8220 Datasheet, PDF (7/8 Pages) Allegro MicroSystems – LOW-DROPOUT REGULATORS . HIGH EFFICIENCY

8220 THRU 8233
LOW-DROPOUT
REGULATORS
TYPICAL CHARACTERISTICS (concluded)
LOAD TRANSIENT PERFORMANCE
V_I = 3.2 V to 6.2 V, C_O = 4.7 µF, T_A = 25°C
ENABLE TRANSIENT PERFORMANCE
V_I = 3.2 V to 6.2 V, C_O = 1 µF, T_A = 25°C
+30 mV
V_O(nom)
-30 mV
2 µs
2 µs
50 mA
I_O
1 mA
Dwg. WP-028-3
V_O(nom)
V_O
0
V_I
V_E
0
<100 µs
<150 µs
Dwg. WP-027-3
APPLICATIONS INFORMATION
Linear regulators require input and output capacitors in order to
maintain over-all loop stability. The recommended minimum
value for the input capacitor is 0.1 µF. The output capacitor is
the dominant pole that provides the high-frequency compensa-
tion required for over-all regulator loop stability. These devices
are stable with as little as 1 µF. However, to ensure stable
operation under all conditions and capacitor types, the recom-
mended minimum value is 4.7 µF. The output capacitor may be
partially distributed through the load circuits. However, at least
1 µF should be connected at the regulator using the shortest and
widest foil pattern possible.
Thermal Considerations
These devices are intended to provide up to 100 mA of load
current in a very small package. The table on page 2 of this data
sheet gives the maximum allowable average output current for a
worst-case printed circuit design (R_θJA = 220°C/W with a
minimum footprint). Performance improvement is easily
accomplished with the addition of 1 square inch of copper at
terminal 2 (R_θJA = 170°C/W).
The products described here are manufactured under one or more
U.S. patents or U.S. patents pending.
Allegro MicroSystems, Inc. reserves the right to make, from time to
time, such departures from the detail specifications as may be required
to permit improvements in the performance, reliability, or
manufacturability of its products. Before placing an order, the user is
cautioned to verify that the information being relied upon is current.
Allegro products are not authorized for use as critical components
in life-support devices or systems without express written approval.
The information included herein is believed to be accurate and
reliable. However, Allegro MicroSystems, Inc. assumes no responsi-
bility for its use; nor for any infringement of patents or other rights of
third parties which may result from its use.
www.allegromicro.com