5.0A, 300kHz, Step-down Switching Regulator

Transcription

1 FEATURES 3.3, 5,, and adjustable output versions Adjustable version output voltage range, 1.23 to 37 ± 3% max over line and load conditions Guaranteed 5A output load current Input voltage range up to 4 Requires only 4 external components 3kHz ±15% fixed frequency internal oscillator Excellent line and load regulation specifications Low power standby mode, I Q typically 8uA Thermal shutdown and current limit protection TO-263 PKG TO-22 PKG APPLICATION Simple high-efficiency step-down regulator On-card switching regulators Positive to negative converter DESCRIPTION Ordering Information Device R-X.X T-X.X X.X = oltage = 3.3, 5., 12, ADJ PKG TO-263 5L TO-22 5L The series of regulators are monolithic integrated circuits that provide all the active functions for a step-down switching regulator, capable of driving a 5A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3, 5, and an adjustable output version. Requiring a minimum number of external components, these regulators are simple to use. The series operates at a switching frequency of 3kHz. Available in standard 5-lead TO-263 and TO-22 packages. Other features include a guaranteed ±3% tolerance on output voltage under specified input voltage and output load conditions, and ± 15% on the oscillator frequency. External shutdown is included, featuring typically 8uA standby current. Self protection features include a current limit for output switch and an over temperature shutdown for complete protection under fault conditions. The over temperature shutdown level is about 145 with 5 hysteresis. Absolute Maximum Ratings (T A = 25 o C) (Note 1) Characteristic Symbol alue Unit Maximum Input Supply oltage I 45 ON/OFF Pin Input oltage IN Feedback Pin oltage oltage to Ground O -1 Power Dissipation P D Internally limited W Storage Temperature Range T stg -65 to +15 Operating Temperature Range T J -4 T J +125 ESD Susceptibility (Human Body Model) ESD 2 k Operating Supply oltage IN 4.5 to 45 Note 1. Absolute Maximum Rating 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. June 213 er HTC o C o C

2 Ordering Information OUT Package Order No. Description Package Marking Supplied As ADJ TO-263 5L R-ADJ-5L 5A, 3kHz -ADJ Reel TO-22 5L T-ADJ-5L 5A, 3kHz -ADJ Tube 3.3 TO-263 5L R-3.3-5L 5A, 3kHz -3.3 Reel TO-22 5L T-3.3-5L 5A, 3kHz -3.3 Tube 5. TO-263 5L R-5.-5L 5A, 3kHz -5. Reel TO-22 5L T-5.-5L 5A, 3kHz -5. Tube TO-263 5L R-12-5L 5A, 3kHz -12 Reel TO-22 5L T-12-5L 5A, 3kHz -12 Tube LM 151B R L Lead Count : 5L oltage : ADJ / 3.3 / 5. / Package Type Root Name R T : TO-263 : TO-22 Product Code PIN CONFIGURATION SD GND OUTPUT SD GND OUTPUT TO-263 5L TO-22 5L PIN DESCRIPTION Pin No. Name TO-263 / TO-22 5 LEAD Function 1 IN Operating Input oltage 2 OUTPUT Switching oltage 3 GND Ground 4 oltage Feedback Control 5 SD ON/OFF Shutdown June 213 er HTC

3 Electrical Characteristics Unless otherwise specified, T J =25 IN = for the 3.3, 5, and Adjustable version and IN = 24 for the version. I LOAD = 5mA. Characteristic Symb ol Test Condition Min Typ Max Unit -ADJ OUT = 3, I LOAD = 5A 73 Efficiency -3.3 IN =, I LOAD = 5A 73-5 IN =, I LOAD = 5A 8 % oltage OUT -12 IN = 25, I LOAD = 5A Feedback oltage -ADJ 4.75 IN 4 7 IN 4 15 IN IN OUT programmed for 3 Oscillator Frequency f O khz Feedback Bias Current I D -ADJ; = na Saturation oltage SAT I OUT = 5A, (Note 2, 3) 1.4 Max Duty Cycle (ON) Max Duty Cycle (OFF) DC (Note 3) 1 (Note 4) % Current Limit I CL Peak Current, (Note 2, 3) 6.5 A Leakage Current I L = (Note 2, 4) 5 A = -1, IN=4 2 3 ma Quiescent Current I Q (Note 4) ma Standby Quiescent Current I STBY ON/OFF pin = 5(OFF), IN = A ON/OFF Pin Logic Input Threshold voltage ON/OFF Pin Logic Input current 1.3 IH Low (Regulator ON).6 IL High (Regulator OFF) 2. I H LOGIC = 2.5 (regulator OFF) 5 15 I L LOGIC =.5 (regulator ON) 5 ua Note 2. No elements connected to output pin Note 3. Feedback pin removed from output and connected to to force the output transistor switch ON. Note 4. Feedback pin removed from output and connected to for the 3.3, 5, and the ADJ version, and 15 for the version. To force the output transistor switch OFF June 213 er HTC

4 ON/OFF Pin Logic Input Current [ua] Efficiency [%] Standby Quiescent Current [ua] Quiescent Current [ma] 5.A, 3kHz, Step-down Switching Regulator TYPICAL APPLICATION - Fixed Application Circuit - Adjustable Application Circuit Unregulated DC Input CIN 68uF Feedback GND 3 ON/OFF 5 D1 L1 15uH COUT 22uF 5 Regulated 5A Load Unregulated DC Input CIN 68uF Feedback 1 4 -ADJ 2 GND 3 ON/OFF 5 D1 L1 15uH 5 COUT 22uF Regulated 5A Load O UT = ( +1) = ( +1) TYPICAL OPERATING CHARACTERISTICS in=24, out= in=24, out= Current [A] T.B.D June 213 er HTC

5 APPLICATION INFORMAION T.B.D June 213 er HTC