SP3613. Order Information PIN CONFIGURATIONN PIN NAME DISCRIPTION TYPICAL APPLICATION. 1 VIN Input

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1 60, 3A STEP DOWN OLTAGE SWITCHING REGULATOR DESCRIPTION The SP3613 series is designed to provide all the active function for a step-down (buck) switching regulator, and drives a maximum load current as high as 3A line and load regulations. SP3613 is available in fixed output voltages of 5 and a versatile Adjustable output version. These regulators are simple to use and require minimum number of external components. The features include internal frequency compensation and a fixed-frequency oscillator. The SP3613 is high-efficiency replacements for popular three-terminal linear regulators, and is requiring a smaller heat sink or even no need heat sink. SP3613 performs well with standard inductors from most of manufacturers, and simplifying the design of switch-mode power supplies. External shutdown is included with 80µA (typical) standby current. The output switch has cycle-by-cycle current limiting as well as thermal shutdown for full protection under fault conditions. SP3613 operates at a switching frequency of 52 khz which allowing smaller size filter components than what would be needed with lower frequency switching regulators.sp3613 series are available in a standard 5-lead TO263 package. FEATURES Adjustable version output voltage range 1.23 to 57 out accuracy is up to ±2% under specified input voltage the output load conditions Input voltage range up to 60 Requires only 4 external components with High efficiency TTL shutdown capability, low power standby mode Built-in thermal shutdown, current limit protection Uses standard inductors 52 khz fixed frequency internal oscillator May Rev.1.0 Page1-6

2 60, 3A STEP DOWN OLTAGE SWITCHING REGULATOR PIN CONFIGURATIONN PIN NAME DISCRIPTION 1 IN Input 2 Output Inductor Connection. Connect an inductor Between Pin and the regulator output. 3 GND Ground. Connect this pin to the PCB ground. 4 Feedback Feedback Input. 5 ON/OFF Enable pin ORDER/MARKING INFORMATION Order Information Top Marking Y: Year (4=2014, 5=2015, ---) WW: Weekly (01-54) TYPICAL APPLICATION Page2-6

3 60, 3A STEP DOWN OLTAGE SWITCHING REGULATOR ABSOLUTE MAXIMUM RATINGS (Note 1) Characteristics Rating Maximum Supply oltage 63 ON/OFF Pin Input oltage / Feed Back Pin oltage -0.3 to IN Output oltage to Ground (Steady State) -1.0 Power Dissipation Thermal Resistance Junction to Ambient (θ JA ) Internally Limited ** 2 square inch of FR-4, double sided, 1oz. minimum copper 36 weight, is recommended Storage Temperature Range - 65 to 150 Maximum Junction Temperature Operating Temperature Range - 40 to 125 Minimum EDS Rating (Note 2) 2 Lead Temperature (Soldering, 10 sec) Units - /W k ELECTRICAL CHACRACTERISTICS (Specifications with standard type face are for TJ = 25 C, and those with bold face type apply over full Operating Temperature range. Unless otherwise specified, IN = 12 for 5.0 and Adj version, ILOAD = 500mA) Parameter Feedback Bias Oscillator Frequency Condition OUT =5 (Adjustable ersion Only) I b - 50 (Note 8) Symb ol Min Type Max Unit na f o khz Saturation oltage l OUT = 3A (Notes 4) SAT Max Duty Cycle (ON) (Note 5) DC % Limit Peak (Notes 4, 8) l CL A Output Leakage Output =0 (Notes 6, 7) l L 7.5 Output = (Notes 6, 7) ma Quiescent Standby Quiescent ON/OFF Pin Logic Input Level ON/OFF Pin Input (Note 6) l Q ma ON/OFF Pin = 5 (OFF), IN = 60 l STBY µa Low (ON) High (OFF) 1.0 IH IL LOGlC = 2.5 (OFF) I H µa LOGlC = 0.5 (ON) I L 0 10 Page3-6

4 60, 3A STEP DOWN OLTAGE SWITCHING REGULATOR Electrical Characteristics: SP3613-A (Specifications with standard type face are for T = 25, and those with bold face type apply over full Operating Temperature range) Parameter Condition Symbol Min Typ Max Unit Feedback oltage IN =12, I LOAD = 0.2A, OUT is set to < IN < 60, 0.2A < I LOAD < 3A, OUT is set to 5 FB Electrical Characteristics: SP (Specifications with standard type face are for T = 25, and those with bold face type apply over full Operating Temperature range) Parameter Condition Symbol Min Typ Max Unit IN = 12, I LOAD = 0.5A Output oltage OUT < IN < 60, 0.2A < I LOAD < 3A Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). Note 3: External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the SP3613 is used as shown in thee Figure 2 test circuit, system performance will be as shown in system parameters section of Electrical characteristics. Note 4: Output pin sourcing current. No diode, inductor or capacitor connected to output. Note 5: Feedback pin removed from output and connected to 0. Note 6: Feedback pin removed from output and connected to +12 to force the output transistor OFF. Note 7: IN =60. Note 8: The oscillator frequency reduces to approximately 11 khz in the event of an output short or an Over load which causes the regulated output voltage to drop approximately 40% from the nominal output voltage. This self protections feature lowers the average power dissipation of the IC by lowering the minimum duty cycle from 5% down to approximately Block Diagram Page4-6

5 60, 3A STEP DOWN OLTAGE SWITCHING REGULATOR Test Circuit and Layout Guidelines Careful layout is important with any switching regulators. Rapidly switching currents associated with wiring inductance generate voltage transients which can cause problems. To minimize inductance and ground loops, the lengths of the leads indicated by heavy lines in Figure 1&2 below should be kept as short as possible. Single point grounding (as indicated or ground plane construction should be used for best results. When using the Adjustable version, place the programming resistors as close as possible to SP3613, to keep the sensitive feedback wiring short. FB IN SP3613-xx OUT L1 100µH OUT IN Unregulatedd DC Input CIN 100µF GND SD D1 MBR360 COUT 680µ F L O A D Figure 1 Fixed Ouput otlage ersions C IN = 100µF, 75 Aluminum Electrolytic C OUT = 680µF, 25, Aluminum Electrolytic D1 = Schottky L1 = 100µH FB IN SP3613-A L1 100µH OUT OUT IN Unregulatedd DC Input CIN 100µF GND SD D1 MBR360 COUT 680µF R2 R1 L O A D Figure 2 Adjustable Ouput otlage ersions C IN = 100µF, 75 Aluminum Electrolytic C OUT = 680µF, 25, Aluminum Electrolytic D1 = Schottky L1 = 100µH OUT T = REF (1 + R2/R1) where REF = 1.23 and R1 is between 1K to 5K Page5-6

6 60, 3A STEP DOWN OLTAGE SWITCHING REGULATOR PACKAGE INFORMATION Package Outline Dimensions TO ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) (1.70) Typ ( ) ( ) Page6-6