TS2596S Taiwan Semiconductor 2A, 24V, 150kHz Step-Down DC-DC Converter DESCRIPTION FEATURES TS2596S Series are step-down switching regulators ● Output Voltage: 5V & Adjustable version with all required active functions. It is capable of driving ● Adjustable Output Voltage 1.23V~19.5V ±4% 2A load with excellent line and load regulations. These ● 150kHz ±15% fixed switching frequency devices are available in fixed output voltages of 5V, ● Voltage Mode Non-synchronous PWM control and an adjustable output version. TS2596S series ● Thermal Shutdown and Current Limit Protection ● ON/OFF Shutdown Control Input ● Soft-Start (SS) Function ● Short Circuit Protect (SCP) ● Operating Voltage Can be up to 24V ● Output Load Current 2A ● Low Power Standby Mode operates at a switching frequency of 150kHz thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. It substantially not only reduces the area of board size but also the size of heat sink, and in some cases no heat sink is required. The ±4% tolerance on output voltage within specified input voltages and output load conditions is guaranteed. Also, the APPLICATION oscillator frequency accuracy is within ±10%. External shutdown is included. Featuring 70μA (typical) standby current. The output switch includes cycle-by-cycle ● Simple High-efficiency Step down Regulator ● On-Card Switching Regulators current limiting, as well as thermal shutdown for full protection under fault conditions. SOP-8 Pin Definition: 1. Input 2. SW Output 3. Feedback 4. Enable 8. GND 7. GND 6. GND 5. GND Notes: MSL 3 (Moisture Sensitivity Level) per J-STD-020 ABSOLUTE MAXIMUM RATINGS (TA = 25°C unless otherwise specified) (Note 1) PARAMETER SYMBOL LIMIT UNIT Supply Voltage VCC +28 V Operating Voltage Range VOP +4.5 to +24 V SW, EN Pin Input Voltage VSW , VEN -0.3 to VCC V Feedback Pin Voltage VFB -0.3 to VCC V Power Dissipation PD Internally Limited W VOUT -1 Output Voltage to Ground Storage Temperature Range THERMAL PERFORMANCE -65 to +150 TOP -40 to +125 o SYMBOL RθJC RθJA LIMIT 15 70 TST Operating Temperature Range V o C C (Note 3) PARAMETER Thermal Resistance Junction to Case Thermal Resistance Junction to Ambient 1 UNIT °C/W °C/W Version: C1602 TS2596S Taiwan Semiconductor ELECTRICAL SPECIFICATIONS (TA = 25°C unless otherwise specified) PARAMETER SYMBOL Output Feedback ADJ Efficiency VFB η Output Feedback 5V VFB CONDITION MIN 4.5V≤ VIN ≤24V 1.193 0.2A≤ ILOAD ≤2A 1.180 VIN =12V, ILOAD =2A 76 7V≤ VIN ≤24V 4..80 0.2A≤ ILOAD ≤2A 4.75 TYP 1.23 -5 MAX 1.267 1.280 -5.20 5.25 UNIT V % V Efficiency η VIN =12V, ILOAD =2A 84 -- -- % Feedback Bias Current IFB VFB =1.3V (Adj version only) -- -10 -100 nA 127 150 173 kHz -- 3 -- ms 2.4 -- -- A -- 60 -- kHz -- 1.15 1.50 V Oscillator Frequency FOSC Soft-Start Time TSS Current Limit ICL Oscillator Frequency of Short Circuit Protect Saturation Voltage FSCP VSAT Rising edge of EN on to ICL Pear Current, no outside circuit VFB =0V force driver on When current limit occurred and o VFB <0.5V, TA = 25 C IOUT=2A, No outside circuit VFB =0V force driver on ON/OFF Pin Logic Input VIL Low (regulator ON) Threshold Voltage VIH High (regulator OFF) -2.0 1.3 0.6 -- ON/OFF Pin Logic Input IL VLOGIC =2.5V (OFF) -- -0.1 -0.5 Current IH VLOGIC =0.5V (ON) -- -- -0.01 VFB =0V force driver on -- 100 -- VFB =12V force driver off -- 0 -- VFB =12V force driver off -- 4 8 ON/OFF pin=5V -- VIN =24V -- Maximum Duty Cycle (ON) Maximum Duty Cycle (OFF) Quiescent Current IQ Standby Quiescent Current SW Pin Leakage Current DC SW = 0 ISTBY No outside circuit, ISWL SW = -1 VFB =12V force driver off VIN =24V 45 100 100 V µA % mA µA -- -- -200 µA -- -5 -- mA Note: 1. Stresses listed as the above “Absolute Maximum Ratings” may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. 2. Devices are ESD sensitive. Handing precaution recommended. 