SANKEN SI

1-1-3 DC/DC Converter ICs
SI-8000Q Series Surface Mount, Current Mode Cntrol Step-down Switching Mode
■Features
■Absolute Maximum Ratings
• Compact surface-mount package (HSOP8)
Symbol
Ratings
Unit
• Introduction of current mode control method
Input Voltage
VIN
30
V
• Output current: 3.5 A
Power Dissipation*1
PD
1.35
W
Junction Temperature*2
Tj
–30 to +150
°C
Storage Temperature
Tstg
–40 to +150
°C
Thermal Resistance(junction to case)
θ j-c
40
°C/W
Thermal Resistance(junction to ambient air)
θ j-a
74
°C/W
• High efficiency: 90% (Vo = 5 V)
• Built-in reference oscillator (500 kHz)
• A ceramic capacitor can be used for output
• Built-in drooping-type overcurrent and thermal
protection circuits
Parameter
Conditions
When mounted on glass-epoxy board, 30×30 mm (copper laminate area: 25×25 mm)
When mounted on glass-epoxy board, 30×30 mm (copper laminate area: 25×25 mm)
*1: Limited by thermal protection circuit
*2: Note that the detection 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
■Applications
• DVD recorder, FPD-TV
• Onboard local power supplies
• OA equipment
■Recommended Operating Conditions
Ratings
Parameter
Symbol
Unit
SI-8005Q
Vo+3*1
DC Input Voltage Range
VIN
Output Voltage Range
VO
0.5 to 24
to 28
Output Current Range
IO
0 to 3.5
A
Operating Junction Temperature Range
Tjop
–30 to +125
°C
Operating Temperature Range
Top
–30 to +85
°C
Conditions
V
V
*1: The minimum value of the input voltage range is 4.75 V or Vo +3 V, whichever is higher.
■Electrical Characteristics
(R1=4.2kΩ, R2=0.8kΩ when Ta = 25°C and Vo=5V)
Rating
Parameter
SI-8005Q
Symbol
min.
Reference Voltage
Temperature Coefficient of Reference Voltage
VADJ
0.485
Conditions
Oscillation Frequency
Line Regulation
Load Regulation
Overcurrent Protection Starting Current
∆VADJ/∆T
0.500
0.515
0.05
Conditions
VIN=12V, Io=1A, Ta=–40 to +85°C
Conditions
VIN=12V, Io=1A
450
Conditions
550
30
Conditions
60
VIN=8 to 28V, Io=1A
30
∆VOLOAD
Conditions
60
VIN=12V, Io=0.1 to 3.5A
3.6
Conditions
6.0
VIN=12V
Iq
18
Conditions
Outflow Current at Low Voltage
High Level Voltage
EN Pin
Low Level Voltage
Inflow Current at Low Low Voltage
20
Conditions
VIN=12V, Io=0A, VEN=0V
Conditions
VIN=16V, VSSL=0V
ISSL
5
Vc/EN
2.2
VIN=12V
Conditions
VEN=0V
IC/EH
mV
A
µA
V
VIN=12V
Vc/EL
Conditions
mV
µA
2.8
Conditions
kHz
mA
VIN=12V, Io=0A, VEN=open
Iq(OFF)
SS Pin
%
VIN=16V, Io=1A
∆VOLINE
IS
500
V
mV/ °C
90
fo
Quiescent Circuit Current
max.
VIN=12V, Io=1A
η
Efficiency
Unit
typ.
5
V
µA
Error Amplifier Voltage Gain
AEA
1000
V/V
Error Amplifier Transformer Conductance
GEA
800
µA/V
Current Sense Amplifier Impedance
1/GCS
0.35
V/A
Maximum ON Duty
DMAX
92
%
Minimum ON Time
DMIN
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-8008Q
8 SS
C8
30
ICs
Soft start
SI-8000Q Series
■External Dimensions (HSOP8)
Pin Assignment
1BS
2IN
3SW
4GND
5FB
6COMP
7EN
0.08±0.08
6.20
4.40
Pin 1 Mark
0.05±0.05
(Unit : mm)
Enlarged View of A
1.50
0.695 TYP
5.20
0.15
A
8SS
0.4
1.27
0.40
Plastic Mold Package Type
2.70
Flammability: UL 94V-0
2.90
Product Mass: Approx. 0.1 g
■Block Diagram
2
IN
Current
Sense
Amp
OSC
Boot
REG
OCP
5v_ldo
P.REG
1
BS
VREF
0.5V
PWM
LOGIC
ON
OFF
7
EN
OVP
TSD
Drive
3
SW
5v_ldo
6
COMP
5
FB
Amp
UVLO
0.5V
4
GND
8
SS
■Typical Connection Diagram
VIN
7
2
IN
1
BS
EN
C4
R1
SI-8000Q
8
C1
SS
GND
COMP
6
C5
C6
OPEN
C3
R3
VO
L1
SW 3
FB 5
D1
GND
4
VFB
C2
R2
IADJ
GND
C1:10µF/50V
(Murata:GRM55DB31H106KA87)
C2:22µF/16V
(Murata:GRM32ER71A226KE20)
C3:560pF*1
(Murata:GRM18 Type)
C4:10nF
(murata: GRM18 Type)
C5:10nF
(murata: GRM18 Type)
L1:10µH
D1: SPB-G56S (Sanken)
SJPB-L4 (Sanken)
R1:46kΩ (Vo=5V)
R2:5.1kΩ
R3:24kΩ *1
*1: When Vo=5V
ICs
31