LTC3608 e lectrical characteristics The l denotes the specifications which apply over the full operating junction temperature range, otherwise specifications are at TA = 25°C. VIN = 15V unless otherwise noted. SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITSMain Control Loop SVIN Operating Input Voltage Range 4 18 V IQ Input DC Supply Current Normal 900 2000 µA Shutdown Supply Current 15 30 µA VFB Feedback Reference Voltage ITH = 1.2V, –40°C to 85°C (Note 3) 0.594 0.600 0.606 V ITH = 1.2V, –40°C to 125°C (Note 3) l 0.590 0.600 0.610 V ΔVFB(LINEREG) Feedback Voltage Line Regulation VIN = 4V to 18V, ITH = 1.2V (Note 3) 0.002 %/V ΔVFB(LOADREG) Feedback Voltage Load Regulation ITH = 0.5V to 1.9V (Note 3) –0.05 –0.3 % IFB Feedback Input Current VFB = 0.6V –5 ±50 nA gm(EA) Error Amplifier Transconductance ITH = 1.2V (Note 3) l 1.4 1.7 2 mS VFCB Forced Continuous Threshold l 0.54 0.6 0.66 V IFCB Forced Continuous Pin Current VFCB = 0.6V –1 –2 µA tON On-Time ION = 60µA, VON = 1.5V 220 280 340 ns ION = 60µA, VON = 0V 110 ns tON(MIN) Minimum On-Time ION = 180µA, VON = 0V 60 100 ns tOFF(MIN) Minimum Off-Time ION = 30µA, VON = 1.5V 320 500 ns IVALLEY(MAX) Maximum Valley Current VRNG = 0.5V, VFB = 0.56V, FCB = 0V l 5 11 A VRNG = 0V, VFB = 0.56V, FCB = 0V l 8 16 A IVALLEY(MIN) Maximum Reverse Valley Current VRNG = 0.5V, VFB = 0.64V, FCB = 0V 5.5 A VRNG = 0V, VFB = 0.64V, FCB = 0V 7.5 A ΔVFB(OV) Output Overvoltage Fault Threshold 7 10 13 % VRUN/SS(ON) RUN Pin Start Threshold l 0.8 1.5 2 V VRUN/SS(LE) RUN Pin Latchoff Enable Threshold RUN/SS Pin Rising 4 4.5 V VRUN/SS(LT) RUN Pin Latchoff Threshold RUN/SS Pin Falling 3.5 4.2 V IRUN/SS(C) Soft-Start Charge Current VRUN/SS = 0V –0.5 –1.2 –3 µA IRUN/SS(D) Soft-Start Discharge Current VRUN/SS = 4.5V, VFB = 0V 0.8 1.8 3 µA VIN(UVLO) Undervoltage Lockout INTVCC Falling l 3.4 3.9 V VIN(UVLOR) Undervoltage Lockout Release INTVCC Rising l 3.5 4 V RDS(ON) Top Switch On-Resistance 10 19 mΩ Bottom Switch On-Resistance 8 14 mΩ 3608fc Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts