46 ICs
1-1-3 DC/DC Converter ICs
■Lineup
Part Number SI-8033S SI-8050S SI-8090S SI-8120S SI-8150S
VO(V) 3.3 5.0 9.0 12.0 15.0
IO(A) 3.0
■Absolute Maximum Ratings
Unit
V
W
W
°C
°C
V
°C/W
Ratings
43*
18(With infinite heatsink)
1.5(Without heatsink, stand-alone operation)
+125
–40 to +125
–1
5.5
Symbol
VIN
PD1
PD2
Tj
Tstg
VSW
θ
j-c
Parameter
DC Input V oltage
Power Dissipation
Junction Temperature
Storage Temperature
SW Terminal Applied Reverse Voltage
Thermal Resistance(junction to case)
■Features
•Compact full-mold package (equivalent to
TO220)
•Output current: 3.0A
•High efficiency: 79 to 91%
•Requires only 4 discrete components
•Internally-adjusted phase correction and output
voltage
•Built-in reference oscillator (60kHz)
•Built-in overcurrent and thermal protection
circuits
•Built-in soft start circuit (Output ON/OFF
available)
■Applications
•Power supplies for telecommunication equip-
ment
•Onboard local power supplies
*35V for SI-8033S
Full-Mold, Separate Excitation Step-down Switching Mode
SI-8000S Series
■Recommended Operating Conditions
Parameter
DC Input Voltage Range
Output Current Range
Operating Junction Temperature Range
Symbol
VIN
IO
Tjop
Unit
V
A
°C
Ratings
SI-8033S SI-8050S SI-8090S SI-8120S SI-8150S
5.5 to 28 7 to 40 12 to 40 15 to 40 18 to 40
0 to 3.0
–30 to +125
■Electrical Characteristics (Ta=25°C)
Unit
V
%
kHZ
mV
mV
mV/°C
A
V
µA
Parameter
Output Voltage
Efficiency
Oscillation Frequency
Line Regulation
Load Regulation
Temperature Coefficient of
Output Voltage
Overcurrent Protection
Starting Current
Soft
Start Pin*2
Symbol
VO
Conditions
η
Conditions
f
Conditions
∆VOLINE
Conditions
∆VOLOAD
Conditions
∆VO/∆Ta
IS1
Conditions
VSSL
ISSL
Conditions
SI-8000S*
1
SI-8000SS
Low-Level Voltage
Outflow Current at
Low Voltage
*1:“S” may be printed to the right of the marking (except SI-8090S, SI-8120S, SI-8150S).
*2:Pin 5 is a soft start pin. Soft start at power on can be performed with a capacitor connected to
this pin.
The output can also be turned ON/OFF with this pin.
The output is stopped by setting the voltage of this pin to VSSL or lower.
Soft-start pin voltage can be changed with an open-collector drive circuit of a transistor.
When using both the soft-start and ON/OFF functions together, the discharge current from C3
flows into the ON/OFF control transistor. Therefore, limit the current securely to protect the
transistor if C3 capacitance is large.
The ON/OFF pin is pulled up to the power supply in the IC, so applying the external voltage is
prohibited.
If this pin is not used, leave it open.
SI-8000S SI-8000S
ON/OFF5 ON/OFF5 ON/OFF
C3C3
5
VOUT. ON/OFF Soft start Soft start
+VOUT. ON/OFF
SI-8000S
Ratings
SI-8033S SI-8050S SI-8090S SI-8120S SI-8150S
min. typ. max. min. typ. max. min. typ. max. min. typ. max. min. typ. max.
3.17 3.30 3.43 4.80 5.00 5.20 8.55 9.00 9.45 11.50 12.00 12.50 14.25 15.00 15.75
3.234 3.30 3.366 4.90 5.00 5.10
V
IN
=15V, I
O
=1.0A V
IN
=20V, I
O
=1.0A V
IN
=21V, I
O
=1.0A V
IN
=24V, I
O
=1.0A V
IN
=25V, I
O
=1.0A
79 84 88 90 91
V
IN
=15V, I
O
=1.0A V
IN
=20V, I
O
=1.0A V
IN
=21V, I
O
=1.0A V
IN
=24V, I
O
=1.0A V
IN
=25V, I
O
=1.0A
60 60 60 60 60
V
IN
=15V, I
O
=1.0A V
IN
=20V, I
O
=1.0A V
IN
=21V, I
O
=1.0A V
IN
=24V, I
O
=1.0A V
IN
=25V, I
O
=1.0A
25 80 40 100 50 120 60 130 60 130
VIN=8 to 28V, IO=1.0A VIN=10 to 30V, IO=1.0A VIN=15 to 30V, IO=1.0A VIN=18 to 30V, IO=1.0A VIN=21 to 30V, IO=1.0A
10 30 10 40 10 40 10 40 10 40
V
IN
=15V, I
O
=0.5 to 1.5A V
IN
=20V, I
O
=0.5 to 1.5A V
IN
=21V, I
O
=0.5 to 1.5A V
IN
=24V, I
O
=0.5 to 1.5A V
IN
=25V, I
O
=0.5 to 1.5A
±0.5 ±0.5 ±1.0 ±1.0 ±1.0
3.1 3.1 3.1 3.1 3.1
V
IN
=15V V
IN
=20V V
IN
=21V V
IN
=24V V
IN
=25V
0.2 0.2 0.2 0.2 0.2
15 25 35 15 25 35 15 25 35 15 25 35 15 25 35
VSSL=0.2V
47
ICs
SI-8000S Series
■External Dimensions (TO220F-5) (Unit : mm)
■Block Diagram
■Typical Connection Diagram
■Ta-PD Characteristics
The efficiency depends on the input voltage and the output current.
Therefore, obtain the value from the efficiency graph and substi-
tute the percentage in the formula above.
VO:Output voltage
VIN :Input voltage
IO:Output current
ηx:Efficiency (%)
VF:Diode D1 forward voltage
0.5V(RK46)
Thermal design for D1 must be considered separately.
Pin Assignment
qVIN
wSWOUT
eGND
rVOS
tS.S
Plastic Mold Package Type
Flammability: UL94V -0
Product Mass: Approx. 2.3g
Forming No. 1101
10.0
±0.2
4.2
±0.2
0.95
±0.15
8.2
±0.7
2.6
±0.1
3.9
±0.7
(4.3)
(4.6)
(8.0) (17.9)
(2.0)
0.85
+0.2
–0.1
0.45
+0.2
–0.1
4.0
±0.2
7.9
±0.2
16.9
±0.3
0.5
12345
P1.7
±0.7
×4=6.8
±0.7
2.8
±0.2
3.2
±0.2
φ
2
Reg. OCP
OSC Reset
Amp.
TSD
V
REF
Comp.
Drive
1
4V
OS
V
IN
SW
OUT
GNDS.S.
53
VIN
C1D1
L1
VIN VO
GNDS.S
GND GND
SI-8000S
SWOUT
VOS
12
3
+C2
+
5
4
C1,2 :1000
µ
F
L1:150
µ
H
D1:RK46(Sanken)
15
20
10
5
0
–25 0 25 50
Operating Ambient Temperature Ta (°C)
Power Dissipation PD (W)
75 125100
200×200×2mm
(2.3°C/W)
100×100×2mm
(5.2°C/W)
75×75×2mm
(7.6°C/W)
Infinite heatsink
Without heatsink
With Silicone Grease
Heatsink: Aluminum
PD=VO•IO 100 –1 –VF•IO 1– VO
ηχ
VIN
