
V
V
A
W
°C/W
°C
°C
°C
Unit
4.3 (Without heat Sink)
1.25
+150
–30 to +125 (T
C
)
–30 to +125
1.0
Control Hybrid IC: SI-8020 Series (Ta=25°C)
Parameter
DC Input Voltage
Power Dissipation
Operating Temperature
Storage Temperature
Symbol
V
IN
P
D
T
op
T
stg
Ratings
55
1
–20 to +85
–20 to +100
Unit
V
W
°C
°C
18
s
Electrical Characteristics (Ta=25°C): 6A Type
Ratings
Parameter
Symbol STR7001, SI-8020
min
DC Input Voltage Range
Output Voltage
V
IN
V
O
Condition
Line Regulation
∆V
OLINE
∆V
OLOAD
Condition
Efficiency
11
5.0
5.1
typ
max
40
5.2
STR7002, SI-8021
min
18
11.8
12.0
typ
max
50
12.2
STR7002, SI-8022
min
21
14.8
15.0
typ
max
50
15.2
STR7003, SI-8023
min
30
23.7
24.0
typ
max
50
24.3
V
V
Unit
V
IN
=20V, I
O
=3A
80
V
IN
=27V, I
O
=3A
120
V
IN
=22 to 32V, I
O
=3A
40
V
IN
=27V, I
O
=1 to 5A
84
V
IN
=27V, I
O
=3A
45
V
IN
=30V, I
O
=3A
150
V
IN
=25 to 35V, I
O
=3A
40
V
IN
=30V, I
O
=1 to 5A
86
V
IN
=30V, I
O
=3A
45
V
IN
=40V, I
O
=3A
200
V
IN
=35 to 45V, I
O
=3A
50
V
IN
=40V, I
O
=1 to 5A
90
V
IN
=40V, I
O
=3A
45
dB
7.5
7.5
A
A
%
mV
mV
Condition V
IN
=15 to 25V, I
O
=3A
Load Regulation
30
V
IN
=20V, I
O
=1 to 5A
72
V
IN
=20V, I
O
=3A
45
η
Condition
R
REJ
Condition
Ripple Rejection
Overcurrent Protection
Starting Current
Limited Current at
overcurrent protection
operation
f = 100 to 120 Hz
6.0
6.0
7.5
7.5
6.0
6.0
7.5
7.5
6.0
6.0
7.5
7.5
6.0
6.0
I
S1
I
S2
Condition
R
S
= 0.02Ω
s
Electrical Characteristics (Ta=25°C): 12A Type
Ratings
Parameter
Symbol STR7101, SI-8020
min
DC Input Voltage Range
Output Voltage
V
IN
V
O
Condition
∆V
OLINE
∆V
OLOAD
Condition
11
5.0
5.1
typ
max
40
5.2
STR7102, SI-8021
min
18
11.8
12.0
typ
max
50
12.2
STR7102, SI-8022
min
21
14.8
15.0
typ
max
50
15.2
STR7103, SI-8023
min
30
23.7
24.0
typ
max
50
24.3
V
V
Unit
V
IN
=20V, I
O
=6A
80
V
IN
=27V, I
O
=6A
120
V
IN
=22 to 32V, I
O
=6A
40
V
IN
=27V, I
O
=3 to 9A
82
V
IN
=27V, I
O
=6A
45
V
IN
=30V, I
O
=6A
150
V
IN
=25 to 35V, I
O
=6A
40
V
IN
=30V, I
O
=3 to 9A
84
V
IN
=30V, I
O
=6A
45
V
IN
=40V, I
O
=6A
200
V
IN
=35 to 45V, I
O
=6A
50
V
IN
=40V, I
O
=3 to 9A
87
V
IN
=40V, I
O
=6A
45
Line Regulation
Condition V
IN
=15 to 25V, I
O
=6A
30
V
IN
=20V, I
O
=3 to 9A
70
V
IN
=20V, I
O
=6A
45
mV
Load Regulation
mV
Efficiency
η
Condition
R
REJ
%
Ripple Rejection
Overcurrent Protection
Starting Current
Limited Current at
overcurrent protection
operation
Condition
I
S1
I
S2
Condition
12
12
15
15
12
12
f = 100 to 120 Hz
15
15
12
12
15
15
12
12
15
15
dB
A
A
R
S
= 0.01Ω
19
STR7000/7100
Series
Switching Type
Chopper • Separate Excitation Type
s
Outline Drawing/Terminal Connections (unit:mm)
STR7000/7100 Series
36.0
±0.3
24.4
±0.2
SI-8020 Series
30max.
6max.
6.0
max.
2.0
±0.2
φ
3.2
±0.1
3 0
°
12.0
±0.3
21.2
±0.3
Terminal 1
marking
Lot number
3.0
0.6
–0.1
+0.2
4.7
max.
20.0
min.
2.0
+0.2
1.0
–0.1
q
w
e
r
t
0.5
±0.05
2.54
±0.1
1
2
3
4
5
6
7
8
9 10
25max.
0.27
±0.05
Lot Number
Type
Type
3.5
5.45×4
5.45
7max.
