TS2515 3A / 380KHz PWM Buck Converter SOP-8 Pin Definition: 1. N/C 8. SS 2. Vcc 7. EN 3. SW 6. NC 4. Vss 5. FB General Description TS2515 consists of step-down switching regulator with PWM control. These devise include a reference voltage source, oscillation circuit, error amplifier, internal PMOS and etc. TS2515 provides low-ripple power, high efficiency, and excellent transient characteristics. The PWM control circuit is able to the duty ratio linearly form 0 up to 100%. An enable function, an over current protect function and short circuit protect function are built inside, and when OCP or SCP happens, the operation frequency will be reduced. Also, an internal compensation block is built in to minimum external component count. With the addition of an internal P-channel Power MOS, a coil, capacitors, and a diode connected externally, these ICs can function as step-down switching regulators. They serve as ideal power supply units for portable devices when coupled with the SOP-8L package, providing such outstanding features as low current consumption. Since this converter can accommodate an input voltage up to 23V, it is also suitable for the operation via an AC adapter. Features ● ● ● ● ● ● ● ● Ordering Information Input Voltage: 4.5V~23V Output Voltage: 1.222V~Vcc Duty Ratio: 0%~100% PWM Control Oscillation Frequency: 380kHz typ. Soft-Start (SS), Current Limit (CL), Enable Function Thermal Shutdown Function Short Circuit Protect (SCP) Built-in Internal SW P-Channel MOSFET Part No. TS2515CS RL Package Packing SOP-8 2.5Kpcs / 13” Reel Application ● ● Simple High-efficiency Step down Regulator On-Card Switching Regulators Absolute Maximum Rating Parameter Symbol Rating Unit VCC Pin Voltage VCC Vss -0.3 to Vss +25 V Feedback Pin Voltage VFB Vss -0.3 to VCC V ON/OFF Pin Voltage VEN Vss -0.3 to VCC +0.3 V Switch Pin Voltage VSW Vss -0.3 to VCC +0.3 V Power Dissipation PD Internally limited mW Storage Temperature Range TST -40 to +150 ºC Operating Temperature Range TOP -20 to +125 ºC TJ -40 to +150 ºC Operating Supply Voltage VOP +4.5 to +23 V Thermal Resistance from Junction to case θJC 25 ℃/W Junction Temperature Range Thermal Resistance from Junction to ambient θJA 70 ℃/W 2 Note: θJA is measured with the PCB copper area (need connect to SW pins) of approximately 1 in (Multi-layer) 1/7 Version: A09 TS2515 3A / 380KHz PWM Buck Converter Electrical Specifications (VIN=12V, Ta=25oC unless otherwise noted) Characteristics Feedback Voltage Quiescent Current Feedback Bias Current Shutdown Supply Current Soft Stat pin current Current Limit Oscillation Frequency Maximum Duty Minimum Duty Symbol VFB Iq IFB EN Pin Pull High Current ISD ISS ICL FOSC DMAX DMIN VSH VSL IEN Internal P-MOS RDSON RDSON EN Pin Logic input threshold voltage Efficiency EFFI Thermal Shutdown Temp. TSD Conditions Min Typ Max Units 1.198 --- 1.222 3 0.1 1.246 5 0.5 V mA uA ---330 100 -1.5 --- 23 4.0 4.0 380 ----20 36 --430 -0 -0.7 36 uA uA A KHz % % VCC = 5V, VFB = 0V -- 90 140 mΩ VCC = 12V, VFB = 0V IOUT = 2A VCC = 12V, VOUT = 5V IOUT = 3A ----- 60 91 90 140 100 ---- mΩ IOUT =0.2A VFB =1.5V force driver off IOUT =0.2A VEN =0V SW pin VFB =1.0V VFB =1.5V High (regulator ON) Low (regulator OFF) VEN =0V V uA % ºC Block Diagram Pin Assignment Name FB EN SS Vcc Description Name Feedback pin Enable input, it is pull-high typically. Drive EN high or floating to turn on the regulator, driver it low to turn it off Soft-Start pin IC power supply pin 2/7 Description Vss GND pin SW Switch pin. Connect external inductor & diode here N/C No Connect Version: A09 TS2515 3A / 380KHz PWM Buck Converter Application Circuit Typical Circuit L1 recommend value (VIN=12V, IOUT=3A ) VOUT 1.8V 2.5V 3.3V 5V L1 Value 15uH 15uH 22uH 22uH Function Descriptions PWM Control The TS2515 consists of DC/DC converters that employ a pulse-width modulation (PWM) system. In converters of the TS2515, the pulse width varies in a range from 0 to 100%, according to the load current. The ripple voltage produced by the switching can easily be removed through a filter because the switching frequency