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
Part Number
SI-8008TFE
SI-8050TFE
5
TO220)
VO (V)
Variable (0.8 to 24)
• Output current: 1.5 A
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
Parameter
Symbol
Ratings
43
Unit
V
Conditions
• Built-in dropping-type-overcurrent and thermal
protection circuits
DC Input Voltage
VIN
PD1-1
PD1-2
PD2-1
PD2-2
Tj
17.8 (with infinite heatsink)
14.2 (with infinite heatsink)
Limited by thermal protection, Tjmax=150°C
jmax=125°C
Limited by thermal protection, Tjmax=150°C
jmax=125°C
• Output ON/OFF available (circuit current at
T
Power Dissipation
W
output OFF: 200µA typ.)
2.15 (without heat sink, standalone operation)
• Soft start available by ON/OFF pin
1.72 (without heatsink, standalone operation)
T
Junction Temperature*
–30 to +150
°C
°C
Storage Temperature
Tstg
–40 to +150
Thermal Resistance (Junction to Case)
Thermal Resistance (Junction to Ambient Air)
θj-c
7
°C/W
°C/W
■Applications
θj-a
58
• Onboard local power supplies
*: 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.
• AV equipment
• OA equipment
■Recommended Operating Conditions
Ratings
Parameter
Symbol
Unit
SI-8008TFE
Vo+3*1 to 40
0.8 to 24
SI-8050TFE
8 to 40
5.0
(Ta=25°C)
Input Voltage Range
VIN
VO
IO
V
V
Output Voltage Range
Output Current Range
0 to 1.5
A
Operating Junction Temperature Range
Operating Temperature Range
Tjop
Top
–20 to +125
–20 to +85
°C
°C
*1: The minimum value of an input voltage range is the higher of 4.5 V or V + 3 V.
O
■Electrical Characteristics
(Ta=25°C)
Ratings
Ratings
Parameter
Symbol
Unit
SI-8008TFE
typ.
SI-8050TFE
typ.
min.
max.
min.
4.90
max.
5.10
5.00
Vo
(VADJ
Output Voltage
(Reference Voltage)
)
0.784
0.800
0.816
V
Conditions
V
IN=15V, I
o
=0.1A
V
IN=15V, I
o=0.1A
0.5
∆Vo/∆T
(∆VREF/∆T)
Conditions
Temperature Coefficient of Output Voltage
0.1
=0.1A, T
81
mV/°C
(Temperature Coefficient of Reference Voltage)
V
IN=15V, I
o
=0.1A, T
81
c
=0 to 100°C
V
IN=15V, I
o
c
=0 to 100°C
η
Efficiency
%
V
IN=15V, I
o
=0.5A
Conditions
V
V
IN=15V, I
o
=0.5A
=0.5A
fo
300
300
Oscillation Frequency
kHz
mV
mV
IN=15V, I
60
o
Conditions
Conditions
Conditions
Conditions
V
IN=15V, I
60
o
=0.5A
∆VOLINE
∆VOLOAD
80
40
80
40
Line Regulation
Load Regulation
V
V
IN=10 to 30V, I
10
o=0.5A
V
V
IN=10 to 30V, I
10
o=0.5A
IN=15V, Io=0.2 to 1.5A
IN=15V, Io=0.2 to 1.5A
I
S
1.6
1.6
Overcurrent Protection
Starting Current
A
V
V
IN=15V
V
IN=15V
Low Level Voltage
V
SSL
0.5
40
0.5
40
ON/OFF Pin*
I
I
I
SSL
10
10
Outflow Current at
Low Voltage
µA
V
SSL=0V
6
V
SSL=0V
6
Conditions
Conditions
Conditions
q
mA
V
IN=15V, I
200
o
=0A
V
IN=15V, I
200
o=0A
Quiescent Circuit Current
q(OFF)
400
400
µA
V
IN=15V, VSS=0V
VIN=15V, VSS=0V
*: 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 cur-
rent 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.
SI-8000TFE
SI-8000TFE
SI-8000TFE
5
SS
5
SS
C3
5 SS
C3
VO.ON/OFF
Soft start
Soft start
+VO.ON/OFF
ICs
36
ETC [ ETC ]
