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 2.2µF 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
=
25°C 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
IN
= ( V
ONOM
+1)V. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = Vout/Vref = (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/1.235 = 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), 2.3
≤V
in
≤30V,
100µA≤I
L
≤
250 mA, T
J
≤
T
JMAX
.
Advanced Monolithic Systems, Inc.
www.advanced-monolithic.com
Phone (925) 443-0722
Fax (925) 443-0723
AMS2954
Note 8:
The junction-to-ambient thermal resistance are as follows:60°C/W for the TO-220 (T), 73°C/W for the TO-263 (M), 80°C/W for the TO-252 (D),
90°C/W for the SOT-223 (with package soldering to copper area over backside ground plane or internal power plane
ϕ
JA
can vary from 46°C/W to
>90°C/W
depending on mounting technique and the size of the copper area), 105°C/W for the molded plastic DIP (P) and 160°C/W for the molded plastic SO-8 (S).
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 5V
TAP
.
Note 12:
Output or reference voltage temperature coefficients 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 50mA 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 AMS2954 is tested at 150°C for I
L
= 1 mA. For I
L
= 100
µA
and T
J
= 125°C, line regulation is guaranteed by design to 0.2%.
See typical performance characteristics for line regulation versus temperature and load current.
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