LTC3866 e lecTrical characTerisTics The l denotes the specifications which apply over the specified operatingjunction temperature range, otherwise specifications are at TA = 25°C (Note 2). VIN = 15V, VRUN = 5V unless otherwise specified.SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITSOn-Chip Driver TG RUP TG Pull-Up RDS(ON) TG High 2.6 Ω TG RDOWN TG Pull-Down RDS(ON) TG Low 1.5 Ω BG RUP BG Pull-Up RDS(ON) BG High 2.4 Ω BG RDOWN BG Pull-Down RDS(ON) BG Low 1.1 Ω Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 4: This IC includes overtemperature protection that is intended to may cause permanent damage to the device. Exposure to any Absolute protect the device during momentary overload conditions. The maximum Maximum Rating condition for extended periods may affect device rated junction temperature will be exceeded when this protection is active. reliability and lifetime. Continuous operation above the absolute maximum operating junction Note 2: The LTC3866 is tested under pulsed load conditions such that temperature may impair device reliability or permanently damage the T device. J ≈ TA. The LTC3866E is guaranteed to meet performance specifications from 0°C to 85°C operating junction temperature. Specifications over Note 5: The LTC3866 is tested in a feedback loop that servos VITH to a the –40°C to 125°C operating junction temperature range are assured by specified voltage and measures the resultant VFB. design, characterization and correlation with statistical process controls. Note 6: Dynamic supply current is higher due to the gate charge being The LTC3866I is guaranteed to meet performance specifications over the delivered at the switching frequency. See Applications Information. full –40°C to 125°C operating junction temperature range. The maximum Note 7: Rise and fall times are measured using 10% and 90% levels. Delay ambient temperature consistent with these specifications is determined times are measured using 50% levels. by specific operating conditions in conjunction with board layout, the package thermal impedance and other environmental factors. Note 8: The minimum on-time condition corresponds to the on inductor peak-to-peak ripple current ≥40% of I Note 3: The junction temperature, T MAX (see Minimum On-Time J, is calculated from the ambient Considerations in the Applications Information section). temperature, TA, and power dissipation, PD, according to the following formula: Note 9: Guaranteed by design. LTC3866FE: TJ = TA + (PD • 33°C/W) LTC3866UF: TJ = TA + (PD • 47°C/W) Typical perForMance characTerisTics TA = 25°C, unless otherwise noted.Efficiency vs Load CurrentEfficiency vs Load CurrentEfficiency and Power Lossand Modeand Modevs Load Current 100 100 95 15 VIN = 20V 90 94 90 93 VOUT = 1.5V 80 80 92 FRONT PAGE CIRCUIT 70 91 70 POWER LOSS (W) 90 10 EFFICIENCY 60 60 89 V V 50 IN = 4.5V IN = 12V 88 V 50 OUT = 1.5V VOUT = 1.5V 87 40 L = 0.33µH 40 L = 0.33µH 86 EFFICIENCY (%) (DCR = 0.32mΩ TYP) EFFICIENCY (%) (DCR = 0.32mΩ TYP) EFFICIENCY (%) 30 85 5 FRONT PAGE CIRCUIT 30 FRONT PAGE CIRCUIT POWER LOSS 84 20 CCM CCM PULSE SKIPPING 20 PULSE SKIPPING 83 10 Burst Mode 82 10 Burst Mode OPERATION OPERATION 81 0 0 80 0 0.01 0.1 1 10 100 0.01 0.1 1 10 100 0 5 10 15 20 25 30 35 LOAD CURRENT (A) LOAD CURRENT (A) LOAD CURRENT (A) 3866 G01 3866 G02 3866 G03 3866fc For more information www.linear.com/LTC3866 5 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts