Datasheet LTC3833 (Analog Devices) - 3

LTC3833
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating junction temperature range, otherwise specifications are at T + – A = 25°C. VIN = 15V, VFB = VOSNS – VOSNS , unless otherwise noted. (Note 4) SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS General
VIN Input Voltage Operating Range 4.5 38 V VOUT Output Voltage Operating Range 0.6 5.5 V IQ Input DC Supply Current Normal MODE/PLLIN = INTVCC 2 4 mA Shutdown Supply Current RUN = 0V 15 25 µA tON(MIN) Minimum On-Time VIN = 38V, VOUT = 0.6V 20 ns tOFF(MIN) Minimum Off-Time 90 ns
Output Sensing
VREG Regulated Differential Feedback Voltage ITH = 1.2V (Note 5) (V + – OSNS – VOSNS ) TA = 25°C 0.5985 0.6 0.6015 V TA = 0°C to 85°C l 0.596 0.6 0.604 V TA = –40°C to 125°C l 0.594 0.6 0.606 V Regulated Differential Feedback Voltage VIN = 4.5V to 38V, ITH = 0.5V to 1.9V, Over Line, Load and Common Mode V – OSNS = ±500mV (Note 5) (V + – OSNS – VOSNS ) TA = 0°C to 85°C l 0.594 0.6 0.606 V TA = –40°C to 125°C l 0.591 0.6 0.609 V gm(EA) Error Amplifier Transconductance ITH = 1.2V (Note 5) l 1.4 1.7 2 mS I + + VOSNS VOSNS Input Bias Current VFB = 0.6V ±5 ±25 nA I – – VOSNS VOSNS Input Bias Current VFB = 0.6V –35 –50 µA
Current Sensing
VSENSE(MAX) Valley Current Sense Threshold, VRNG = 2V, VFB = 0.57V l 80 100 120 mV V + – SENSE – VSENSE , VRNG = 0V, VFB = 0.57V l 22 30 38 mV Peak Current = Valley + Ripple VRNG = INTVCC, VFB = 0.57V l 39 50 61 mV VSENSE(MIN) Minimum Current Sense Threshold, VRNG = 2V, VFB = 0.63V –50 mV V + – SENSE – VSENSE , Forced Continuous VRNG = 0V, VFB = 0.63V –15 mV Mode VRNG = INTVCC, VFB = 0.63V –25 mV VSENSE(CM) SENSE+, SENSE– Voltage Range Referenced to Signal Ground (SGND) l –0.5 5.5 V (Common Mode) ISENSE SENSE+, SENSE– Input Bias Current VSENSE(CM) = 0.6V ±5 ±50 nA VSENSE(CM) = 5V 1 4 µA
Start-Up and Shutdown
VRUN(TH) RUN Pin On Threshold VRUN Rising l 1.1 1.2 1.3 V VRUN(HYS) RUN Pin Hysteresis 70 mV ISS Soft-Start Charging Current VTRACK/SS = 0V 1.0 µA UVLOLOCK INTVCC Undervoltage Lockout INTVCC Falling l 3.4 3.65 4.0 V UVLORELEASE INTVCC Undervoltage Lockout Release INTVCC Rising l 4.2 4.5 V
Switching Frequency and Clock Synchronization
f Free Running Switching Frequency RT = 205k 175 200 225 kHz RT = 80.6k 450 500 550 kHz RT = 18.2k 1800 2000 2200 kHz VCLK(IH) Clock Input High Level into MODE/PLLIN 2 V VCLK(IL) Clock Input Low Level into MODE/PLLIN 0.5 V 3833f 3