remains constant. Therefore, these converters provide a low-ripple power over broad ranges of input voltage and load current. Setting the Output Voltage Application circuit item shows the basic application circuit with TS2515 adjustable output version. The external resistor sets the output voltage according to the following equation: Table 1: Resistor select for output voltage setting VOUT R2 R1 5V 5.6K 1.8K 3.3V 5.6K 3.3K 2.5V 1.25K 1.2K 1.8V 2.2K 4.7K 1.5V 1.1K 4.7K 3/7 Version: A09 TS2515 3A / 380KHz PWM Buck Converter Function Descriptions (Continue) Input Capacitor Selection For most designs, the operating inductor range is 15µH to 22µH. The inductor value can be derived from the following equation: Where is inductor Ripple Current. Large value inductors lower ripple current and small value inductors result in high ripple currents. Choose inductor ripple current approximately 15% of the maximum load current 3A, ∆IL=0.45A. The DC current rating of the inductor should be at least equal to the maximum load current plus half the ripple current to prevent core saturation (3A+0.45A). Inductor Selection The input current to the step-down converter is discontinuous, and so a capacitor is required to supply the AC current to the step-down converter while maintaining the DC input voltage. A low-ESR capacitor is required to keep the noise at the IC to a minimum. The low-ESR electrolytic capacitor may also suffice. The input capacitor value should be greater than 470µF. However since it absorbs the input switching current it requires an adequate ripple current rating. Its RMS current rating should be greater than approximately 1/2 of the DC load current. For insuring stable operation CIN should be placed as close to the IC as possible. Alternately a smaller high quality ceramic 0.1uF capacitor may be placed closer to the IC and a larger capacitor placed further away. If using this technique, it is recommended that the larger capacitor be a electrolytic type. Output Capacitor The output capacitor is required to maintain the DC output voltage. Low ESR capacitors are preferred to keep the output voltage ripple low. The characteristics of the output capacitor also affect the stability of the regulation control system. The low-ESR electrolytic capacitors are recommended. The output capacitor value should be greater than 470µF. 4/7 Version: A09 TS2515 3A / 380KHz PWM Buck Converter Electrical Characteristics Curve Figure 1. Quiescent Current vs. Input Voltage Figure 2.Standby Current vs. Input Voltage Figure 3. Output Voltage vs. Output Current Figure 4. Frequency vs. Temperature Figure 10. Efficiency vs. Output Current 5/7 Version: A09 TS2515 3A / 380KHz PWM Buck Converter SOP-8 Mechanical Drawing DIM A B C D F G K M P R SOP-8 DIMENSION MILLIMETERS INCHES MIN MAX MIN MAX. 4.80 5.00 0.189 0.196 3.80 4.00 0.150 0.157 1.35 1.75 0.054 0.068 0.35 0.49 0.014 0.019 0.40 1.25 0.016 0.049 1.27BSC 0.05BSC 0.10 0.25 0.004 0.009 0º 7º 0º 7º 5.80 6.20 0.229 0.244 0.25 0.50 0.010 0.019 Marking Diagram Y = Year Code M = Month Code (A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep, J=Oct, K=Nov, L=Dec) L = Lot Code 6/7 Version: A09 TS2515 3A / 380KHz PWM Buck Converter Notice Specifications of the products displayed herein are subject to change without notice. TSC or anyone on its behalf, assumes no responsibility or liability for any errors or inaccuracies. Information contained herein is intended to provide a product description only. No license, express or implied, to any intellectual property rights is granted by this document. Except as provided in TSC’s terms and conditions of sale for such products, TSC assumes no liability whatsoever, and disclaims any express or implied warranty, relating to sale and/or use of TSC products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright, or other intellectual property right. The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications. Customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify TSC for any damages resulting from such improper use or sale. 7/7 Version: A09