1-1-3 DC/DC Converter ICs SI-8000FFE Series Full-Mold, Separate Excitation Step-down Switching Mode Features Lineup * Compact full-mold package (equivalent to TO220) * Output current: 3.5 A Part Number SI-8001FFE Variable (0.8 to 24) Vo (V) Io (A) 3.5 Function Soft start * High efficiency: 83% (Vo = 5 V, VIN = 15 V, Io = 2 A) * Requires only 6 discrete components * Built-in reference oscillator (300 kHz) * Built-in drooping-type overcurrent and thermal protection circuits * Built-in soft start circuit (Output ON/OFF available) Applications Absolute Maximum Ratings Parameter Symbol Input Voltage Ratings VIN 43 Power Dissipation PD1-1 22.7 (With infinite heatsink) PD1-2 18.2 Power Dissipation PD2-1 2.15 (Without heatsink) PD2-2 1.72 Tj +150 Junction Temperature*1 Unit SI-8001FFE V Limited by thermal protection circuit, Tj=150C W Tj=125C Limited by thermal protection circuit, Tjmax=150C W Tj=125C C * DVD recorder, FPD-TV Storage Temperature Tstg -40 to +150 C * OA equipment, such as printers Thermal Resistance (Junction to Case) j-c 5.5 C/W Thermal Resistance (Junction to Ambient Air) j-a 58 C/W * Onboard local power supplies Conditions *: This product has built-in thermal protection circuits that may activate when the junction temperature exceeds 130C. The recommended design for the junction temperature during IC operation is below 125C. Recommended Operating Conditions Parameter Ratings Symbol Unit SI-8001FFE Vo+3*1 Input Voltage Range VIN Output Voltage Range VO 0.8 to 24 to 40 V 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 V *: The minimum value of the input voltage range is 4.5 V or Vo +3 V, whichever is higher. Electrical Characteristics (R1=4.2k, R2=0.8k when Ta=25C and Vo=5V) Ratings Parameter Symbol SI-8001FFE min. VADJ Reference Voltage 0.784 Conditions Temperature Coefficient of Reference Voltage Oscillation Frequency VIN=15V, Io=0.2A, Tc=0 to 100C Conditions VIN=15V, Io=2A fo 270 Outflow Current at Low Voltage IS kHz 80 mV VIN=10 to 30V, Io=2A 15 50 mV VIN=15V, Io=0.2 to 3.5A 3.6 Conditions A VIN=15V VSSL ISSL 6 Conditions VIN=15V, VSS=0V Conditions VIN=15V, Io=0A 0.5 V 30 A 6 Iq(OFF) mA 200 600 A 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 current securely to protect the transistor if C3 capacitance is large. The SS pin is pulled up (3.7 V typ.) to the power supply in the IC, so applying the external voltage is prohibited. If this pin is not used, leave it open. SI-8000FFE 5 SS SI-8000FFE 5 SS C3 VO.ON/OFF ICs 330 55 Conditions 44 % VIN=15V, Io=2A Iq Quiescent Circuit Current mV/ C 300 Conditions Conditions Low Level Voltage SS Pin V 83 VOLOAD Overcurrent Protection Starting Current 0.816 Conditions Conditions Load Regulation 0.800 0.1 VADJ/T VOLINE Line Regulation max. VIN=15V, Io=0.2A Efficiency Unit typ. http://store.iiic.cc/ Soft start SI-8000FFE 5 SS C3 Soft start +Vo. ON/OFF SI-8000FFE Series External Dimensions (TO220F-5) (Unit : mm) 0.2 4.2 0.2 2.8 0.2 4.00.2 7.90.2 3.20.2 0.5 10.0 q IN w SW e GND r ADJ t SS (17.9) 16.90.3 Pin Assignment (2.0) 2.60.1 Plastic Mold Package Type 0.950.15 Flammability: UL 94V-0 4.60.6 (4.6) +0.2 0.85 -0.1 Product Mass: Approx. 2.3 g +0.2 P1.70.7x4=6.80.7 0.45 -0.1 3.90.7 (4.3) 8.20.7 1 2 3 4 5 Block Diagram 1 SW IN PReg. 2 OCP 5 SS ON/OFF Soft start Latch & Drive Reset OSC + - ADJ TSD Comp. Error Amp. 4 - + + VREF GND 3 Typical Connection Diagram L1 1 VIN SW IN SI-8001FFE + C1 SS 5 2 VOUT R1 ADJ 4 GND 3 + C2 R2 Di IADJ C3 GND GND C1 C2 C3 L1 D1 :470F :680F :0.1F(Only when using soft-start function) :47H :RK46(Sanken) http://store.iiic.cc/ ICs 45