Datasheet LT1118, LT1118-2.5, LT1118-2.85, LT1118-5 (Analog Devices) - 6

LT1118/LT1118-2.5/ LT1118-2.85/LT1118-5
OPERATION
connected to the die substrate. Table 1 shows measured When the regulator is sinking load current, power dissipa- thermal resistance from junction to ambient for the LT1118 tion is nearly independent of VIN and can be calculated connected to various sized PC board ground planes. The as: power dissipated in the LT1118 varies with input voltage P and loading. When the regulator is sourcing current the D = VOUT • ILOAD power which must be dissipated by the package is: Heat sinking to the IC package must consider the worst case power dissipation which may occur. PD = (VIN – VOUT) • ILOAD
Table 1. Measured Thermal Resistance from Junction to Ambient for the LT1118 S8 Package SOT-223
Free Air 120°C/W 95°C/W 1 Sq Inch Copper 55°C/W 53°C/W 4 Sq Inch Copper 35°C/W 38°C/W
TYPICAL APPLICATIONS SCSI Active Terminator
110Ω • • • TERMPWR • 110Ω 110Ω 27 LINES 110Ω IN LT1118-2.85 OUT • GND • • 110Ω + • 5V 2.2μF 1μF 1118 TA03
Power Supply Splitter
VIN 5V 5V ANALOG 1μF IN LT1118-2.5 OUT COMMON 2.5V GND 1μF 1118 TA04 1118fd 6