Datasheet

LP38858
www.ti.com
SNVS462D OCTOBER 2006REVISED APRIL 2013
Operating Ratings
(1)
V
IN
Supply Voltage (V
OUT
+ V
DO
) to V
BIAS
V
BIAS
Supply Voltage 3.0V to 5.5V
I
OUT
0 mA to 1.5A
Junction Temperature Range
(2)
40°C to +125°C
(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 ensure specific performance limits. For ensured specifications and conditions,
see the Electrical Characteristics.
(2) Device power dissipation must be de-rated based on device power dissipation (P
D
), ambient temperature (T
A
), and package junction to
ambient thermal resistance (θ
JA
). Additional heat-sinking may be required to ensure that the device junction temperature (T
J
) does not
exceed the maximum operating rating. See the Application Information section for details.
Electrical Characteristics
Unless otherwise specified: V
IN
= V
OUT(NOM)
+ 1V, V
BIAS
= 3.0V, I
OUT
= 10 mA, C
IN
= C
OUT
= 10 µF, C
BIAS
= 1 µF, C
SS
= open.
Limits in standard type are for T
J
= 25°C only; limits in boldface type apply over the junction temperature (T
J
) range of -40°C
to +125°C. Minimum and Maximum limits are ensured through test, design, or statistical correlation. Typical values represent
the most likely parametric norm at T
J
= 25°C, and are provided for reference purposes only.
Symbol Parameter Conditions MIN TYP MAX Units
V
OUT(NOM)
+ 1V V
IN
V
BIAS
,
-1.0 1.0
3.0V V
BIAS
5.5V, 0
-3.0 3.0
10 mA I
OUT
1.5A
V
OUT
V
OUT
Accuracy %
V
OUT(NOM)
+ 1V V
IN
V
BIAS
,
3.0V V
BIAS
5.5V,
-2.0 0 2.0
10 mA I
OUT
1.5A,
0°C T
J
+125°C
ΔV
OUT
/ΔV
IN
Line Regulation, V
IN
(1)
V
OUT(NOM)
+ 1V V
IN
V
BIAS
- 0.04 - %/V
ΔV
OUT
/ΔV
BIAS
Line Regulation, V
BIAS
(1)
3.0V V
BIAS
5.5V - 0.10 - %/V
ΔV
OUT
/ΔI
OUT
Output Voltage Load Regulation
(2)
10 mA I
OUT
1.5A - 0.2 - %/A
165
V
DO
Dropout Voltage
(3)
I
OUT
= 1.5A - 130 mV
180
LP38858-0.8 8.5
- 7.0
10 mA I
OUT
1.5A 9.0
Quiescent Current Drawn from V
IN
I
GND(IN)
mA
Supply
LP38858-1.2 12
11
10 mA I
OUT
1.5A 15
Quiescent Current Drawn from 3.8
I
GND(BIAS)
10 mA I
OUT
1.5A - 3.0 mA
V
BIAS
Supply 4.5
V
BIAS
rising until device is 2.20 2.70
UVLO Under-Voltage Lock-Out Threshold 2.45 V
functional 2.00 2.90
V
BIAS
falling from UVLO threshold 60 300
UVLO
(HYS)
Under-Voltage Lock-Out Hysteresis 150 mV
until device is non-functional 50 350
V
IN
= V
OUT(NOM)
+ 1V,
I
SC
Output Short-Circuit Current - 4.5 - A
V
BIAS
= 3.0V, V
OUT
= 0.0V
Soft-Start
LP38858-0.8 11.0 13.5 16.0
r
SS
Soft-Start internal resistance k
LP38858-1.2 13.5 16.0 18.5
LP38858-0.8, C
SS
= 10 nF - 675 -
Soft-Start time
t
SS
μs
t
SS
= C
SS
× r
SS
× 5
LP38858-1.2, C
SS
= 10 nF - 800 -
(1) Output voltage line regulation is defined as the change in output voltage from nominal value resulting from a change in input voltage.
(2) Output voltage load regulation is defined as the change in output voltage from nominal value as the load current increases from no load
to full load.
(3) Dropout voltage is defined the as input to output voltage differential (V
IN
- V
OUT
) where the input voltage is low enough to cause the
output voltage to drop 2% from the nominal value.
Copyright © 2006–2013, Texas Instruments Incorporated Submit Documentation Feedback 3
Product Folder Links: LP38858