STSR2PMCD-TR STMicroelectronics

STSR2P/ STSR2PM FORWARD SYNCHRONOUS RECTIFIERS SMART DRIVER SUPPLY VOLTAGE RANGE: 4.5V TO 5.5V TYPICAL PEAK OUTPUT CURRENT: SOURCE -2A, SINK 3.5A OPERATING FREQUENCY: 20 TO 750 KHZ SMART TURN-OFF ANTICIPATION TIMING OPERATION INDEPENDENT FROM THE FORWARD MAGNETIC RESET TECHNIQUE SO-8 POSSIBILITY TO OPERATE IN DISCONTINUOUS MODE DESCRIPTION anticipation in turning-off the OUT with GATE1 respect to the clock signal transition is provided, STSR2P Smart Driver IC provides two while the anticipation in turning off the OUT complementary high current outputs to drive GATE2 can be set through external components. The Power Mosfets. The IC is dedicated to properly adopted transitions revelation mechanism makes drive secondary Synchronous Rectifiers in circuit operation independent by the forward medium power, low output voltage, high efficiency magnetic reset technique used, avoiding most of Forward Converters. From a synchronizing clock the common problems inherent in self-driven input, STSR2P generates two driving signals with synchronous rectifiers. A special Inhibit function the self-setting of dead time between allows the shut-off of OUT . This feature complementary pulses. The IC operation prevents GATE2 makes discontinuous conduction mode possible secondary side shoot-through conditions and prevents the freewheeling mosfet from providing proper timing at the outputs turn-off sinking current from the output. transition. This smart function operates through a STSR2P automatically turns off the outputs when fast cycle-after-cycle control logic mechanism duty-cycle is lower than 13%, while STSR2PM based on an internal high frequency oscillator, works even at very low duty-cycle values. synchronized by the clock signal. A fixed SCHEMATIC DIAGRAM Vcc 2 5.7V + BIAS UVLO PEAK ANTICIPATION 3 SETANT2 CK 4 DETECTOR SET + + HIGH 1 OUTGate1 FREQUENCY DIGITAL OUTPUT OSCILLATOR BUFFERS CONTROL OUTGate2 7 - INHIBIT 5 + 25mV 6 8 SGLGND PWRGND September 2003 1/12STSR2P/STSR2PM ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit V DC Input Voltage -0.3 to 6 V CC V Max Gate Drive Output Voltage -0.3 to V V OUTGATE CC V Max INHIBIT Voltage (*) -0.6 to V V INHIBIT CC V Clock Input Voltage Range (*) -0.3 to V V CK CC I Switching Peak Current 2A LX P Continuous Power Dissipation at T =105C without heatsink 270 mW TOT A ESD Human Body Model Pins 1,2, 4, 5, 6, 7, 8 1KV Pin 3 0.9 KV T Storage Temperature Range -55 to +150 C stg T Operating Junction Temperature Range -40 to +125 C op Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. (*) A higher positive voltage level can be applied to the pin with a resistor which limits the current flowing into the pin to 10mA maximum THERMAL DATA Symbol Parameter SO-8 Unit R Thermal Resistance Junction-case 40 C/W thj-amb R Thermal Resistance Junction-ambient (*) 160 C/W thj-amb (*) This value is referred to one layer pcb board with minimum copper connections for the leads. a minimum value of 120 C/W can be obtained improving thermal conductivity of the board ORDERING CODES TYPE SO-8 SO-8 (T&R) STSR2P STSR2PCD STSR2PCD-TR STSR2PM STSR2PMCD STSR2PMCD-TR CONNECTION DIAGRAM (top view) 2/12