1-1-3 DC/DC Converter ICs
SI-8100QL Series Current Mode Control Step-down Switching Mode
■Features
• DIP8 package
■Absolute Maximum Ratings
Parameter
Symbol
Ratings
Unit
V
Conditions
Input Voltage
Power Dissipation*1
Junction Temperature*2
VIN
30
• Introduction of current mode control method
• Output current: 3.5A
PD
1.56
W
When mounted on glass-epoxy board measuring 70×60 mm (copper laminate area: 1310 mm2)
Tj
–30 to +150
–40 to +150
25
°C
• High efficiency: 90% (Vo=5V)
• Built-in reference oscillator (350kHz)
Storage Temperature
Tstg
θj-c
θj-a
°C
Thermal Resistance (Junction to Case)
Thermal Resistance (Junction to Ambient Air)
°C/W
°C/W
64
When mounted on glass-epoxy board measuring 70×60 mm (copper laminate area: 1310 mm2)
• Built-in drooping-type overcurrent and thermal
protection circuits
*1: Limited by thermal protection circuit
*2: Note that the detect temperature for thermal protection is about 140°C.
• Built-in soft start circuit
• Built-in on/off function (Active Hi)
• Low current consumption during off
■Recommended Operating Conditions
Ratings
Parameter
Symbol
Unit
Conditions
SI-8105QL
Vo+3*1 to 28
0.5 to 24
■Applications
• DVD recorder, FPD-TV
• Onboard local power supplies
• OA equipment
Input Voltage Range
VIN
Vo
V
V
Output Voltage Range
Output Current Range
Operating Junction Temperature Range
Operating Temperature Range
Io
0 to 3.5
A
Tjop
Top
–30 to +125
–30 to +85
°C
°C
*1: The minimum value of the input voltage range is 4.75 V or Vo +3 V, whichever is higher.
■Electrical Characteristics
(When Ta=25°C and Vo=5V)
Ratings
Parameter
Symbol
VADJ
SI-8105QL
Unit
min.
typ.
max.
0.485
0.500
0.515
V
mV/°C
%
Reference Voltage
Conditions
(∆VADJ/∆T)
Conditions
VIN=12V, Io=1A
0.05
Temperature Coefficient of Reference Voltage
Efficiency
VIN=12V, Io=1A, Ta=–40 to +85°C
η
90
VIN=12V, Io=1A
350
Conditions
Conditions
fo
315
3.6
385
60
kHz
mV
mV
A
Oscillation Frequency
VIN=16V, Io=1A
30
∆VoLINE
Line Regulation
Conditions
VIN=8 to 28V, Io=1A
30
∆VoLOAD
60
Load Regulation
Conditions
VIN=12V, Io=0.1 to 3.5A
Is
Iq
6.0
Overcurrent Protection Starting Current
Conditions
Conditions
VIN=12V
18
mA
µA
VIN=12V, Io=0A, VEN=open
Quiescent Circuit Current
Iq(OFF)
20
Conditions
VIN=12V, Io=0A, VEN=0V
ISSL
VC/EH
VC/EL
IC/EH
5
µA
SS Pin
EN Pin
Outflow Current at Low Voltage
High Level Voltage
Conditions
Conditions
Conditions
Conditions
VIN=12V, VSSL=0V
2.8
V
VIN=12V
2.2
V
Low Level Voltage
VIN=12V
5
µA
Inflow Current at Low Voltage
VEN=0V
1000
800
Error Amplifier Voltage Gain
Error Amplifier Transformer Conductance
Current Sense Amplifier Impedance
Maximum ON Duty
AEA
GEA
V/V
µA/V
V/A
1/GCS
DMAX
DMIN
0.35
92
%
Minimum ON Time
100
nsec.
*: Pin 8 is the SS pin. Soft start at power on can be performed with a capacitor connected to this pin.
The SS pin is pulled up to the power supply in the IC, so applying the external voltage is prohibited.
SI-8100QL
8
SS
C5
Soft start
ICs
42
ETC [ ETC ]
