S5J2596M 150 KHz, 3A PWM Elektronische Bauelemente Step-Down DC/DC Converter Description The S5J2596M series of regulators are monolithic integrated circuit that provides all active functions for a step-down (buck) switching regulator, capable of driving 3A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V,5V,12V and an adjustable output version. The S5J2596M series ioerate at a switching frequency of 150 KHz; thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Available in standard 5-lead TO-252 package. Other feature include a guaranteed ± 4% to tolerance on output voltage under specified input voltages and output load conditions. The 150KHz ±15% is on the oscillator frequency. External shutdown is included, featuring 80uA(Typ.) standby current. The output switch includes cycle-by cycle current limiting, as well as thermal shutdown for full protection under fault conditions. Features * Uses Readily Available Standard Inductors * Operating Voltage Can Be Up To 22V * Thermal Shutdown And Current Limit Protection * 3.3V,5V,12V and adjustable Output Versions * TTL Shutdown Capability * Built-in TTL On/Off Control * Guaranteed 3A Output Current * 150 KHz Fixed Frequency Internal Oscillator REF. A B C D P S Millimeter Min. Max. 6.35 6.73 5.21 5.46 9.40 10.20 2.40 3.00 1.27 REF. 0.50 0.80 REF. G H J K L M Millimeter Min. Max. 0.45 0.60 2.20 2.40 0.46 0.58 0 0.15 0.90 1.50 5.40 5.59 Applications * Positive To Negative Converter * High-Effciency Step-Down Regulator * One-ch Switching Regulators Simple Block Diagram http://www.SeCoSGmbH.com/ 01-Jun-2002 Rev. A Any changing of specification will not be informed individual Page 1 of 6 S5J2596M 150 KHz, 3A PWM Elektronische Bauelemente Pin Function Pin Name Step-Down DC/DC Converter Pin# GND VIN 1 Output 2 Ground Feedback(FB) NC ON/OFF(SD) 3 4 5 Function Description This is the positive input supply for the IC switching regulator. A suitable input bypass capacitor must be present at this pin to minimize voltage transients and to supply the switching current must be present at this pin to minimize voltage transients and to supply the switching current needed by regulator. 0.5V, V SAT) and approximately - 0.5V, Internal voltage at this ispinconnected switches from between (+V Typicallyswitch. a largeThe storage capacitor thiscoupling pin IN to -ground to insure that the . To minimize to sensitive circuitry, the input PC with a duty cycle of approximately VOUT/V IN. To minimize coupling to sensitive circuitry, the PC 1.3V board copper area connected to this pin should be keep to a minimum. Circuit ground or open= output enable. Senses the regulated output voltage to complete the feedback loop . tage does not sag below the minimum dropout voltage during the load Allows the switching regulator circuit to be shutdownV using logic level signals. Thus the totalto Vout in order fordrop the device Allows the switching regulator circuit to be shutdownhigher using than logic level signals. Thus drop the total threshold voltage of input supply current to approximately 150 A. Pulling this pin below a threshold voltage of of approximately 1.3V turns the regulator on, and pulling this pin above 1.3V (up to a maximum 18V) shuts the regulator down. If this shutdown feature is not needed, ON/OFF pin can be wired to of 18V) shuts the regulator down. If this shutdown feature is not needed, ON/OFF pin can be wired to the ground pin. Absolute Maximum Ratings Parameter Symbol VCC VSD VFB VOUT PD TST TOP VOP Supply Voltage ON/OFF Pin Input Voltage Feedback Pin Voltage Output Voltage to ground Power Dissipation Storage Temperature Operating temperature Operating Voltage Ratings 24 -0.3 ~ +18 -0.3 ~ +18 -1 Internally Limited -65 ~ +150 -40 ~ +125 +4.5 ~ +22 Unit V V V V W V S5J2596M Electrical Characteristics Specifications in boldface type are for full operating temperature range. The other type are for TJ=25 Parameter Output Feedback Symbol VFB Efficiency Conditions 5 VIN 22V, 0.2A ILOAD 3A VOUT=3V VIN=12V, ILOAD=3A, VOUT=3V . Min Typ Max Unit 1.193/1.180 1.230 1.267/1.280 V 74 % S5J2596M-33 Electrical Characteristics Specifications in boldface type are for full operating temperature range. The other type are for TJ=25 Parameter Output Feedback Symbol VFB Efficiency Conditions 5.5V VIN 22V 0.2A ILOAD 3A VIN=12V, ILOAD=3A . Min Typ Max Unit 3.168/3.135 3.3 3.432/3.465 V 75 % S5J2596M-50 Electrical Characteristics Specifications in boldface type are for full operating temperature range. The other type are for TJ=25 Parameter Output Feedback Symbol VFB Efficiency Conditions 8V VIN 22V 0.2A ILOAD 3A VIN=12V, ILOAD=3A . Min Typ Max Unit 4.80/4.75 5.0 5.20/5.25 V 80 % S5J2596M-12 Electrical Characteristics Specifications in boldface type are for full operating temperature range. The other type are for TJ=25 Parameter Output Feedback Efficiency http://www.SeCoSGmbH.com/ 01-Jun-2002 Rev. A Symbol VFB Conditions 15V VIN 22V 0.2A ILOAD 3A VIN=16V, ILOAD=3A . Min Typ Max Unit 11.52/11.40 12 12.48/12.60 V 89 % Any changing of specification will not be informed individual Page 2 of 6 S5J2596M 150 KHz, 3A PWM Elektronische Bauelemente Step-Down DC/DC Converter All Output Voltage Version Electrical Characteristics Specifications in boldface type are for full operating temperature range. The other type are for TJ=25 Parameter Feedback bias current Oscillator frequency Symbol IFB Conditions VFB=1.3V (adjustable version only) FOSC . Min 127/110 Typ -10 150 Max -50/-100 173/173 Unit nA kHz Oscillator frequency of short circuit protect FSCP When current limit occurred and VFB<0.5V, TA=25 . 