Datasheet LTC3612 (Analog Devices) - 3

LTC3612
elecTrical characTerisTics The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2). VIN = 3.3V, RT/SYNC = SVIN, unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VIN Operating Voltage Range l 2.25 5.5 V VUVLO Undervoltage Lockout Threshold SVIN Ramping Down l 1.7 V SVIN Ramping Up l 2.25 V VFB Feedback Voltage Internal Reference (Notes 3, 4) VTRACK/SS = SVIN, VDDR = 0V 0°C < TJ < 85°C 0.594 0.6 0.606 V –40°C < TJ < 125°C l 0.591 0.609 V –55°C < TJ < 150°C l 0.589 0.611 V Feedback Voltage External Reference (Notes 3, 4) VTRACK/SS = 0.3V, VDDR = SVIN 0.289 0.3 0.311 V (Note 7) (Notes 3, 4) VTRACK/SS = 0.5V, VDDR = SVIN 0.489 0.5 0.511 V IFB Feedback Input Current VFB = 0.6V l ±30 nA ∆VLINEREG Line Regulation SVIN = PVIN = 2.25V to 5.5V l 0.2 %/V (Notes 3, 4) TRACK/SS = SVIN ∆VLOADREG Load Regulation ITH from 0.5V to 0.9V (Notes 3, 4) 0.25 % VITH = SVIN (Note 5) 2.6 % IS Active Mode VFB = 0.5V, VMODE = SVIN (Note 6) 1100 µA Sleep Mode VFB = 0.7V, VMODE = 0V, ITH = SVIN 70 100 µA (Note 5) VFB = 0.7V, VMODE = 0V (Note 4) 120 160 µA Shutdown SVIN = PVIN = 5.5V, VRUN = 0V 0.1 1 µA RDS(ON) Top Switch On-Resistance PVIN = 3.3V (Note 10) 70 mΩ Bottom Switch On-Resistance PVIN = 3.3V (Note 10) 45 mΩ ILIM Top Switch Current Limit Sourcing (Note 8), VFB = 0.5V Duty Cycle <35% 5.2 6 6.8 A Duty Cycle = 100% 3.7 A Bottom Switch Current Limit Sinking (Note 8), VFB = 0.7V, –3 –4 –5 A Forced Continuous Mode gm(EA) Error Amplifier Transconductance –5µA < IITH < 5µA (Note 4) 200 µS IEAO Error Amplifier Max Output Current (Note 4) ±30 µA tSS Internal Soft-Start Time VFB from 0.06V to 0.54V, 0.65 1 1.5 ms TRACK/SS = SVIN VTRACK/SS Enable Internal Soft-Start (Note 7 ) 0.62 V tTRACK/SS_DIS Soft-Start Discharge Time at 70 µs Start-Up RON(TRACK/SS_DIS) TRACK/SS Pull-Down Resistor at 200 Ω Start-Up fOSC Oscillator Frequency RT/SYNC = 370k l 0.8 1 1.2 MHz Internal Oscillator Frequency VRT/SYNC = SVIN l 1.8 2.25 2.7 MHz fSYNC Synchronization Frequency 0.3 4 MHz VRT/SYNC SYNC Level High 1.2 V SYNC Level Low . 0.3 V ISW(LKG) Switch Leakage Current SVIN = PVIN = 5.5V, VRUN = 0V 0.1 1 µA VDDR DDR Option Enable Voltage SVIN – 0.3 V VMODE Internal Burst Mode Operation 0.3 V (Note 9) Pulse-Skipping Mode SVIN – 0.3 V Forced Continuous Mode 1.1 SVIN • 0.58 V External Burst Mode Operation 0.45 0.8 V 3612fc For more information www.linear.com/LTC3612 3 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Operation Applications Information Package Description Typical Application Related Parts