STD2596. PWM Control Step-Down DC/DC Converter. 150KHz, 3A PWM Buck DC/DC Converter FEATURE DESCRIPTION APPLICATIONS PIN CONFIGURATION

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1 DESCRIPTION The STD2596 series of regulators are monolithic integrated circuits that provide all the 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 voltage of 5V and adjustable output version. The STD2596 operates at a switching frequency of 5KHz thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Other features include a guaranteed ±3% tolerance on output voltage under specified input voltage and output load conditions, and ±5% on the oscillator frequency. External shutdown is included, featuring typically ua standby current. STD2596-XXD-TRG ROHS Compliant This is Halogen Free PIN CONFIGURATION Metal Tab STD2596 5KHz, 3A PWM Buck DC/DC Converter FEATURE 5V and adjustable output versions Adjustable version output voltage range.23v to 36V Input voltage range up to 38V Guaranteed 3A output current 5KHz fixed frequency internal oscillator Built-in thermal shutdown and current limit protection APPLICATIONS Fixed voltage power supply for LCD monitor and LCD TV On-Card switching regulation Simple high efficiency Step-down regulator PWM Control Step-Down DC/DC Converter FB EN TO263-5L Top View PART NUMBER INFORMATION STD XX D TR G a b c d e f a : Company name. b : Product Serial number. c : Voltage Code. XX 5 : 5.V, ADJ : ADJ d : Package code. e : Handling code. f : Green produce code.

2 ORDERING INFORMATION Part Number Package Code Voltage Shipping STD2596-XXD-TRG D :TO-263-5L 5. ADJ 8 Pcs/Reel Year Code : ~ 9, 2 : Week Code : A(~2) ~ Z(53~5) TO-263-5L : Only available in tape and reel packaging. BLOCK DIAGRAM ABSOLUTE MAXIMUM RATINGS (TA = 25 Unless otherwise noted ) Symbol Parameter Maximum Unit PD Power Dissipation Internally Limited W Maximum Supply Voltage V EN EN Pin Input Voltage -.3V < V < + V θjt Thermal resistance junction to Case 3. C /W θja Thermal resistance junction to Ambient 36 C/W TJ Operating Junction Temperature Range -~+25 C TSTG Storage Temperature Range -65~+5 C ESD Minimum EDS Rating (C=pF, R=.5KΩ 2 KV TLEAD Lead Soldering Temperature (Soldering, sec) 26 C Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of the specified terminal. θja : Thermal Resistance-Junction to Ambient, Junction Temperature Calculation: TJ = TA + (PD θja) The θja numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. θjt : Thermal Resistance-Junction to Ambient, 2

3 ELECTRICAL CHARACTERISTICS(TJ = 25 Unless otherwise noted ) STD2596 Unless otherwise specified, these specifications apply = 2V for 5.V options, and = 2V for Adj option, and the operating ambient temperatures TA = 25 C Symbol Parameter Test Conditions Min Typ Max Unit 5.V V FB ADJ Output Voltage (Note ) 7V 38V.2A IOUT 3A.5V 38V.2A IOUT 3A = 3V V η 5.V = 2V, ILOAD = 3A Efficiency ADJ = 2V, ILOAD = 3A, = 3V % IB Feeback Bias Current VFB=.3V (Adiustable Version Only) - 5 na VSAT Saturation Voltage Iout=3A, (Note, 2) -.6. V fo Oscillator Frequency (Note 2) KHz DC Duty Cycle (ON) (Note 3) - - % DC Duty Cycle (OFF) (Note ) - - % IL Output Leakage Current Output=V, (Note 3,,) - - μa Output=-.9V ma IQ Quiescent Current (Note ) ma ISTBY Standby Current EN Pin=5V(OFF) - 2 μa VIH Low (ON) VIL High (OFF) EN Pin Input Level IH VLEVEL= 2.5V (OFF) IL VLEVEL=.5V (ON) Note : No diode, inductor or capacitor connected to output pin. Note 2: The switching frequency is reduced when the second stage current limit is activated. Note 3: Feedback pin removed from output and connected to V to force the output transistor switch ON. Note : Feedback pin removed from output and connected to 2V for the 5V, and the ADJ. version. V μa RECOMMENDED OPERATING CONDITIONS Symbol Parameter Operating Conditions Min Typ Max Unit V IN Input Voltage V I PC Peak Current A I OUT Maximum Load Current A T J Junction Temperature

4 TYPICAL APPLICATIONS Adjustable Output Voltage L CIN EN STD2596-ADJ FB D Schottky Diodes R R2 COUT =.23x (+ R R2 ) CIN = μf, Aluminum Electrolytic COUT = 22μF, 25V, Aluminum Electrolytic D = Schottky, 5A/V L = 33μH Figure 2 Fixed Voltage Regulator: L CIN EN STD FB D Schottky Diodes COUT CIN = μf, Aluminum Electrolytic COUT = 22μF, 25V, Aluminum Electrolytic D = Schottky, 5A/V L = 33μH

5 TYPICAL CHARACTERISTICS (25 Unless Note) Saturation Voltage (V) Switch Stauration Voltage Vin=2V Tj=- C Tj=25 C Tj=25 C Switch Current (A) Switch Current Limit (A) Switch Current Limit Vin=2V Vout=5V -5 5 Junction Temperature( C) Input-Output Differential L=33μH R IND =. V OUT =V REG =5mV ILOAD=A Dropout Voltage ILOAD=3A Junction Temperature ( C) Switch Current (ma) Operating Quiescent Current 2.5V < < 38V, I SWITCH = 2 ON OFF Junction Temperature ( C) Minimum Operating Supply Voltage Shutdown Quiescent Current Supply Voltage (v) 5 V OUT =.23V, I LOAD = 2mA Junction Temperature( C) Current (ua) V EN = 5V Tj=25 C Tj=25 C 2 3 Supply Voltage (V) 5

6 TYPICAL CHARACTERISTICS (25 Unless Note) SD pin Current (Sinking) Switching Frequency Current (ua) V IN = 38V T J = - C and 25 C Frequency (KHz) SD Pin Voltage (V) TJunction Temperature( C) 6

7 TO263-5L PACKAGE DIMENSIONS Symbol Dimensions In Millimeters Dimensions In Inches Min. Max. Min. Max. A A A b b c c c2.27 BSC.5 BSC D D 8. REF.35 REF D2 7. REF.276 REF E E E2 5.8 BSC.228 REF e.7 BSC.67 BSC L L.65 BSC.65 BSC θ 8 8 7