Datasheet LTC4020 (Analog Devices) - 3

LTC4020
e lecTrical characTerisTics The
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denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2). PVIN = SENSVIN = CSP = CSN = BAT = 20V, SHDN = 2V, C(TG1, BG1, TG2, BG2) = 1000pF, VRNG/SS = 2V. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
INTVCC Boost Refresh Supply Voltage ILOAD = 5mA l 4.85 5.0 5.15 V Boost Refresh Supply Dropout PVIN = 4.5V; IINTVCC = 5mA 4.46 V Boost Refresh Supply Short-Circuit Current VINTVCC = 0V l 85 150 mA Limit IPVIN PVIN Operating Current Note 3; ITH = 0V l 1.6 3 mA Shutdown Current VSHDN = 0 l 3 6 µA ISENSVIN SENSEVIN Operating Current l 0.25 0.5 mA Shutdown Current VSHDN = 0 l 25 60 µA ISENSTOP SENSETOP Operating Current 32.5 µA Shutdown Current VSHDN = 0 0.1 µA VFBMAX DC/DC Converter Reference Charging Terminated l 2.7 2.75 2.8 V SHDN IC Enable Threshold (Rising) l 1.175 1.225 1.275 V Threshold Hysteresis 100 mV SHDN Pin Bias Current 10 nA VSENS DC/DC Converter Inductor Current Limit VSENSVIN – VSENSTOP; l 45 50 60 mV (Average Value) VSENSGND – VSENSBOT Reverse Current Inhibit VITH Falling (TG2 Disabled) l 0 2 mV (Average Value) VITH Rising (TG2 Enabled) 6 mV ILIMIT Inductor Current Limit Programming VILIMIT = 0.5V; VILIMIT/VSENS(MAX) 20 V/V ILIMIT Pin Bias Current l 47.5 50 52.5 µA ITH Error Amp Current Limit VFBMAX = 0, VITH = 1.3V 8 µA Error Amp Transconductance VFBMAX = 2.75V; VITH = 1.3V 95 umho VC High Side Current Sense Transconductance (VSENSVIN – VSENSETOP) to IVC 200 umho VC = 1.8V Low Side Current Sense Transconductance (VSENSGND – VSENSEBOT) to IVC 200 umho VC = 1.8V DCMAX Maximum Duty Cycle BG2: tON • fO l 70 80 % fO Switching Frequency RRT = 100k l 235 250 265 kHz RRT = 50k 500 kHz RRT = 250k 100 kHz tON Minimum On Time BG2 l 150 250 ns tOFF Minimum Off Time TG1 l 300 500 ns tTR Gate Drive Transition Time TG1, BG1, TG2, BG2 5 ns tNOL Gate Drive Non-Overlap time (TG1 – SW1) to BG1, 75 ns (TG2 – SW2) to BG2 4020fd For more information www.linear.com/LTC4020 3 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Electrical Characteristics Pin Configuration Electrical Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Revision History Typical Application Related Parts