1-1-2 Switching Mode Regulator ICs SI-8000GL Series Compact, Separate Excitation Step-down Switching Mode Regulator ICs ■Features ■Absolute Maximum Ratings • DIP 8 pin package • Output current: 1.5A • High efficiency: 86% (at VIN = 20V, lO = 1A, VO = 5V) • Capable of downsize a choke-coil due to IC's high switching frequency (250kHz). (Compared with conventional Sanken devices) • The output-voltage-variable type can vary its output voltage from 1V to 14V because of its low reference voltage (Vref) of 1V. • Wide Input Voltage Range (8 to 50V) • Output ON/OFF available • Built-in overcurrent protection and thermal protection circuits Symbol Ratings DC Input Voltage Parameter VIN 53 Unit V Power Dissipation PD*1 1 W °C Junction Temperature Tj +125 Storage Temperature Tstg –40 to +125 °C Thermal Resistance (junction to case) θ j-c 28 °C/W Thermal Resistance (junction to ambient air) θ j-a 100 °C/W *1: Limited by thermal protection. ■Applications • Onboard local power supplies • OA equipment • For stabilization of the secondary-side output voltage of switching power supplies ■Recommended Operating Conditions Ratings Symbol Parameter SI-8010GL (8 or VO+3)*1 to 50 DC Input Voltage Range VIN Output Voltage Range VO 1 to 14 Output Current Range IO 0.02 to 1.5 Operating Junction Temperature Range Tjop –30 to +125 Operating Temperature Range Top –30 to +125 *1: The minimum value of an input voltage range is the higher of either 8V or VO+3V. ■Electrical Characteristics (Ta=25°C) Ratings Parameter Symbol SI-8010GL (Variable type) min. Reference Voltage 0.97 FOSC Conditions Temperature Coefficient of Reference Voltage Overcurrent Protection Starting Current Quiescent Circuit Current Circuit Current at Output OFF 40 VIN=10 to 30V, IO=1A ∆VOLOAD 10 Conditions 30 VIN=12V, IO=0.1 to 1.5A 1.6 Conditions Iq Conditions 7 400 VIN=12V, VON/OFF=0.3V VSSL 0.5 Terminal Outflow Current at Low Voltage ISSL 50 *: Pin 2 is the CE/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. CE/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 C4 flows into the ON/OFF control transistor. Therefore, limit the current securely to protect the transistor if C3 capacitance is large. The CE/SS pin is pulled up to the power supply in the IC, so applying the external voltage is prohibited. VSSL=0V ICs µA V µA SI-8000GL SI-8000GL SI-8000GL 2 CE/SS 2 CE/SS 2 CE/SS C4 VO. ON/OFF 68 mA VIN=12V, IO=0A Low Level Voltage Conditions mV A VIN=12V Iq(OFF) Conditions mV mV/°C ±0.5 ∆VREF/∆Ta IS kHZ VIN=12V, IO=1A 20 V % 250 Conditions Load Regulation 1.03 VIN=20V, IO=1A, VO=5V ∆VOLINE Line Regulation 1.00 86 Conditions Oscillation Frequency max. VIN=12V, IO=1A Eff Efficiency CE/SS* Terminal VREF Conditions Unit typ. Soft start C4 Soft start +VO. ON/OFF SI-8000GL Series ■External Dimensions (DIP8) 7 6 a 6.5±0.2 8 (Unit: mm) 5 8010GL SK b Pin Assignment 1. GND 2. CE/SS 3. Reg 4. SWOUT 5. VIN 6. B.S 7. Comp 8. VREF c 1 2 3 4 1.0+0.3 -0.05 1.5+0.3 -0.05 7.6 7.5±0.5 4.2±0.3 3.4±0.1 9.4±0.3 +0.1 0.25-0. 05 3.3±0.2 Plastic Mold Package Type Flammability: UL 94V-0 Product Mass: Approx. 0.49 g 0.5±0.1 0.25 M 2.54 0°∼15° 0.89 TYP ■Block Diagram ■Ta-PD Characteristics SI-8010GL 2 PD=VO • IO 1.8 UVLO CE/SS P.REG Power Dissipation PD (W) VIN OCP CE/SS BS Boot REG TSD DRIVE Reg OSC + PWM LOGIC - SWOUT 100 VO –1 –VF • IO 1– ηχ VIN 1.6 Note 1: The efficiency depends on the input voltage and the output current. Therefore, obtain the value from the efficiency graph and substitute the percentage in the formula above. Note 2: Thermal design for D1 must be considered separately. 