Terminal Connections
Plastic Mold Package Type
Flammability: UL94V-0
Weight: Approx. 14.5 g
q
Switching Output
(backside of case)
w
Fly Wheel (ground)
e
Drive
r
Input
t
Ground
Plastic Mold Package Type
(powder coating)
Weight: Approx. 3.4 g
s
Block Diagram
STR7000/7100 Series
SI-8020 Series
9
OSC.OUT SHUT DOWN
V
IN
10
V
IN
4
SW.OUT
1
VOLTAGE
REFERENCE
and
REGULATOR
DEAD TIME
CONTROLLED
RAMP
GENERATOR
PWM COMP
4.5
±1.0
7 V
REF
+
–
5 DRIVE
DRIVE
3
1 GND
I
O
AMP
V
O
AMP
+
–
5
GND
2
F.WHEEL
+
–
2 V
O ADJ
4
CURR.SENSE
8
COMPENSATION. A
6
COMPENSATION. B
3 V
O
.SENSE
20
s
Standard External Circuit
5V ... 200µH
12V ...
250µH
15V
24V ... 300µH
V
IN
4
SW
V
IN
STR7000
STR7100
SERIES DRIVE 3
C
5
330P
5
DRIVE
V
IN
C.A SI-8020
SERIES
C.B
V
REF
GND
1
C.S
V
O.S
1
L
V
OUT
DC Input
*
F/W
2
GND
5
DC Output
3
2
9
4
+
V
O
. ADJ
OSC. OUT
SHUT DOWN
C
4
1500µF
×
2
10
C
1
2200µF
+
C
2
330p
8
6
7
C
3
10µF
*
C
5
STR7100 Series only
R
S
6A ... 0.02Ω
12A ... 0.01Ω
GND
s
Typical Operating Characteristics
Ta-PD Characteristics
(STR7000 Series)
40
200
×
300
×
2
35
200
×
200
×
2
30
100
×
200
×
2
Ta-PD Characteristics
(STR7100 Series)
40
200
×
300
×
2
Without Mica
With Silicone Grease
Heatsink : Aluminum
Unit : mm
Without Mica
With Silicone Grease
Heatsink : Aluminum
Unit : mm
35
200
×
200
×
2
30
Power Dissipation P
D
(W)
Power Dissipation P
D
(W)
25
100
×
200
×
2
25
20
100
×
100
×
2
15
75
×
75
×
2
10
20
100
×
100
×
2
15
75
×
75
×
2
10
5
Without heatsink
5
Without heatsink
0
-20
0
25
50
75
100
125
0
-20
0
25
50
75
100
125
Ambient temperature Ta (°C)
Ambient temperature Ta (°C)
21
STR7000/7100
Series
Switching Type
Chopper • Separate Excitation Type
Caution
1. Selecting the external parts
1) Inductance L
To maintain the stable operation of inductance L,
dangerous conditions including operation under
saturated or high temperature conditions due to
self generation of heat must be avoided.
Take the following into consideration when select-
ing inductance L:
a) It must be suited for switching regulators.
Do not use inductors for noise filters, as they
generate excess heat.
b) It must have an appropriate inductance value.
The inductance values shown in the Standard
External Circuit diagram are based on each of
zero current assumption and are suitable for
each of the output voltages.
The appropriate inductance may also be ob-
tained as follows:
I
o(min)
= critical current value; f = 35 kHz
2) Capacitor C
1
Capacitor C
1
supplies the steep current gener-
ated during switching to the load and compen-
sates for the voltage drop in the input.
Therefore, it is important that capacitor C
1
is
placed adjacent to the IC as described below.
Keep the following in mind when selecting C
1
.
a) It must satisfy the breakdown voltage.
b) It must satisfy the allowable ripple current.
Use of the capacitor over the derating value
shortens its life (by bursting, decrease in capaci-
tance, increase of ESR), and may also cause
abnormal oscillation of the IC. Therefore, it is
important to select C
1
with sufficient margin.
3) Capacitor C
4
Capacitor C
4
is a smoothing capacitor for the
switching output.
The pulsed part
∆I
L
of the inductance current is
charged/discharged to/from C
4
.
Therefore, it is important to keep in mind the
breakdown voltage and the allowable ripple cur-
rent when selecting C
1
.
4) Current Detection Resistor R
S
Take note of the power dissipation as a large
current flows through Rs. Moreover, take note that
the overcurrent protection may not work if a com-
mon input and output ground terminal is used.
5) Capacitor C
2
Capacitor C
2
is a phase compensation capacitor
for the voltage error amplifier.
6) Capacitor C
3
Capacitor C
3
is for stabilization of the reference
voltage. Oscillation may occur if there is no C
3
.
7) Capacitor C
5
Capacitor C
5
is for delaying the waveform of the
DRIVE output.
(V
IN
– V
O
) V
O
• • • • •
(1)
2 • I
O
(min.) • V
IN
• f
c) The rated current must be satisfied.
The inductance decreases dramatically as the
rated current is exceeded, and ultimately satu-
rates. In such a case high frequency imped-
ance decreases, resulting in excess current.
d) It must have excellent DC current superposition
characteristics.
Inductance has the tendency to decrease by
an increase in current. When selecting the
inductance, keep in mind that it is usable up to
50% decrease of the rated current.
L=
100%
50%
I
O
max I
22
