1-1-3 DC/DC Converter ICs
SI-8000TFE Series Full-Mold, Separate Excitation Step-down Switching Mode
■Features
■Lineup
• Compact full-mold package (equivalent to
TO220)
Part Number
SI-8008TFE
VO (V)
Variable (0.8 to 24)
• Output current: 1.5 A
SI-8050TFE
5
IO (A)
1.5
• High efficiency: 81% typ. (at Vo = 5 V)
• Requires only 4 discrete components
• Built-in reference oscillator (300 kHz)
■Absolute Maximum Ratings
• Built-in dropping-type-overcurrent and thermal
protection circuits
DC Input Voltage
• Output ON/OFF available (circuit current at
output OFF: 200µA typ.)
Power Dissipation
Parameter
Symbol
Ratings
Unit
VIN
43
V
PD1-1
17.8 (with infinite heatsink)
PD1-2
14.2 (with infinite heatsink)
PD2-1
2.15 (without heat sink, standalone operation)
PD2-2
1.72 (without heatsink, standalone operation)
Tj
–30 to +150
Storage Temperature
Tstg
–40 to +150
°C
Thermal Resistance (Junction to Case)
θ j-c
7
°C/W
Thermal Resistance (Junction to Ambient Air)
θ j-a
58
°C/W
• Soft start available by ON/OFF pin
Junction Temperature*
■Applications
• Onboard local power supplies
• AV equipment
• OA equipment
Conditions
Limited by thermal protection, Tjmax=150°C
Tjmax=125°C
W
Limited by thermal protection, Tjmax=150°C
Tjmax=125°C
°C
*: This product has built-in thermal protection circuits that may operate when the junction temperature rises above 130°C.
The recommended design for the junction temperature during operation is below 125°C.
■Recommended Operating Conditions
Ratings
Parameter
Symbol
Input Voltage Range
VIN
Output Voltage Range
VO
Output Current Range
SI-8008TFE
SI-8050TFE
Vo+3*1 to 40
0.8 to 24
8 to 40
5.0
Tjop
Operating Temperature Range
Top
(Ta=25°C)
V
V
A
0 to 1.5
–20 to +125
–20 to +85
IO
Operating Junction Temperature Range
Unit
°C
°C
*1: The minimum value of an input voltage range is the higher of 4.5 V or VO + 3 V.
■Electrical Characteristics
(Ta=25°C)
Ratings
Parameter
Symbol
SI-8008TFE
typ.
min.
Output Voltage
Reference Voltage
Temperature Coefficient of Output Voltage
Temperature Coefficient of Reference Voltage
Vo
VADJ
0.784
Conditions
∆Vo/∆T
∆VREF/∆T
Conditions
η
Efficiency
Conditions
Oscillation Frequency
Conditions
Low Level Voltage
ON/OFF Pin*
Outflow Current at
Low Voltage
Conditions
10
VSSL=0V
Conditions
6
VIN=15V, Io=0A
Conditions
200
VIN=15V, VSS=0V
Iq(OFF)
mV/°C
80
40
400
0.5
40
200
VIN=15V, VSS=0V
SI-8000TFE
5 SS
mV
mV
A
10
VSSL=0V
V
µA
mA
400
SI-8000TFE
5 SS
µA
SI-8000TFE
5 SS
C3
VO.ON/OFF
ICs
40
6
VIN=15V, Io=0A
*: Pin 5 is the SS 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. SS-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 SS pin is pulled up to the
power supply in the IC, so applying the external voltage is prohibited. If the pin is not used,
leave it open.
40
80
VIN=15V
0.5
40
%
kHz
1.6
VIN=15V
Iq
V
VIN=15V, Io=0.1A
±0.5
1.6
Conditions
VSSL
ISSL
Quiescent Circuit Current
0.816
300
VIN=15V, Io=0.5A
60
VIN=10 to 30V, Io=0.5A
10
VIN=15V, Io=0.2 to 1.5A
∆VOLOAD
IS
max.
5.10
300
VIN=15V, Io=0.5A
60
VIN=10 to 30V, Io=0.5A
10
VIN=15V, Io=0.2 to 1.5A
fo
Conditions
Overcurrent Protection
Starting Current
Unit
SI-8050TFE
typ.
5.00
min.
4.90
VIN=15V, Io=0.1A, Tc=0 to 100°C
81
VIN=15V, Io=0.5A
∆VOLINE
Load Regulation
max.
±0.1
VIN=15V, Io=0.1A, Tc=0 to 100°C
81
VIN=15V, Io=0.5A
Conditions
Line Regulation
0.800
VIN=15V, Io=0.1A
Ratings
Soft start
C3
Soft start
+VO.ON/OFF
SI-8000TFE Series
■External Dimensions (TO220F-5)
(Unit : mm)
±0.2
4.2
±0.2
2.8
φ 3.2±0.2
0.5
±0.2
(2.0)
2.6±0.1
Pin Assignment
q IN
w SW
e GND
r ADJ
t SS
(17.9)
16.9±0.3
4.0±0.2
7.9±0.2
10.0
(4.6)
+0.2
4.6±0.6
0.95±0.15
0.85 –0.1
Plastic Mold Package Type
Flammability: UL94V-0
Product Mass: Approx. 2.3g
+0.2
P1.7±0.7×4=6.8±0.7
0.45 –0.1
3.9±0.7
(4.3)
8.2±0.7
1 2 3 4 5
■Block Diagram
■Typical Connection Diagram
L1
47µH
SW
IN
5 SS
Latch &
Drive
Reset
SW
IN
SI-8000TFE
C1
220µF
+
SS
5
GND
3
2
VOUT
R1
ADJ 4
+
R2
Di
C2
470µF
IADJ
C3
OSC
+
–
ON/OFF
Soft Start
2
Overcurrent
Protection
PReg.
Thermal ADJ
Protection
4
Comp.
Error Amp.
+
+
–
1
1
VIN
SI-8008TFE
Reference
Voltage
GND
3
GND
GND
C1 : 220µF
C2 : 470µF
C3 :1µF (Only when using soft-start function)
L1 : 47µH
Di : RK16 (Sanken)
ICs
41