SI-8001FDE DC-to-DC Step-Down Converter Features and Benefits Description ▪ 3.5 A output current supplied in a small, surface mount power package ▪ High efficiency: 83% at VIN = 15 V, IO = 2.0 A,VO = 5 V ▪ Requires only six external components (optional soft start requires an additional capacitor) ▪ Oscillation circuit built-in (frequency 300 kHz typical) ▪ Constant-current mode overcurrent protection circuit and overtemperature protection circuit built-in ▪ Soft start function built-in (can be implemented as an on/off function; output-off state at low level) ▪ Low current consumption during output-off state The SI-8001FDE DC voltage regulator is a DC-to-DC buck convertor that attains an oscillation frequency of 300 kHz, and has an integrated miniaturized choke coil, allowing it to serve as a small, high efficiency power supply in a compact TO263 package. Package: TO263-5 Applications include: ▪ DVD recorder ▪ FPD TV ▪ Telecommunications equipment ▪ Office automation equipment, such as printers ▪ On-board local power supply ▪ Output voltage regulator for second stage of SMPS (switched mode power supply) The internal switching regulator function provides high efficiency switching regulation without any need for adjustment. The device requires only six external support components. The optional soft start function requires an additional capacitor. Optional on/off control can be performed using a transistor. The SI-8001FDE includes overcurrent and overtemperature protection circuits. Not to scale Functional Block Diagram VIN 1 IN SW C1 PReg C3 On/Off Soft Start Latch and Driver C2 R1 Osc Comparator Overtemperature Protection Error Amplifier ADJ 4 R2 Reference Voltage GND 3 27469.056 VOUT L1 Di SPB-G56S (Sanken) Overcurrent Protection Reset 5 SS 2 SANKEN ELECTRIC CO., LTD. http://www.sanken-ele.co.jp/en/ SI-8001FDE DC-to-DC Step-Down Converter Selection Guide Part Number Output Voltage Adjustable Range (V) Efficiency, Typ. (%) Input Voltage, Max. (V) Output Current, Max. (A) Packing SI-8001FDE-TL 0.8 to 24 83 40 3.5 800 pieces per reel Absolute Maximum Ratings Characteristic Symbol Remarks DC Input Voltage VIN Power Dissipation PD Mounted on 40 mm × 40 mm exposed copper area on 40 mm × 40 mm glass-epoxy PCB; limited by internal overtemperature protection. Junction Temperature TJ Internal overtemperature protection circuit may enable when TJ ≥ 130°C. During product operation, recommended TJ ≤ 125°C. Storage Temperature Tstg Thermal Resistance (junction-to-case) RJC Mounted on 40 mm × 40 mm exposed copper area on 40 mm × 40 mm glass-epoxy PCB. Thermal Resistance (junction-to-ambient air) RJA Mounted on 40 mm × 40 mm exposed copper area on 40 mm × 40 mm glass-epoxy PCB. Rating Units 43 V 3 W –40 to 150 °C –40 to 150 °C 3 °C/W 33.3 °C/W Recommended Operating Conditions* Characteristic Symbol DC Input Voltage Range VIN DC Output Voltage Range VO DC Output Current Range IO Operating Junction Temperature Range TJOP Operating Temperature Range TOP Remarks VIN (min) is the greater of 4.5 V or VO+3 V. VIN ≥ VO + 3 V; to be used within the allowable package power dissipation characteristics (refer to Power Dissipation chart). To be used within the allowable package power dissipation characteristics (refer to Power Dissipation chart). Min. Max. Units See remarks 40 V 0.8 24 V 0 3.5 A –30 100 °C –30 85 °C *Required for normal device functioning according to Electrical Characteristics table. All performance characteristics given are typical values for circuit or system baseline design only and are at the nominal operating voltage and an ambient temperature, TA, of 25°C, unless otherwise stated. 