Electrical Characteristics
(Note 2) (Continued)
Parameter
Conditions
(Note 2)
LP2951
LP2950AC-XX
LP2951AC-XX
Tested
Limit
(Note 3)
LP2950C-XX
LP2951C-XX
Tested
Limit
(Note 3)
Units
Tested
Limit
(Notes 3, 16)
Design
Limit
(Note 4)
Design
Limit
(Note 4)
Typ
Typ
Typ
Shutdown Input
Shutdown Pin Input
Current
V
shutdown
= 2.4V
30
50
100
600
750
10
20
30
50
30
50
μA max
μA max
μA max
μA max
μA max
μA max
100
100
V
shutdown
= 30V
450
450
600
450
600
750
750
Regulator Output
Current in Shutdown
(Note 11)
3
3
10
3
10
20
20
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 tables.
Note 2:
Unless otherwise specified all limits guaranteed for V
IN
= (V
ONOM
+ 1)V, I
L
= 100 μA and C
L
= 1 μF for 5V versions and 2.2 μF for 3V and 3.3V versions.
Limits appearing in
boldface
type apply over the entire junction temperature range for operation. Limits appearing in normal type apply for T
A
= T
J
= 25C. Additional
conditions for the 8-pin versions are FEEDBACK tied to V
TAP
, OUTPUT tied to SENSE, and V
SHUTDOWN
≤
0.8V.
Note 3:
Guaranteed and 100% production tested.
Note 4:
Guaranteed but not 100% production tested. These limits are not used to calculate outgoing AQL levels.
Note 5:
Dropout Voltage is defined as the input to output differential at which the output voltage drops 100 mV below its nominal value measured at 1V differential.
At very low values of programmed output voltage, the minimum input supply voltage of 2V (2.3V over temperature) must be taken into account.
Note 6:
Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the nominal reference voltage measured at
V
= (V
NOM + 1)V. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = V
/V
= (R1 + R2)/R2.
For example, at a programmed output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x 5V/1.235V = 384 mV.
Thresholds remain constant as a percent of V
out
as V
out
is varied, with the dropout warning occurring at typically 5% below nominal, 7.5% guaranteed.
Note 7:
V
ref
≤
V
out
≤
(V
in
1V), 2.3V
≤
V
in
≤
30V, 100 μA
≤
I
L
≤
100 mA, T
J
≤
T
JMAX
.
Note 8:
The junction-to-ambient thermal resistances are as follows: 180C/W and 160C/W for the TO-92 package with 0.40 inch and 0.25 inch leads to the printed
circuit board (PCB) respectively, 105C/W for the molded plastic DIP (N), 130C/W for the ceramic DIP (J), 160C/W for the molded plastic SOP (M), 200C/W for the
molded plastic MSOP (MM), and 160C/W for the metal can package (H). The above thermal resistances for the N, J, M, and MM packages apply when the package
is soldered directly to the PCB. Junction-to-case thermal resistance for the H package is 20C/W.
Note 9:
May exceed input supply voltage.
Note 10:
When used in dual-supply systems where the output terminal sees loads returned to a negative supply, the output voltage should be diode-clamped to
ground.
Note 11:
V
shutdown
≥
2V, V
in
≤
30V, V
out
= 0, Feedback pin tied to V
TAP
.
Note 12:
Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Note 13:
Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load or line regulation
effects. Specifications are for a 50 mA load pulse at V
IN
= 30V (1.25W pulse) for T = 10 ms.
Note 14:
Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are
covered under the specification for thermal regulation.
Note 15:
Line regulation for the LP2951 is tested at 150C for I
=1 mA. For I
=100 μAand T
J
=125C, line regulation is guaranteed by design to 0.2%. See Typical
Performance Characteristics for line regulation versus temperature and load current.
Note 16:
A Military RETS specification is available on request. At time of printing, the LP2951 RETS specification complied with the boldface limits in this column.
The LP2951H, WG, or J may also be procured as Standard Military Drawing Spec
#
5962-3870501MGA, MXA, or MPA.
Note 17:
All LP2950 devices have the nominal output voltage coded as the last two digits of the part number. In the LP2951 products, the 3.0V and 3.3V versions
are designated by the last two digits, but the 5V version is denoted with no code at this location of the part number (refer to ordering information table).
Typical Performance Characteristics
Quiescent Current
DS008546-27
Dropout Characteristics
DS008546-28
Input Current
DS008546-29
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