5 15 25 kHz Saturation voltage VSAT ILOAD=3A No outside circuit VFB=0V force drive on - 1.4 1.6/1.7 V - 100 0 - % 3.6 4.5 5.5/6.5 A - - -200 uA - 10 mA mA 2.0 -5 5 - Max. duty cycle (ON) Max. duty cycle (OFF) DC Current limit ICL Output leakage current IL Quiescent current IQ VFB=0V force drive on VFB=12V force drive off Peak current No outside circuit VFB=0V force drive on Output=0V, No outside circuit VFB=12V force drive off Output=-1V, VIN=22V VFB=12V force drive off ON/OFF pin logic input VIL Low (Regulator ON) Threshold Voltage ON/OFF pin Logic input current VIH High (Regulator OFF) IH VLOGIC=2.5V ( Regulator OFF) - IL VLOGIC=0.5V ( Regulator ON) - -0.1 -1 - 150 200 - 10 - - 50 - ON/OFF pin input current Standby quiescent current ISTBY ON/OFF pin=5V, VIN=12V JC Thermal Resistance JA Junction to Case Junction to Ambient with copper area of approximately 2 cm2 - 0.6 - V -0.01 uA uA /W Unless otherwise specified, VIN=12V for 3.3V, 5V, adjustable version and VIN=18V for the 12V version. ILOAD=0.5A Function Description The TO-252-5L surface mount package tab is designed to be soldering to the copper on a printed circuit board. The copper and the board are the heat sink for this package and the other heat producing components, such as the catch diode and inductor. The PC board copper 2 area that the package is soldered to should be at least 0.8 in and ideally should have 2 or more square inches of 2 oz. Additional copper 2 area improve the thermal characteristics, but with copper areas greater than approximately 6 in , only small improvements in heat dissipation are realized. If further thermal improvements are needed, double sided, multi-layer PC board with large copper areas and/or airflow will be recommended. The S5J2596M junction temperature rises above ambient temperature with a 3A load and different input and output voltages. The data was taken with the circuit operating as a buck-switching regulator with all components mounted on a PC board to simulate the junction temperature under actual operating conditions. This curve can be used for a quick check for the approximate junction temperature for various conditions, but be aware that there are many factors that can affect the junction temperature. When load current higher than 3A are used, double sided or multi-layer PC boards with large copper areas and/or airflow might be needed, especially for high ambient temperatures and high output voltages. For the best thermal performance, wide copper traces and generous amounts of printed circuit board copper should be used in the board layout. (One exception to this is the output (switch) 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 rise numbers are all approximate, and there are many factors will affect these numbers. 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 double-sided, 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 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. h tp://www.SeCoSGmbH.com/ 01-Jun-2002 Rev. A Any changing of specification will not be informed individual Page 3 of 6 S5J2596M 150 KHz, 3A PWM Elektronische Bauelemente Step-Down DC/DC Converter Typical Application Circuit (1)Fixed Type Circuit S5E2596M S5E2596M S5E2596M S5J2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M S5E2596M -33 -33 -33 -33 -33 -33 BMKFE -33 -33 -33 -33 -33 BMKFE -33 BMKFE -33 BMKFE BMKFE -33 -33 -33 -33 (2)Adjustable Type Circuit BMKFE S5J 2596M BMKFE S5E2596M BMKFE BMKFE BMKFE BMKFE BMKFE BMKFE -33 (3)Delay Start Circuit BMKFE S5J2596M BMKFE BMKFE BMKFE BMKFE BMKFE BMKFE BMKFE BMKFE BMKFE BMKFE 5 http://www.SeCoSGmbH.com/ 01-Jun-2002 Rev. A 3 Any changing of specification will not be informed individual Page 4 of 6 S5J2596M Elektronische Bauelemente 150 KHz, 3A PWM Step-Down DC/DC Converter Typical Performance Characteristics http://www.SeCoSGmbH.com/ 01-Jun-2002 Rev. A Any changing of specification will not be informed individual Page 5 of 6 S5J2596M 150 KHz, 3A PWM Elektronische Bauelemente GND Step-Down DC/DC Converter Description Typically a large storage capacitor is connected from this pin to ground to insure that the input 1.3V or open= output enable. NC http://www.SeCoSGmbH.com/ 01-Jun-2002 Rev. A tage does not sag below the minimum dropout voltage during the load V higher than Vout in order for the device to Any changing of specification will not be informed individual Page 6 of 6