Datasheet LTC3374 (Analog Devices) - 4

LTC3374
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2). VCC = VIN1-8 = 3.3V, unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VVCC VCC Voltage Range l 2.7 5.5 V VVCC_UVLO Undervoltage Threshold on VCC VCC Voltage Falling l 2.35 2.45 2.55 V VCC Voltage Rising l 2.45 2.55 2.65 V IVCC_ALLOFF VCC Input Supply Current All Switching Regulators in Shutdown 8 18 µA IVCC VCC Input Supply Current At Least 1 Buck Active SYNC = 0V, RT = 400k, VFB_BUCK = 0.85V 45 75 µA SYNC = 2MHz 200 275 µA fOSC Internal Oscillator Frequency VRT = VCC, SYNC = 0V 1.8 2 2.2 MHz VRT = VCC, SYNC = 0V l 1.75 2 2.25 MHz RRT = 400k, SYNC = 0V l 1.8 2 2.2 MHz fSYNC Synchronization Frequency tLOW, tHIGH > 40ns 1 3 MHz VSYNC SYNC Level High l 1.2 V SYNC Level Low l 0.4 V VRT RT Servo Voltage RRT = 400k l 780 800 820 mV
Temperature Monitor
VTEMP(ROOM) TEMP Voltage at 25°C 150 mV ∆VTEMP/°C VTEMP Slope 6.75 mV/°C OT Overtemperature Shutdown Temperature Rising 165 °C OT Hyst Overtemperature Hysteresis 10 °C
1A Buck Regulators
VBUCK Buck Input Voltage Range l 2.25 5.5 V VOUT Buck Output Voltage Range VFB VIN V VIN_UVLO Undervoltage Threshold on VIN VIN Voltage Falling l 1.95 2.05 2.15 V VIN Voltage Rising l 2.05 2.15 2.25 V IVIN_BUCK Burst Mode® Operation VFB_BUCK = 0.85V (Note 4) 18 50 µA Forced Continuous Mode Operation ISW_BUCK = 0µA, VFB_BUCK = 0V 400 550 µA Shutdown Input Current All Switching Regulators in Shutdown 0 1 µA Shutdown Input Current At Least One Other Buck Active 1 2 µA IFWD PMOS Current Limit (Note 5) 2.0 2.3 2.7 A VFB Feedback Regulation Voltage l 780 800 820 mV IFB Feedback Leakage Current VFB_BUCK = 0.85V –50 50 nA DMAX Maximum Duty Cycle VFB_BUCK = 0V l 100 % RPMOS PMOS On-Resistance ISW_BUCK = 100mA 300 mΩ RNMOS NMOS On-Resistance ISW_BUCK = 100mA 300 mΩ ILEAKP PMOS Leakage Current EN_BUCK = 0 –2 2 µA ILEAKN NMOS Leakage Current EN_BUCK = 0 –2 2 µA tSS Soft-Start Time (Note 6) l 0.25 1 3 ms VPGOOD(FALL) Falling PGOOD Threshold Voltage % of Regulated VFB 92.5 % VPGOOD(HYS) PGOOD Hysteresis % of Regulated VFB 1 %
Buck Regulators Combined
IFWD2 PMOS Current Limit 2 Buck Converters Combined (Note 5) 4.6 A IFWD3 PMOS Current Limit 3 Buck Converters Combined (Note 5) 6.9 A IFWD4 PMOS Current Limit 4 Buck Converters Combined (Note 5) 9.2 A 3374fc 4 For more information www.linear.com/LTC3374 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Buck Switching Regulators Buck Regulators with Combined Power Stages Power Failure Reporting Via PGOOD_ALL Pin Temperature Monitoring and Overtemperature Protection Programming the Operating Frequency Applications Information Buck Switching Regulator Output Voltage and Feedback Network Buck Regulators Combined Buck Regulators Input and Output Decoupling Capacitor Selection PCB Considerations Package Description Revision History Typical Application Related Parts