LP2978_09 Datasheet, PDF (4/8 Pages) National Semiconductor (TI) – Micropower SOT, 50 mA Low-Noise Ultra Low-Dropout Regulator Designed for Use with Very Low ESR Output Capacitors

Note 1: “Absolute Maximum Ratings” indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating
the device outside of its rated operating conditions.
Note 2: The ESD rating of pins 3 and 4 is 1 kV.
Note 3: The maximum allowable power dissipation is a function of the maximum junction temperature, T_J(MAX), the junction-to-ambient thermal resistance, θ_J-
A^{, and the ambient temperature, T}A^{. The maximum allowable power dissipation at any ambient temperture is calculated using:}
Where the value of θ_J-A for the SOT-23 package is 220°C/W in a typical PC board mounting. Exceeding the maximum allowable dissipation will cause excessive
die temperature, and the regulator will go into thermal shutdown.
Note 4: If used in a dual-supply system where the regulator load is returned to a negative supply, the LP2978 output must be diode-clamped to ground.
Note 5: The output PNP structure contains a diode between the V_IN to V_OUT terminals that is normally reverse-biased. Reversing the polarity from V_IN to V_OUT
will turn on this diode.
Note 6: Limits are 100% production tested at 25°C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality
Control (SQC) methods. The limits are used to calculate National's Average Outgoing Quality Level (AOQL).
Note 7: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below the value measured with a 1V differential.
Note 8: The ON/OFF input must be properly driven to prevent possible misoperation. For details, refer to Application Hints.
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100935 Version 6 Revision 2 Print Date/Time: 2009/04/23 16:08:18