1.4 1.2 1 θ j-a:100°C/W 0.8 0.6 0.4 0.2 0 –25 VREF Comp Amp + 0 25 50 75 100 125 Ambient Temperature Ta (°C) 1V GND VO : Output voltage VIN : Input voltage IO : Output current ηχ : Efficiency VF : Diode D1 forward voltage RK16···0.4V(IO=1A) ■Typical Connection Diagram SI-8010GL C1: 220µF/63V C2: 470µF/25V C3: 0.1µF C4: 1000pF C5: 0.1µF C6: 0.047µF C7: 0.1µF 6 B.S R1 L1 C3 5 VIN VIN SI-8010GL SWOUT V0 4 2 C1 + Reg 3 C4 GND D1 R2 CE/SS C7 Comp 7 C5 GND 1 VREF + C2 8 R3 C8 IREF C8: 0.1µF R1: 47Ω L1: 47µH D1: RK16 (Sanken) C6 GND R2= (VOUT–VREF) (VOUT–1) 1 VREF .= = = (Ω), R3 = . 500(Ω) IREF 2×10–3 IREF 2×10–3 Diode D1 • Be sure to use a Schottky-barrier diode as D1. If other diodes like fast recovery diodes are used, IC may be destroyed because of the reverse voltage generated by the recovery voltage or ON voltage. Choke coil L1 • If the winding resistance of the choke coil is too high, the efficiency may drop below the rated value. • As the overcurrent protection starting current is approx. 2.5 A, take care concerning heat radiation from the choke coil caused by magnetic saturation due to overload or short-circuited load. Capacitor C1, C2 • As large ripple currents flow through C1 and C2, use high-frequency and low-impedance capacitors aiming for switching-mode-power-supply use. Especially when the impedance of C2 is high, the switching waveform may become abnormal at low temperatures. For C2, do not use a capacitor with an extremely low equivalent series resistance (ESR) such as an OS capacitor or a tantalum capacitor, which may cause an abnormal oscillation. Resistors R2, R3 • R2 and R3 are the resistors to set the output voltage. Set their values so that IREF becomes approx. 2 mA. Obtain R2 and R3 values by the following formula above. * To create the optimum operating conditions, place the components as close as possible to each other. ICs 69 ●SI-8000GL Series ■Example of Pattern on PC Board SI-8010GL C9 C6 VIN R2 R3 + C1 C7 C2 R1 + GND C3 C4 D1 L1 V0 C8 C5 Recommended Pattern *For the optimum conditions, use one-point GND wiring centering on pin 1, and place each component as closely as possible. ■Ta-PD Characteristics PD=VO • IO Power Dissipation PD (W) 1.8 100 VO –1 –VF • IO 1– ηχ VIN 1.6 Note 1: The efficiency depends on the input voltage and the output current. Thus, obtain the value from the efficiency graph and substitute the percentage in the formula above. Note 2: Thermal design for D1 must be considered separately. 1.4 1.2 θ j-a:100°C/W 1 0.8 0.6 0.4 0.2 0 –25 0 25 50 75 100 125 Ambient Temperature Ta (°C) VO : Output voltage VIN : Input voltage IO : Output current ηχ : Efficiency VF : Diode forward voltage RK16···0.4V(IO=1A) ■Packaging specifications (Unit: mm) Minimum package Stick Qty: 50 pcs/1 stick Stopper (with fin) 11.6±0.2 5.7±0.2 5.0±1.0 4.2±0.15 13±0.2 505±1.0 Stopper (without fin) 50pcs 5 ●SI-8000GL Series ■Typical characteristics (SI-8010GL) Efficiency Characteristics Output Voltage Ta=25°C 100 VO=24V Ta=25°C 1.03 1.0 Output Voltage VO (V) 80 IO=1.5A 1A VO=1.8V 0.5A IO=1.5A 60 1.02 Output Voltage VO (V) 1A 0.5A VO=5V Efficiency η (%) 1.2 IO=1.5A 90 70 Load Regulation *Load=C.R Ta=25°C 0.8 IO=0.02A 1A 1.5A 0.6 0.4 0.2 1.01 VIN=8V 12V 1.00 20V 30V 0.99 0.98 1A 10 20 30 40 0 50 0 Overcurrent Protection Characteristics 10 15 20 VIN=30V 20V 12V 8V 1.0 Output Voltage VO (V) Output Voltage VO (V) 0.8 0.6 0.4 1 2 3 Output Current IO (A) 6 0.8 0.6 TSD OFF TSD ON 0.4 0.2 0.2 0 0 4 0 50 100 150 Ambient Temperature Ta (°C) 0.5 1.0 1.5 Temperature Characteristics VIN=12V, IO=0.02A 1.2 1.0 0 0.97 Output Current IO (A) Thermal Protection Characteristics Ta=25°C 1.2 5 Input Voltage VIN (V) Input Voltage VIN (V) 200 VIN=12V, IO=1A 300 Freq 250 200 1.015 1.01 1.005 150 1 VO 100 50 –50 0.995 η 0 50 100 Ambient Temperature Ta (°C) 0.99 150 Output Voltage VO (V) 0.5A 0 Frequency Freq (kHz) Efficiency η (%) 50