LM34904 Datasheet, PDF (4/9 Pages) Texas Instruments – 500mA Current Limited Power Switch

LM34904
Thermal Characteristics
Symbol
θ_JA1
θ_JA2
T_SD
Description
Junction-to-Ambient
Thermal Resistance
Junction-to-Ambient
Thermal Resistance
Thermal Shutdown
Threshold
Conditions
Typical Value
Mount device on a standard 4-layer 4" x 3" JEDEC board. Apply known
amount of power to the package. Measure junction temperature and
104
surrounding air temperature. No air flow. Refer to JESD51-7 for more
information.
Mount device on a 2-layer 2.19" x 2.9" board. Copper thickness is 1 oz
per layer. No air flow. Power dissipation is 0.5W.
136
Raise T_J from below 120°C until POK is de-asserted. No load is
135
connected at ACC_PWR.
Unit
°C/W
°C/W
°C
Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the
device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the
Electrical Characteristics table.
Note 2: The voltages on these pins should never exceed VCC+0.3V.
Note 3: The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. Test method is per JESD-22-A114.
Note 4: For VCC between 2.2V and 2.8V, if ENABLE is a logic low, the LM34904 will not turn on the PFET switch.
Note 5: If ENABLE toggles low from a high state, it needs to stay low for at least T₃ long before toggling back to high. Otherwise the internal flip-flop may not be
set and the PFET switch may not turn on.
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