Datasheet LTC3770 (Analog Devices) - 3
| Manufacturer | Analog Devices |
| Description | Fast No RSENSE Step-Down Synchronous Controller with Margining, Tracking and PLL |
| Pages / Page | 24 / 3 — ELECTRICAL CHARACTERISTICS. The. denotes specifi cations which apply over … |
| File Format / Size | PDF / 273 Kb |
| Document Language | English |
ELECTRICAL CHARACTERISTICS. The. denotes specifi cations which apply over the full operating
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LTC3770
ELECTRICAL CHARACTERISTICS The
l
denotes specifi cations which apply over the full operating temperature range, otherwise specifi cations are TA = 25°C. VIN = 15V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Main Control Loop
IQ Input DC Supply Current Normal Operation 1300 2200 μA Shutdown Supply Current 30 50 μA VFB Feedback Voltage Accuracy (Note 3) VREFIN = VREFOUT; ITH = 1.2V (0°C to 85°C) 0.596 0.6 0.604 V VREFIN = VREFOUT; ITH = 1.2V l 0.594 0.6 0.606 V VFB(LINEREG) Feedback Voltage Line Regulation VIN = 4V to 30V, ITH = 1.2V (Note 3) 0.002 %/V VFB(LOADREG) Feedback Voltage Load Regulation ITH = 0.5V to 1.9V (Note 3) –0.05 –0.3 % VRUN Run Pin On Threshold VRUN Rising 1 1.5 1.9 V ISS/TRACK Soft-Start Charging Current VSS/TRACK = 0V –1.1 –1.4 –1.7 μA IFB Feedback Pin Input Current –100 –20 100 nA gm(EA) Error Amplifi er Transconductance ITH = 1.2V (Note 3) l 1 1.3 1.6 mS VFCB Forced Continuous Threshold l 0.57 0.6 0.63 V IFCB Forced Continuous Pin Current VFCB = 0V –1 –2 μA tON On-Time ION = –60μA, VON = 1.5V 210 250 290 ns ION = –60μA, VON = 0V 90 115 150 ns tON(MIN) Minimum On-Time ION = –180μA, VON = 0V 50 100 ns tOFF(MIN) Minimum Off-Time Tested with a Square Wave (Note 5) 250 400 ns VSENSE(MAX) Maximum Current Sense Threshold VRNG = 1V, VFB = VREFIN – 30mV l 113 133 153 mV V – + SENSE – VSENSE VRNG = 0V, VFB = VREFIN – 30mV l 50 67 84 mV VRNG = INTVCC, VFB = VREFIN – 30mV l 228 268 308 mV VSENSE(MIN) Minimum Current Sense Threshold VRNG = 1V, VFB = VREFIN + 30mV –60 mV V – + SENSE – VSENSE VRNG = 0V, VFB = VREFIN + 30mV –30 mV VRNG = INTVCC, VFB = VREFIN + 30mV –120 mV ΔVFB(OV) Output Overvoltage Fault Threshold Offset 7 10 13 % V + IN(UVLO ) Undervoltage Lockout VIN Falling l 3.2 3.9 V V – IN(UVLO ) Undervoltage Lockout VIN Rising l 3.3 4 V VMGN(TH) MARGIN0, MARGIN1 Input Thresholds 1.4 V VMPGM MPGM Pin Voltage 1.18 V TG RUP TG Driver Pull-Up On Resistance TG High 1.9 2.5 Ω TG RDOWN TG Driver Pull-Down On Resistance TG Low 1.2 2.5 Ω BG RUP BG Driver Pull-Up On Resistance BG High 1.9 3 Ω BG RDOWN BG Driver Pull-Down On Resistance BG Low 0.7 1.5 Ω TG tr TG Rise Time CLOAD = 3300pF 20 ns TG tf TG Fall Time CLOAD = 3300pF 20 ns BG tr BG Rise Time CLOAD = 3300pF 20 ns BG tf BG Fall Time CLOAD = 3300pF 20 ns 3770fc 3
ELECTRICAL CHARACTERISTICS The
l
denotes specifi cations which apply over the full operating temperature range, otherwise specifi cations are TA = 25°C. VIN = 15V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Main Control Loop
IQ Input DC Supply Current Normal Operation 1300 2200 μA Shutdown Supply Current 30 50 μA VFB Feedback Voltage Accuracy (Note 3) VREFIN = VREFOUT; ITH = 1.2V (0°C to 85°C) 0.596 0.6 0.604 V VREFIN = VREFOUT; ITH = 1.2V l 0.594 0.6 0.606 V VFB(LINEREG) Feedback Voltage Line Regulation VIN = 4V to 30V, ITH = 1.2V (Note 3) 0.002 %/V VFB(LOADREG) Feedback Voltage Load Regulation ITH = 0.5V to 1.9V (Note 3) –0.05 –0.3 % VRUN Run Pin On Threshold VRUN Rising 1 1.5 1.9 V ISS/TRACK Soft-Start Charging Current VSS/TRACK = 0V –1.1 –1.4 –1.7 μA IFB Feedback Pin Input Current –100 –20 100 nA gm(EA) Error Amplifi er Transconductance ITH = 1.2V (Note 3) l 1 1.3 1.6 mS VFCB Forced Continuous Threshold l 0.57 0.6 0.63 V IFCB Forced Continuous Pin Current VFCB = 0V –1 –2 μA tON On-Time ION = –60μA, VON = 1.5V 210 250 290 ns ION = –60μA, VON = 0V 90 115 150 ns tON(MIN) Minimum On-Time ION = –180μA, VON = 0V 50 100 ns tOFF(MIN) Minimum Off-Time Tested with a Square Wave (Note 5) 250 400 ns VSENSE(MAX) Maximum Current Sense Threshold VRNG = 1V, VFB = VREFIN – 30mV l 113 133 153 mV V – + SENSE – VSENSE VRNG = 0V, VFB = VREFIN – 30mV l 50 67 84 mV VRNG = INTVCC, VFB = VREFIN – 30mV l 228 268 308 mV VSENSE(MIN) Minimum Current Sense Threshold VRNG = 1V, VFB = VREFIN + 30mV –60 mV V – + SENSE – VSENSE VRNG = 0V, VFB = VREFIN + 30mV –30 mV VRNG = INTVCC, VFB = VREFIN + 30mV –120 mV ΔVFB(OV) Output Overvoltage Fault Threshold Offset 7 10 13 % V + IN(UVLO ) Undervoltage Lockout VIN Falling l 3.2 3.9 V V – IN(UVLO ) Undervoltage Lockout VIN Rising l 3.3 4 V VMGN(TH) MARGIN0, MARGIN1 Input Thresholds 1.4 V VMPGM MPGM Pin Voltage 1.18 V TG RUP TG Driver Pull-Up On Resistance TG High 1.9 2.5 Ω TG RDOWN TG Driver Pull-Down On Resistance TG Low 1.2 2.5 Ω BG RUP BG Driver Pull-Up On Resistance BG High 1.9 3 Ω BG RDOWN BG Driver Pull-Down On Resistance BG Low 0.7 1.5 Ω TG tr TG Rise Time CLOAD = 3300pF 20 ns TG tf TG Fall Time CLOAD = 3300pF 20 ns BG tr BG Rise Time CLOAD = 3300pF 20 ns BG tf BG Fall Time CLOAD = 3300pF 20 ns 3770fc 3