27469.056 SANKEN ELECTRIC CO., LTD. 2 SI-8001FDE DC-to-DC Step-Down Converter ELECTRICAL CHARACTERISTICS1, valid at TA = 25°C, VO = 5 V (adjusted), R1 = 4.2 kΩ, R1 = 0.8 kΩ Characteristic Test Conditions1 Symbol Reference Voltage VADJ Reference Voltage Temperature Coefficient VIN = 15 V, IO = 0.2 A ∆VADJ /∆T Max. Units 0.816 V VIN = 15 V, IO = 0.2 A, TC = 0 to 100 °C – ±0.1 – mV/°C VIN = 15 V, IO = 2 A – 83 – % fO VIN = 15 V, IO = 2 A 270 300 330 kHz – – 80 mV Line Regulation VLine VIN = 10 to 30 V, IO = 2 A Load Regulation VLoad VIN = 15 V, IO = 0.2 to 3.5 A Overcurrent Protection Threshold Current Typ. 0.800 η Efficiency2 Operating Frequency Min. 0.784 IS VIN = 15 V SS Terminal On/Off Operation Threshold Voltage VSSL SS Terminal On/Off Operation Outflow Current ISSL Quiescent Current 1 Iq Quiescent Current 2 Iq(off) – – 50 mV 3.6 – – A – – 0.5 V VSSL = 0 V – 6 30 μA VIN = 15 V, IO = 0 A – 6 – mA VIN = 15 V, VSS = 0 V – 200 600 μA 1Using circuit shown in Typical Application Circuit diagram. 2Efficiency is calculated as: η(%) = ([V × I ] × [V × I ]) × 100. O O IN IN Pin-out Diagram Terminal List Table Name Number IN 1 Supply voltage Function SW 2 Regulated supply output GND 3 Ground terminal ADJ 4 Terminal for resistor bridge feedback The SS terminal is used to enable soft start and to control on/off operation of the IC output, VO (see figure 2). If neither soft start nor on/off control is used, leave pin open. SS 1 2 3 4 5 To enable soft start, connect a capacitor between SS and ground. To control on/off operation, connect an NPN bipolar transistor, in a TTL open collector output configuration, between the SS terminal and GND. Turn off is done by decreasing VSSL below its rated level. When both soft start and VO on/off are used, a protection measure such as current limiting is required because, if the capacitance of C3 large, the discharge current of C3 flows across the transistor for on/off operation. Because a pull-up type resistor is provided inside the IC, no external voltage can be applied. 5 SI-8000FDE SS 5 System TTL SI-8000FDE SI-8000FDE SS 5 SS 5 C3 System TTL (a) VO on/off control only (b) Soft start only C3 (c) VO on/off and soft start control Figure 2. Alternative configurations for SS pin. If neither soft start nor VO on/off is required, the SS pin is left open. 27469.056 SANKEN ELECTRIC CO., LTD. 3 SI-8001FDE DC-to-DC Step-Down Converter Performance Characteristics At TA = 25°C, VO = 5 V Adjusted, R1 = 4.2 kΩ, R2 = 0.8 kΩ 6.00 90 15 V Efficiency versus Output Current VO= 3.3 V η (%) 80 0.5 A VIN 4.00 Low Voltage Behavior: Output Voltage versus Supply Voltage 20 V 75 30 V 70 40 V VO (V) 8V 0 0.5 1.0 1.5 2.0 IO (A) 2.5 3.0 0 3.5 1 2 3 4 5 VIN (V) 5.08 15 V 85 VIN 6 7 8 VIN 5.06 5.04 80 20 V 75 40 V Load Regulation: 5.02 Output Voltage 5.00 versus Output Current 4.98 VO (V) η (%) 0 5.10 8V 30 V 70 30 V 15 V 10 V 4.96 40 V 4.94 65 60 3.5 A 1.00 90 Efficiency versus Output Current VO= 5.0 V 1A 2A 3.00 2.00 65 60 0A IO 5.00 85 8V 4.92 4.90 0 0.5 1.0 1.5 2.0 IO (A) 2.5 3.0 0 3.5 100 1 2 IO (A) 10 20 VIN (V) 3 10 95 20 V 15V VIN 8 Quiescent Current versus Supply Voltage IO = 0 A SS pin open 85 30 V 80 Iq (mA) Efficiency versus Output Current VO= 12.0 V η (%) 90 40 V 6 4 2 75 0 70 0 0.5 1.0 1.5 2.0 IO (A) 2.5 3.0 3.5 400 0 30 40 6 5 8V 300 Overcurrent Protection: Output Voltage versus Output Current 200 4 VO (V) IQ (μA) Behavior at Turn-Off: Quiescent Current versus Input Voltage IO = 0 A VSS = 0 V VIN 15 V 3 30 V 2 40 V 100 1 0 0 0 27469.056 0.5 1.0 1.5 2.0 VIN (V) 2.5 3.0 3.5 0 SANKEN ELECTRIC CO., LTD. 1 2 IO (A) 3 4 5 4 SI-8001FDE DC-to-DC Step-Down Converter Thermal Performance Characteristics The application must be designed to ensure that the TJ(max) of the device is not exceeded during operation. To do so, it is necessary to determine values for maximum power dissipation, PD(max), and ambient temperature, TA(max). Power Dissipation versus Ambient Temperature TJ(max) = 125°C; Mounted on glass-epoxy PCB (40 mm × 40 mm), with varying exposed copper areas 3.5 Cu Area: 1600 mm2 RθJA = 33.3°C/W The relationships of TJ, PD, TA, and case temperature, TC, are as shown in the following formulas: PD = TJ – TC RθJC and PD = TJ – TA RθJA 3.0 Cu Area: 800 mm2 RθJA = 37°C/W . 