Datasheet LT8608, LT8608B (Analog Devices) - 6

LT8608/LT8608B
TYPICAL PERFORMANCE CHARACTERISTICS Top FET Current Limit Top FET Current Limit vs Duty Cycle Top Fet Current Limit vs Duty Cycle vs T T emperature op FET Current Limit Vs Temperature Switch Drop vs Temperature Switch Drop vs Temperature
3.25 3.1 550 DUTY CYCLE = 0 SWITCH CURRENT = 1A 500 3.0 3.00 450 2.9 2.75 400 (A) 2.8 I SW 350 2.50 2.7 SWITCH DROP (mV) 300 TOP FET CURRENT LIMIT (A) 2.25 2.6 250 TOP SW BOT SW 2.00 2.5 200 0 20 40 60 80 100 –50 –10 30 70 110 150 –50 –30 –10 10 30 50 70 90 110 130 150 DUTY CYCLE (%) TEMPERATURE (°C) TEMPERATURE (°C) 8608 G10 8608 G11 8608 G12
Minimum On-Time Minimum Off-Time Switch Drop vs Switch Current vs Temperature Minimum On-Time Vs Temperature vs Temperature Minimum Off-Time Vs Temperature
800 40 110 IOUT = 1A 700 39 105 38 600 37 100 500 36 400 35 95 300 34 SWITCH DROP (mV) 90 33 200 MINIMUM ON-TIME (ns) MINIMUM OFF-TIME (ns) 32 85 100 31 TOP SW BOT SW 0 30 80 0 0.25 0.50 0.75 1 1.25 1.50 1.75 2 –50 –30 –10 10 30 50 70 90 110 130 150 –50 –30 –10 10 30 50 70 90 110 130 150 SWITCH CURRENT (A) TEMPERATURE (°C) TEMPERATURE (°C) 8608 G13 8608 G14 8608 G15
Switching Frequency Dropout Voltage vs Load Current vs Temperature Switching Frequency Vs Temperature Burst Frequency vs Load Current
750 2025 2500 L = XFL4020–222MEC 2020 2250 625 2015 2000 2010 1750 500 2005 1500 TAGE (mV) 375 2000 1250 1995 1000 250 1990 750 DROPOUT VOL SYNC = 0V OR LT8608 DFN SWITHCING FREQUENCY (kHz) 1985 SWITHCING FREQUENCY (kHz) 500 125 L = 2.2µH 1980 250 VIN = 12V VOUT = 3.3V RT = 18.2k VOUT = 3.3V 0 1975 0 0 0.25 0.50 0.75 1 1.25 1.50 1.75 2 –50 –10 30 70 110 150 0 100 200 300 400 500 LOAD CURRENT (A) TEMPERATURE (°C) LOAD CURRENT (mA) 8608 G16 8608 G17 8608 G18 Rev. E 6 For more information www.analog.com Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts