Datasheet LTC3877 (Analog Devices) - 3
| Hersteller | Analog Devices |
| Beschreibung | Dual Phase Step-Down Synchronous Controller with VID Output Voltage Programming and Low Value DCR Sensing |
| Seiten / Seite | 46 / 3 — e lecTrical characTerisTics The. denotes the specifications which apply … |
| Dateiformat / Größe | PDF / 1.1 Mb |
| Dokumentensprache | Englisch |
e lecTrical characTerisTics The. denotes the specifications which apply over the full operating
Modelllinie für dieses Datenblatt
Textversion des Dokuments
LTC3877
e lecTrical characTerisTics The
l
denotes the specifications which apply over the full operating junction temperature range, otherwise specifications are at TA = 25°C (Note 3). VIN = 15V, VRUN = 5V unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Main Control Loops
VIN Input Voltage Range 4.5 38 V VOUT Output Voltage Range When VID VINTVCC = 5.5V, Control Disabled With Low DCR Sensing (Note 10) 0.6 3.5 V Without Low DCR Sensing (Note 9) 0.6 5 V VOUT_VID Output Voltage When VID Control (Note 4) ITH1 Voltage = 1.2V Enabled (Diff Amp and Error Amp VID0,1,2,3,4,5 = 0V l 594 600 606 mV Included) VID0 = 1V, VID1,2,3,4,5 = 0V l 604 610 616 mV VID0,5 = 0V, VID1,2,3,4 = 1V l 891 900 909 mV VID1,2,3,4 = 0V, VID0,5 = 1V l 921 930 939 mV VID0,1,2,3,4,5 = 1V l 1.218 1.23 1.242 V IQ Input DC Supply Current (Note 5) Normal Operation VIN = 15V, VRUN = 5V, No Switching, EXTVCC Float 7.3 10 mA Shutdown VRUN = 0V 33 50 µA UVLO Undervoltage Lockout Threshold VINTVCC Ramping Down 3.6 3.8 4.1 V UVLOHYS UVLO Hysteresis 0.5 V V + FB2 Regulated VOUT Feedback Voltage (Note 4), ITH2 Voltage = 1.2V (–40°C to 85°C) 597 600 603 mV Including Diffamp Error (Channel 2) (Note 4), ITH2 Voltage = 1.2V (–40°C to 125°C) l 595.5 600 604.5 mV IFB1 Channel 1 Feedback Current (Note 4) 2 20 nA I + FB2 Channel 2 Feedback Current (Note 4) 40 100 nA DFMAX Maximum Duty Cycle In Dropout, fOSC = 625kHz l 94 96 % V + OVL Feedback Overvoltage Lockout Measured at VFB1, VFB2 650 670 690 mV VREFLNREG Reference Voltage Line Regulation VIN = 4.5V to 38V (Note 4) 0.002 0.01 %/V VLOADREG Output Voltage Load Regulation (Note 4) In Servo Loop; ∆ITH Voltage = 1.2V to 0.7V l 0.01 0.1 % In Servo Loop; ∆ITH Voltage = 1.2V to 1.6V l –0.01 –0.1 % gm1,2 EA Transconductance ITH1,2 Voltage = 1.2V; Sink/Source 5μA (Note 4) 2.5 mmho ITEMP DCR Temp. Compensation Current VITEMP = 0.5V 29 30 31 μA tSSINT Internal Soft Start Time VTK/SS = 5V (Note 8) 600 µs ITK/SS1,2 Soft Start Charge Current VTK/SS = 0V l 1.0 1.25 1.5 µA VRUN RUN Pin ON Threshold VRUN Rising l 1.1 1.22 1.35 V VRUN HYS RUN Pin ON Hysteresis 80 mV IRUN HYS RUN Pin Current Hysteresis 4.5 µA
Current Sensing
I + + SNSA AC Sense Pin Bias Current VSNSAn = 1V l 55 120 nA I + + SNSD DC Sense Pin Bias Current VSNSDn = 1V l 30 50 nA AVT_SNS Total Sense Gain to Current Comp 5 V/V 3877f For more information www.linear.com/LTC3877 3
e lecTrical characTerisTics The
l
denotes the specifications which apply over the full operating junction temperature range, otherwise specifications are at TA = 25°C (Note 3). VIN = 15V, VRUN = 5V unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Main Control Loops
VIN Input Voltage Range 4.5 38 V VOUT Output Voltage Range When VID VINTVCC = 5.5V, Control Disabled With Low DCR Sensing (Note 10) 0.6 3.5 V Without Low DCR Sensing (Note 9) 0.6 5 V VOUT_VID Output Voltage When VID Control (Note 4) ITH1 Voltage = 1.2V Enabled (Diff Amp and Error Amp VID0,1,2,3,4,5 = 0V l 594 600 606 mV Included) VID0 = 1V, VID1,2,3,4,5 = 0V l 604 610 616 mV VID0,5 = 0V, VID1,2,3,4 = 1V l 891 900 909 mV VID1,2,3,4 = 0V, VID0,5 = 1V l 921 930 939 mV VID0,1,2,3,4,5 = 1V l 1.218 1.23 1.242 V IQ Input DC Supply Current (Note 5) Normal Operation VIN = 15V, VRUN = 5V, No Switching, EXTVCC Float 7.3 10 mA Shutdown VRUN = 0V 33 50 µA UVLO Undervoltage Lockout Threshold VINTVCC Ramping Down 3.6 3.8 4.1 V UVLOHYS UVLO Hysteresis 0.5 V V + FB2 Regulated VOUT Feedback Voltage (Note 4), ITH2 Voltage = 1.2V (–40°C to 85°C) 597 600 603 mV Including Diffamp Error (Channel 2) (Note 4), ITH2 Voltage = 1.2V (–40°C to 125°C) l 595.5 600 604.5 mV IFB1 Channel 1 Feedback Current (Note 4) 2 20 nA I + FB2 Channel 2 Feedback Current (Note 4) 40 100 nA DFMAX Maximum Duty Cycle In Dropout, fOSC = 625kHz l 94 96 % V + OVL Feedback Overvoltage Lockout Measured at VFB1, VFB2 650 670 690 mV VREFLNREG Reference Voltage Line Regulation VIN = 4.5V to 38V (Note 4) 0.002 0.01 %/V VLOADREG Output Voltage Load Regulation (Note 4) In Servo Loop; ∆ITH Voltage = 1.2V to 0.7V l 0.01 0.1 % In Servo Loop; ∆ITH Voltage = 1.2V to 1.6V l –0.01 –0.1 % gm1,2 EA Transconductance ITH1,2 Voltage = 1.2V; Sink/Source 5μA (Note 4) 2.5 mmho ITEMP DCR Temp. Compensation Current VITEMP = 0.5V 29 30 31 μA tSSINT Internal Soft Start Time VTK/SS = 5V (Note 8) 600 µs ITK/SS1,2 Soft Start Charge Current VTK/SS = 0V l 1.0 1.25 1.5 µA VRUN RUN Pin ON Threshold VRUN Rising l 1.1 1.22 1.35 V VRUN HYS RUN Pin ON Hysteresis 80 mV IRUN HYS RUN Pin Current Hysteresis 4.5 µA
Current Sensing
I + + SNSA AC Sense Pin Bias Current VSNSAn = 1V l 55 120 nA I + + SNSD DC Sense Pin Bias Current VSNSDn = 1V l 30 50 nA AVT_SNS Total Sense Gain to Current Comp 5 V/V 3877f For more information www.linear.com/LTC3877 3