1-1-1 Linear Regulator ICs
■Block
Diagram
●SI-3010KM/SI-3012KM
●SI-3025KM/SI-3033KM/SI-3050KM/SI-3090KM/SI-3120KM
V
IN
2
4 V
OUT
V
IN
2
4 V
O
5
V
C
1
-
+
5 ADJ
TSD
V
C
1
-
+
Sense
TSD
REF
3 GND
REF
3 GND
■Typical
Connection Diagram
●SI-3025KM/SI-3033KM/SI-3050KM/
SI-3090KM/SI-3120KM
●SI-3010KM/SI-3012KM
D1
*2
*1
D1
*2
*1
V
IN
2
+
V
O
4
+
V
IN
2
+
V
O
4
R1
+
C
IN
V
C
1
sense
GND 5
3
Load
C
O
C
IN
V
C
GND ADJ
1
5
3
C
O
R2
C
IN
: Input capacitor (22
µ
F or larger)
C
O
: Output capacitor
*1: SI-3012KM/3025KM/3033KM (22
µ
F or larger)
It comes with a circuit configuration that uses a low ESR capacitor for the output
capacitor.
If an electrolytic capacitor is used, oscillation may occur at a low temperature.
SI-3010KM/3050KM/3090KM/3120KM (47
µ
F or larger)
If a low ESR capacitor is used, oscillation may occur.
*2: D1: Reverse bias protection diode
This diode is required for protection against reverse biasing between the input
and output.
(Sanken SJPL-H2 is recommended.)
This diode is not required at V
O
≤
3.3 V.
R1, R2: Output voltage setting resistors
Output voltage can be set by connecting R1 and R2 as shown
above.
R2: 10 kΩ is recommended (24 kΩ for SI-3012KM).
R1=(V
O
–V
ADJ
)
÷
(V
ADJ
/R2)
*3: For SI-3010KM, insert R3 in case of setting V
O
to V
O
≤
1.5V.
Recommended value for R3 is 10kΩ.
■Reference
Data
Copper Laminate Area-Thermal Resistance
Glass-epoxy board : 30×30mm
100
90
Power Dissipation P
D
(W)
Copper Laminate Area-Power Dissipation
Glass-epoxy board : 30×30mm
1.5
Ta=25°C
1
40°C
60°C
0.5
85°C
0
θ
j-a(°C/W)
80
70
60
50
40
10
100
Copper Laminate Area (mm
2
)
1000
• Obtaining the junction temperature
Measure the temperature T
C
at the lead part
of the GND pin with a thermocouple, etc.
Then, substitute this value in the following
formula to obtain the junction temperature.
T
j
=P
D
× θ
j–C
+ T
C
Load
(
θ
j–C
= 6
°
C/W)
10
100
Copper Laminate Area (mm )
2
1000
Case temperature Tc
measurement point
18
ICs
SANKEN [ SANKEN ELECTRIC ]
