Datasheet LTC3778 (Analog Devices) - 2
| Manufacturer | Analog Devices |
| Description | Wide Operating Range, No RSENSE Step-Down Controller |
| Pages / Page | 24 / 2 — ABSOLUTE AXI U RATI GS. PACKAGE/ORDER I FOR ATIO. (Note 1). ELECTRICAL … |
| File Format / Size | PDF / 312 Kb |
| Document Language | English |
ABSOLUTE AXI U RATI GS. PACKAGE/ORDER I FOR ATIO. (Note 1). ELECTRICAL CHARACTERISTICS The
Model Line for this Datasheet
Text Version of Document
LTC3778
W W W U U W U ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1)
Input Supply Voltage (V TOP VIEW ORDER PART IN, ION) .. 36V to – 0.3V Boosted Topside Driver Supply Voltage NUMBER RUN/SS 1 20 BOOST (BOOST) ... 42V to – 0.3V V 2 19 ON TG LTC3778EF SENSE+, SW Voltage .. 36V to – 5V PGOOD 3 18 SW DRVCC, EXTVCC, (BOOST – SW), FCB, V 4 17 RNG SENSE+ RUN/SS, PGOOD Voltages .. 7V to – 0.3V I 5 16 TH SENSE– V FCB 6 15 PGND ON, VRNG Voltages ... INTVCC + 0.3V to – 0.3V I SGND 7 14 BG TH, VFB Voltages .. 2.7V to – 0.3V TG, BG, INTV I 8 13 ON DRVCC CC Peak Currents .. 2A TG, BG, INTV V 9 12 FB INTVCC CC RMS Currents .. 50mA EXTV 10 11 V Operating Ambient Temperature CC IN Range (Note 4) ... – 40°C to 85°C F PACKAGE 20-LEAD PLASTIC TSSOP Junction Temperature (Note 2) .. 125°C TJMAX = 125°C, θJA = 110°C/ W Storage Temperature Range ... – 65°C to 150°C Lead Temperature (Soldering, 10 sec).. 300°C Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications 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 900 2000 µA Shutdown Supply Current 15 30 µA VFB Feedback Reference Voltage ITH = 1.2V (Note 3) ● 0.594 0.600 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 % IFB Feedback Pin Input Current –5 ±100 nA gm(EA) Error Amplifier Transconductance ITH = 1.2V (Note 3) ● 1.4 1.7 2 mS VFCB Forced Continuous Threshold ● 0.57 0.6 0.63 V IFCB Forced Continuous Pin Current VFCB = 0.6V – 1 – 2 µA tON On-Time ION = 60µA, VON = 1.5V 200 250 300 ns ION = 60µA, VON = 0V 110 ns tON(MIN) Minimum On-Time ION = 180µA, VON = 0V 50 100 ns tOFF(MIN) Minimum Off-Time ION = 60µA, VON = 1.5V 250 400 ns VSENSE(MAX) Maximum Current Sense Threshold VRNG = 1V, VFB = 0.56V ● 113 133 153 mV V – + SENSE – VSENSE VRNG = 0V, VFB = 0.56V ● 79 93 107 mV VRNG = INTVCC, VFB = 0.56V ● 158 186 214 mV VSENSE(MIN) Minimum Current Sense Threshold VRNG = 1V, VFB = 0.64V 67 mV V + – SENSE – VSENSE VRNG = 0V, VFB = 0.64V 47 mV VRNG = INTVCC, VFB = 0.64V 93 mV ∆VFB(OV) Output Overvoltage Fault Threshold 7.5 10 12.5 % ∆VFB(UV) Output Undervoltage Fault Threshold 340 400 460 mV 3778f 2
W W W U U W U ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1)
Input Supply Voltage (V TOP VIEW ORDER PART IN, ION) .. 36V to – 0.3V Boosted Topside Driver Supply Voltage NUMBER RUN/SS 1 20 BOOST (BOOST) ... 42V to – 0.3V V 2 19 ON TG LTC3778EF SENSE+, SW Voltage .. 36V to – 5V PGOOD 3 18 SW DRVCC, EXTVCC, (BOOST – SW), FCB, V 4 17 RNG SENSE+ RUN/SS, PGOOD Voltages .. 7V to – 0.3V I 5 16 TH SENSE– V FCB 6 15 PGND ON, VRNG Voltages ... INTVCC + 0.3V to – 0.3V I SGND 7 14 BG TH, VFB Voltages .. 2.7V to – 0.3V TG, BG, INTV I 8 13 ON DRVCC CC Peak Currents .. 2A TG, BG, INTV V 9 12 FB INTVCC CC RMS Currents .. 50mA EXTV 10 11 V Operating Ambient Temperature CC IN Range (Note 4) ... – 40°C to 85°C F PACKAGE 20-LEAD PLASTIC TSSOP Junction Temperature (Note 2) .. 125°C TJMAX = 125°C, θJA = 110°C/ W Storage Temperature Range ... – 65°C to 150°C Lead Temperature (Soldering, 10 sec).. 300°C Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications 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 900 2000 µA Shutdown Supply Current 15 30 µA VFB Feedback Reference Voltage ITH = 1.2V (Note 3) ● 0.594 0.600 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 % IFB Feedback Pin Input Current –5 ±100 nA gm(EA) Error Amplifier Transconductance ITH = 1.2V (Note 3) ● 1.4 1.7 2 mS VFCB Forced Continuous Threshold ● 0.57 0.6 0.63 V IFCB Forced Continuous Pin Current VFCB = 0.6V – 1 – 2 µA tON On-Time ION = 60µA, VON = 1.5V 200 250 300 ns ION = 60µA, VON = 0V 110 ns tON(MIN) Minimum On-Time ION = 180µA, VON = 0V 50 100 ns tOFF(MIN) Minimum Off-Time ION = 60µA, VON = 1.5V 250 400 ns VSENSE(MAX) Maximum Current Sense Threshold VRNG = 1V, VFB = 0.56V ● 113 133 153 mV V – + SENSE – VSENSE VRNG = 0V, VFB = 0.56V ● 79 93 107 mV VRNG = INTVCC, VFB = 0.56V ● 158 186 214 mV VSENSE(MIN) Minimum Current Sense Threshold VRNG = 1V, VFB = 0.64V 67 mV V + – SENSE – VSENSE VRNG = 0V, VFB = 0.64V 47 mV VRNG = INTVCC, VFB = 0.64V 93 mV ∆VFB(OV) Output Overvoltage Fault Threshold 7.5 10 12.5 % ∆VFB(UV) Output Undervoltage Fault Threshold 340 400 460 mV 3778f 2
