AAT3221IGV-3.0-T1 Analogic Tech, AAT3221IGV-3.0-T1 Datasheet - