Datasheet LTC3786 (Analog Devices) - 3

LTC3786 ELECTRICAL CHARACTERISTICS
The
l
denotes the specifications which apply over the full operating junction temperature range, otherwise specifications are at TA = 25°C. VBIAS = 12V, unless otherwise noted (Note 2). SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Main Control Loop
VBIAS Chip Bias Voltage Operating Range 4.5 38 V VFB Regulated Feedback Voltage ITH = 1.2V (Note 4) l 1.188 1.200 1.212 V IFB Feedback Current (Note 4) ±5 ±50 nA VREFLNREG Reference Line Voltage Regulation VBIAS = 6V to 38V 0.002 0.02 %/V VLOADREG Output Voltage Load Regulation (Note 4) Measured in Servo Loop; l 0.01 0.1 % ∆ITH Voltage = 1.2V to 0.7V Measured in Servo Loop; l –0.01 –0.1 % ∆ITH Voltage = 1.2V to 2V gm Error Amplifier Transconductance ITH = 1.2V 2 mmho IQ Input DC Supply Current (Note 5) Pulse-Skipping or Forced Continuous Mode RUN = 5V; VFB = 1.25V (No Load) 0.8 mA Sleep Mode RUN = 5V; VFB = 1.25V (No Load) 55 80 µA Shutdown RUN = 0V 8 20 µA UVLO INTVCC Undervoltage Lockout Thresholds VINTVCC Ramping Up l 4.1 4.3 V VINTVCC Ramping Down l 3.6 3.8 V VRUN RUN Pin On Threshold VRUN Rising l 1.18 1.28 1.38 V VRUNHYS RUN Pin Hysteresis 100 mV IRUNHYS RUN Pin Hysteresis Current VRUN > 1.28V 4.5 µA IRUN RUN Pin Current VRUN < 1.28V 0.5 µA ISS Soft-Start Charge Current VSS = 0V 7 10 13 µA VSENSE(MAX) Maximum Current Sense Threshold VFB = 1.1V l 68 75 82 mV VSENSE(CM) SENSE Pins Common Mode Range (BOOST 2.5 38 V Converter Input Supply Voltage VIN) I + SENSE SENSE+ Pin Current VFB = 1.1V 200 300 µA I – SENSE SENSE– Pin Current VFB = 1.1V ±1 µA tr(TG) Top Gate Rise Time CLOAD = 3300pF (Note 6) 20 ns tf(TG) Top Gate Fall Time CLOAD = 3300pF (Note 6) 20 ns tr(BG) Bottom Gate Rise Time CLOAD = 3300pF (Note 6) 20 ns tf(BG) Bottom Gate Fall Time CLOAD = 3300pF (Note 6) 20 ns RUP(TG) Top Gate Pull-Up Resistance 1.2 Ω RDN(TG) Top Gate Pull-Down Resistance 1.2 Ω RUP(BG) Bottom Gate Pull-Up Resistance 1.2 Ω RDN(BG) Bottom Gate Pull-Down Resistance 1.2 Ω tD(TG/BG) Top Gate Off to Bottom Gate On Switch-On CLOAD = 3300pF (Each Driver) 80 ns Delay Time tD(BG/TG) Bottom Gate Off to Top Gate On Switch-On CLOAD = 3300pF (Each Driver) 80 ns Delay Time DFMAXBG Maximum BG Duty Factor 96 % tON(MIN) Minimum BG On-Time (Note 7) 110 ns 3786fc For more information www.linear.com/LTC3786 3