L6910ATR STMicroelectronics

L6910 L6910A ADJUSTABLE STEP DOWN CONTROLLER WITH SYNCHRONOUS RECTIFICATION Figure 1. Packages 1 FEATURES OPERATING SUPPLY VOLTAGE FROM 5V TO 12V BUSES UP TO 1.3A GATE CURRENT CAPABILITY ADJUSTABLE OUTPUT VOLTAGE HTSSOP16 (Exposed Pad) SO-16 (Narrow) N-INVERTING E/A INPUT AVAILABLE 0.9V 1.5% VOLTAGE REFERENCE Table 1. Order Codes VOLTAGE MODE PWM CONTROL Part Number Package VERY FAST LOAD TRANSIENT RESPONSE L6910 SO-16 0% TO 100% DUTY CYCLE POWER GOOD OUTPUT L6910TR SO-16 in Tape & Reel OVERVOLTAGE PROTECTION L6910A HTSSOP16 HICCUP OVERCURRENT PROTECTION L6910ATR HTSSOP16 in Tape & Reel 200kHz INTERNAL OSCILLATOR OSCILLATOR EXTERNALLY ADJUSTABLE dc-dc conversion from 3.3V, 5V and 12V buses. FROM 50kHz TO 1MHz The output voltage is adjustable down to 0.9V SOFT START AND INHIBIT higher voltages can be obtained with an external PACKAGES: SO-16 & HTSSOP16 voltage divider. High peak current gate drivers provide for fast switch- 2 APPLICATIONS ing to the external power section, and the output SUPPLY FOR MEMORIES AND TERMI- current can be in excess of 20A. NATIONS The device assures protections against load overcur- COMPUTER ADD-ON CARDS rent and overvoltage. An internal crowbar is also pro- LOW VOLTAGE DISTRIBUTED DC-DC vided turning on the low side mosfet as long as the MAG-AMP REPLACEMENT over-voltage is detected. In case of over-current de- tection, the soft start capacitor is discharged and the 3 DESCRIPTION system works in HICCUP mode. The device is a pwm controller for high performance Figure 2. Block Diagram V 5V to 12V in VCC OCSET PGOOD MONITOR PROTECTION BOOT VREF & REF SS UGATE V OSC BOOT O OSC R T PWM E/A - LGATE EAREF + + - PGND GND VFB COMP D03IN1509 Rev. 9 May 2005 1/29 300KL6910 - L6910A Table 2. Absolute Maximum Ratings Symbol Parameter Value Unit Vcc Vcc to GND, PGND 15 V V - Boot Voltage 15 V BOOT V PHASE V - 15 V HGATE V PHASE OCSET, LGATE, PHASE -0.3 to Vcc+0.3 V SS, FB, PGOOD, VREF, EAREF, RT 7 V COMP 6.5 V T Junction Temperature Range -40 to 150 C j T Storage temperature range -40 to 150 C stg P Maximum power dissipation at Tamb = 25C1W tot Table 3. Thermal Data Symbol Parameter SO-16 HTSSOP16 HTSSOP16 (*) Unit R Thermal Resistance Junction to Ambient 120 110 50 C/W th j-amb (*) Device soldered on 1 S2P PC board Figure 3. Pins Connection (Top view) VREF 1 16 N.C. VREF 1 16 VCC OSC 2 15 LGATE OSC 2 15 VCC OCSET 3 14 PGND OCSET 3 14 LGATE SS/INH 4 13 BOOT SS/INH 4 13 PGND COMP 5 12 BOOT N.C. 5 12 HGATE FB 6 11 HGATE COMP 6 11 PHASE GND 7 10 PHASE FB 7 10 PGOOD GND 8 9 EAREF EAREF 8 9 PGOOD D03IN1510 D03IN1511 2/29