3. Thermal Resistance is specified with the component mounted on a low effective thermal conductivity test board in free air at TA=25°C. ORDERING INFORMATION OUTPUT VOLTAGE PART NO. PACKAGE PACKING Adjustable TS2596SCS RLG SOP-8 2,500pcs / 13”Reel 5V TS2596SCS50 RLG SOP-8 2,500pcs / 13”Reel 2 Version: C1602 TS2596S Taiwan Semiconductor FUNCTION BLOCK TYPICAL APPLICATION CIRCUIT Adjustable Output Voltage Version Resistor select for output voltage setting VOUT R1 R2 4.7K 1.5K 5V 5.6K 1.8K 2.5K 1.5K 3.3V 3.0K 1.8K 2.5V 1.8K 1.8K 1.8V 0.82K 1.8K Adjustable Output Voltage Version with Delayed Startup Inverting -5V Regulator with Delayed Startup 3 Version: C1602 TS2596S Taiwan Semiconductor APPLICATION INFORMATION Pin Function Descriptions VCC This is the positive input supply for the IC switching regulator. A suitable input bypass capacitor must be presented at this pin to minimize voltage transients and to supply the switching currents needed by the regulator. Ground Circuit ground SW Output Internal switch. The voltage at this pin switches between (+VCC – VSAT) and approximately – 0.5V, with a duty cycle of approximately VOUT / VCC. To minimize coupling to sensitive circuitry, the PC board copper area connected to this pin should be minimized. Feedback Sense the regulated output voltage to complete the feedback loop. Enable Allow the switching regulator circuit to be shutdown using logic level signals, thus dropping the total input supply current to approximately is 100µA. Pulling this pin below a threshold voltage of approximately 1.3V turns the regulator on, and pulling this pin above 1.3V (up to a maximum of VCC) shuts the regulator down. If this shutdown feature is not needed, the EN pin can be wired to the ground pin. Thermal Considerations The SOP-8 package needs a heat sink under most conditions. The size of the heat sink depends on the input voltage, the output voltage, the load current and the ambient temperature. The TS2596S junction temperature rises above ambient temperature for a 2A load and different input and output voltages. The data for these curves was taken with the TS2596S (SOP-8) package operating as a buck-switching regulator in an ambient temperature of 25ºC (still air). These temperature increments are all approximate and are affected by many factors. A higher ambient temperature requires more heat sinker. For the best thermal performance, wide copper traces and generous amounts of printed circuit board copper (need connect to the Ground pin) should be used in the board layout, (one exception is the SW pin, which should not have large areas of copper.) Large areas of copper provide the best transfer of heat (lower thermal resistance) to the surrounding air, and moving air lowers the thermal resistance even further. Package thermal resistance and junction temperature increments are all approximate. The increments are affected by a lot of factors. Some of these factors include board size, shape, thickness, position, location, and even board temperature. Other factors are, trace width, total printed circuit copper area, copper thickness, single or doublesided, multi-layer board and the amount of solder on the board. The effectiveness of the PC board to dissipate heat also depends on the size, quantity and spacing of other components on the board, as well as whether the surrounding air is still or moving. Furthermore, some of these components such as the catch diode will add heat to the PC board and the heat can vary as the input voltage changes. For the inductor, depending on the physical size, type of core material and the DC resistance, it could either act as a heat sink taking heat away from the board, or it could add heat to the board. 4 Version: C1602 TS2596S Taiwan Semiconductor CHARACTERISTICS CURVES (TC = 25°C unless otherwise noted) Figure 1 – VOUT vs. VIN Figure 2 – Quiescent Current vs. VIN Figure 3 – Frequency vs. VIN Figure 4 – Frequency vs. Temperature Figure 5 – Feedback Voltage vs. Temperature Figure 6 – Quiescent Current vs. Temperature 5 Version: C1602 TS2596S Taiwan Semiconductor CHARACTERISTICS CURVES (TC = 25°C unless otherwise noted) Figure 7 – Threshold Voltage vs. Temperature Figure 8 – ON/OFF Current vs. Voltage Figure 9 – Output Voltage vs. Temperature Figure 10 – Feedback Current vs. Temperature Figure 11 – Efficiency (VIN=12V, VOUT=3.3V) Figure 12 – Efficiency (VIN=12V, VOUT=5V) 6 Version: C1602 TS2596S Taiwan Semiconductor PACKAGE OUTLINE DIMENSIONS (Unit: Millimeters) SOP-8 SUGGESTED PAD LAYOUT (Unit: Millimeters) MARKING DIAGRAM XX Y M L = Output Voltage 50 =5.0V Blank = Adjustable = Year Code = Month Code for Halogen Free Product O =Jan P =Feb Q =Mar R =Apr S =May T =Jun U =Jul V =Aug W =Sep X =Oct Y =Nov Z =Dec = Lot Code 7 Version: C1602 TS2596S Taiwan Semiconductor 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. 8 Version: C1602