2.5 PD can be calculated from input values: ⎞ ⎟⎟ ⎠ Cu Area: 400 mm2 RθJA = 44°C/W 2.0 PD (W) ⎛ 100 ⎞ ⎛ V − 1⎟⎟ − VF ⋅ I O ⎜⎜1 − O PD = VO ⋅ I O ⎜⎜ ⎝ Hx ⎠ ⎝ VIN Cu Area: 100 mm2 RθJA = 53°C/W 1.5 where: VO is output voltage in V, 1.0 ηx is IC efficiency in percent (varies with VIN and IO; refer to efficiency performance curves for value), and VF is forward voltage for the input diode, Di. In these tests, the Sanken SPB-G56S was used, at 0.4 V. For application design, obtain thermal data from the datasheet for the diode. PD is substantially affected by the heat conductance properties of the application, in particular any exposed copper area on the PCB where the device is mounted. The relationships of PD, TA, and copper area is represented in the Power Dissipation chart. RθJA for a given copper area can be determined form the Device Thermal Resistance chart. This can be substituted into the formula above to determine the TJ (max) allowable in the application. Generally, more than 10% to 20% derating is required. Because the heat dissipation capacity of the copper area depends substantively on how it is used in the actual application, thermal characteristics of the application must be confirmed by testing. TC is determined by connecting a thermocouple to the device as shown here: Thermocouple mount at tab center 0.5 0 –25 0 25 75 100 125 Device Thermal Resistance versus Exposed Copper Area on PCB Glass-epoxy PCB, 40 mm × 40 mm 55 50 45 40 35 30 0 200 400 600 800 1000 1200 1400 1600 1800 Copper Area (mm2) 6 OTP On 5 Overtemperature Protection: Output Voltage versus Junction Temperature VIN = 15 V, IO = 10 mA And analyzing the results using the following formula: TJ = PD × RθJC + TC , for this device, RθJC is 3 °C/W. 27469.056 50 TA (°C) SANKEN ELECTRIC CO., LTD. 4 VO (V) IO is output current in A, RθJA(°C/W) VIN is input supply voltage in V, 3 2 1 OTP Off 0 0 20 40 60 80 100 TJ (°C) 120 140 160 180 5 SI-8001FDE DC-to-DC Step-Down Converter Component Selection Diode Di A Schottky-barrier diode must be used for Di. If other diode types are used, such as fast recovery diodes, the IC may be destroyed because of the reverse voltage applied by the recovery voltage or ON voltage. Choke Coil L1 If the winding resistance of the choke coil is too high, the efficiency may be reduced below rating. Because the overcurrent protection start current is approximately 4.2 A, attention must be paid to the heating of the choke coil by magnetic saturation due to overload or short-circuited load. Capacitors C1, C2, and C3 Because for SMPS, large ripple currents flow across C1 and C2, capacitors with high frequency and low impedance must be used. If the impedance of C2 is too high, the switching waveform may not be normal at low temperatures. Do not use either OS or tantalum types of capacitors for C2 or C3, because the extremely low ESR causes an abnormal oscillation. The device is stabilized, and for proper operation, C1 must be located close to the device (see layout diagram, below). C3 is required only if the soft start function is used. If not using softstart, leave the SS terminal open. A pull-up resistor is provided inside the IC. Resistor Bridge R1 and R2 comprise the resistor bridge for the output voltage, VO, and are calculated as follows: (V − V ) (V − 0.8) (Ω) , and R2 = VADJ = 0.8 = 0.8 (k Ω ) R1 = O ADJ = O −3 −3 1 × 10 IADJ 1 × 10 IADJ IADJ should always be set