Electrical Characteristics

Limits in standard typeface are for T

Unless otherwise specified: V

Symbol

Parameter

Conditions

Typ

(Note 4)

LP3855-ADJ (Note 5)

Units

Min

Max

Shutdown Input

V

SDT

Shutdown Threshold

Output = High

V

IN

2

V

Output = Low

0

0.3

T

dOFF

Turn-off delay

I

20

µs

T

dON

Turn-on delay

I

25

µs

I

SD

SD Input Current

V

1nA

AC Parameters

PSRR

Ripple Rejection

V

C

V

73

dB

V

C

V

57

ρ

n(l/f)

Output Noise Density

f = 120Hz

0.8

µV

e

n

Output Noise Voltage

BW = 10Hz – 100kHz

V

150

µV (rms)

BW = 300Hz – 300kHz

V

100

Note 1: Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating ratings indicate conditions for which the device is

intended to be functional, but does not guarantee specific performance limits. For guaranteed specifications and test conditions, see Electrical Characteristics. The

guaranteed specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed

test conditions.

Note 2: At elevated temperatures, devices must be derated based on package thermal resistance. The devices in TO220 package must be derated at

Note 3: The human body model is a 100pF capacitor discharged through a 1.5k

Ω resistor into each pin.

Note 4: Typical numbers are at 25˚C and represent the most likely parametric norm.

Note 5: Limits are guaranteed by testing, design, or statistical correlation.

Note 6: If used in a dual-supply system where the regulator load is returned to a negative supply, the output must be diode-clamped to ground.

if the voltage at the output terminal is forced to be higher than the voltage at the input terminal. This diode can typically withstand 200mA of DC current and 1Amp

of peak current.

Note 8: Output voltage line regulation is defined as the change in output voltage from the nominal value due to change in the input line voltage. Output voltage load

regulation is defined as the change in output voltage from the nominal value due to change in load current.

Note 9: Dropout voltage is defined as the minimum input to output differential voltage at which the output drops 2% below the nominal value. Dropout voltage

specification applies only to output voltages of 2.5V and above. For output voltages below 2.5V, the drop-out voltage is nothing but the input to output differential,

since the minimum input voltage is 2.5V.

Note 11: The SOT 223 package devices have slightly higher dropout due to increased bond wire resistance.

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