STR20000 Series Switching Type Chopper • Self Oscillation Type Features ● ● ● ● ● Requires only 4 external components Small size and high efficiency Low switching noise Variable output voltage Use of Sanken semiconductors components ensures high reliability Applications ● For power supplies in office equipment such as electronic typewriters, printers and copiers ● For power supplies in VCRs, personal CB radios (fixed stations), etc. External View ■ Absolute Maximum Ratings (Ta=25°C) Parameter Ratings Symbol Unit STR20005 DC Input Voltage VIN 45 V DC Output Current IO 2.0 (pulse 3.0) A Power Dissipation PD Operating Temperature Top –20 to +100 °C Storage Temperature Tstg –20 to +125 °C Rth(j-c) 1.8 °C/W Thermal Resistance (junction-to-case) 55 (TC=25°C) W 13 (TC=100°C) ■ Electrical Characteristics (Ta=25°C) Ratings Parameter Symbol STR20005 min DC Input Voltage Range Output Voltage Efficiency Line Regulation Load Regulation Ripple Rejection Switching Frequency 12 VIN 8 Condition VO Condition η Condition typ IO=1.0A 5.0 5.1 72 50 VIN=15 to 25V, IO=1.0A 100 VIN=20V, IO=0.5 to 1.5A 45 Condition f=100 to 120Hz f 30 VIN=20V, IO=1.0A V V % VIN=20V, IO=1.0A RREJ Condition 5.2 VIN=20V, IO=1.0A ∆VOLOAD Condition max 40 ∆VOLINE Condition Unit mV mV dB kHz ■ Outline Drawing/Terminal Connections (unit: mm) 4.5±0.2 ±0.3 15.4 ±0.2 5° 2.0±0.1 +0.2 2.54 ±0.1 ±0.1 3.81 3.81 Plastic Mold Package Type Flammability: UL94V-0 Terminal Connections q Output Voltage Adjustment w Output Voltage Detection e Switching Output (backside of case) r Input t Ground 1.0±0.1 +0.2 0.6 –0.1 ±0.1 1.6±0.2 5° 5° 3.4max. 1.2±0.15 28.0±0.3 7.0±0.2 Type Lot number 23.0±0.3 (38.0) (43.0) STR (15.0) 36° 3.2±0.1 5.0±0.2 3.2±0.2 (18) 9.9 0.6 –0 Weight: Approx. 8.2 g ±0.1 2.54 (7.62) (12.7) 17.8±0.3 4.0±0.1 5° 5° Note: Dimensions marked with * are measured at the roots of the leads. q w e r t ■ Block Diagram 4 ■ Standard External Circuit 3 Tr1 L=200µH R1 VIN DC Input 2 R3 R2 MIC1 R4 + 1000µF VOUT DC Output 3 4 2 5 VR1 1 VR2 1 Start Circuit + Di RU3M GND Reference Voltage C1 R5 1000µF GND Use VR1 and VR2 only when adjusting the output voltages. VR1 : Vout down VR2 : Vout up RU3M forward voltage : 0.7V 5 ■ Typical Operating Characteristics Ta=25°C 10 8 Efficiency η (%) Output Voltage VO (V) Efficiency Characteristics 6 IO 0A 1A 4 2A 2 0 0 2 4 6 8 10 12 14 16 18 20 Input Voltage VIN (V) Ta=25°C 100 90 80 70 60 50 40 30 20 10 0 Ta-PD Characteristics VIN 8V 20V 30V 40V 0 0.5 1 1.5 2 Output Current IO (A) 25 Power Dissipation PD (W) Rise Characteristics 2.5 Without Mica With Silicone Grease Heatsink: Aluminum Unit: mm 20 150×150×2 (3.3°C/w) 15 100×100×2 (5.2°C/w) 10 5 75×75×2 (7.6°C/w) Without heatsink 0 –20 0 20 40 60 80 100 Ambient Temperature Ta (°C) 13