to 1 mA. Note that R2 should always be present to ensure stable operation, even if VO, is set to 0.8 V (that is, even if there is no R1). VO should be at least VIN + 8%. Typical Application Diagram VIN 1 IN SW L1 2 SI-8001FDE SS GND 3 5 C1 GND ADJ VO R1 4 IADJ Di C3 Soft Start Only R2 C2 Component C1 C2 C3 Di L1 Rating 470 μF 680 μF 0.1 μF (For soft start function) SPB-G56S (Sanken) 47 μH GND Recommended PCB Layout Recommended Solder Pad Layout 11±0.2 9±0.2 6.8±0.1 9±0.1 3.7±0.05 4±0.1 1±0.05 All external components should be mounted as close as possible to the SI-8001FDE. The ground of all components should be connected at one point near GND pin (pin 3). 27469.056 SANKEN ELECTRIC CO., LTD. 1.7±0.1 (mm) 6 SI-8001FDE DC-to-DC Step-Down Converter 9.90 ±0.20 0.80 ±0.10 2.00 ±0.10 3º (R0.30) (0.50) 6º 0º 4×P1.70 ±0.25 2.40 ±0.20 2.54 ±0.30 0.88 ±0.10 0.10 ±0.15 3º (0.75) 4.90 ±0.20 XXXXXXXX + (R0.45) 3XR0.30 15.30 ±0.30 XXXXXXXX XXXXXXXX Branding (4.40) + 3º 9.20 ±0.20 XXXXXXXX (4.60) Ø1.5 ±0.20 (0.40) 1.30 –0.05 (0.75) +0.10 3XR0.30 15º (8.00) (6.80) 4.50 ±0.20 2.20 ±0.20 PACKAGE OUTLINE DRAWING 2XR0.30 3º 1 2 3 4 10.00 ±0.02 5 Branding codes (exact appearance at manufacturer discretion): Dimensions do not include mold protrusion Heastsink side flash: 0.8 mm maximum Dimensions in millimeters 1st line: SK 2nd line, lot: YMW X Where: Y is the last digit of the year of manufacture M is the month (1 to 9, O, N, D) W is the week of the month (1 to 5) X is the device subtype suffix number 3rd line, type: 8001FDE RoHS directive compliant Device pins lead (Pb) free 27469.056 SANKEN ELECTRIC CO., LTD. 7 SI-8001FDE DC-to-DC Step-Down Converter 27469.056 solder bath must be grounded in other to prevent leak voltages generated by them from being applied to the products. • The products should always be stored and transported in our shipping containers or conductive containers, or be wrapped in aluminum foil. Soldering • When manually soldering the products, please be sure to minimize the working time, within the following limits: Soldering Iron Temperature (°C) Time (s) 380±10 3 (once only) • Reflow soldering can be performed a maximum of twice, using the following recommended profile: 250°C Maximum 250 230 Temperature (°C) Cautions for Use • Operation of the product in parallel to increase current is not permitted. • Although the product has an internal overtemperature protection circuit, that is intended only to protect the product from temporary excess heating due to overloads. Long-term reliability cannot be guaranteed when the product is operated under continuous overload conditions. Because reliability can be affected adversely by improper storage environments and handling methods, please observe the following cautions. Cautions for Storage • Ensure that storage conditions comply with the standard temperature (5°C to 35°C) and the standard relative humidity (around 40 to 75%); avoid storage locations that experience extreme changes in temperature or humidity. • Avoid locations where dust or harmful gases are present and avoid direct sunlight. • Reinspect for rust on leads and solderability of products that have been stored for a long time. Cautions for Testing and Handling When tests are carried out during inspection testing and other standard test periods, protect the products from power surges from the testing device, shorts between adjacent products, and shorts to the heatsink. Electrostatic Discharge • When handling the products, operator must be grounded. Grounded wrist straps worn should have at least 1 MΩ of resistance to ground to prevent shock hazard. • Workbenches where the products are handled should be grounded and be provided with conductive table and floor mats. • When using measuring equipment such as a curve tracer, the equipment should be grounded. • When soldering the products, the head of soldering irons or the 180 30 ±10s 150 SANKEN ELECTRIC CO., LTD. 90 ±30s Time 8 SI-8001FDE DC-to-DC Step-Down Converter • The contents in this document are subject to changes, for improvement and other purposes, without notice. Make sure that this is the latest revision of the document before use. • Application and operation examples described in this document are quoted for the sole purpose of reference for the use of the products herein and Sanken can assume no responsibility for any infringement of industrial property rights, intellectual property rights or any other rights of Sanken or any third party which may result from its use. • Although Sanken undertakes to enhance the quality and reliability of its products, the occurrence of failure and defect of semiconductor products at a certain rate is inevitable. Users of Sanken products are requested to take, at their own risk, preventative measures including safety design of the equipment or systems against any possible injury, death, fires or damages to the society due to device failure or malfunction. • Sanken products listed in this document are designed and intended for the use as components in general purpose electronic equipment or apparatus (home appliances, office equipment, telecommunication equipment, measuring equipment, etc.). When considering the use of Sanken products in the applications where higher reliability is required (transportation equipment and its control systems, traffic signal control systems or equipment, fire/crime alarm systems, various safety devices, etc.), and whenever long life expectancy is required even in general purpose electronic equipment or apparatus, please contact your nearest Sanken sales representative to discuss, prior to the use of the products herein. The use of Sanken products without the written consent of Sanken in the applications where extremely high reliability is required (aerospace equipment, nuclear power control systems, life support systems, etc.) is strictly prohibited. • In the case that you use Sanken products or design your products by using Sanken products, the reliability largely depends on the degree of derating to be made to the rated values. Derating may be interpreted as a case that an operation range is set by derating the load from each rated value or surge voltage or noise is considered for derating in order to assure or improve the reliability. In general, derating factors include electric stresses such as electric voltage, electric current, electric power etc., environmental stresses such as ambient temperature, humidity etc. and thermal stress caused due to self-heating of semiconductor products. For these stresses, instantaneous values, maximum values and minimum values must be taken into consideration. In addition, it should be noted that since power devices or IC's including power devices have large self-heating value, the degree of derating of junction temperature affects the reliability significantly. • When using the products specified herein by either (i) combining other products or materials therewith or (ii) physically, chemically or otherwise processing or treating the products, please duly consider all possible risks that may result from all such uses in advance and proceed therewith at your own responsibility. • Anti radioactive ray design is not considered for the products listed herein. • Sanken assumes no responsibility for any troubles, such as dropping products caused during transportation out of Sanken's distribution network. • The contents in this document must not be transcribed or copied without Sanken's written consent. 27469.056 SANKEN ELECTRIC CO., LTD. 9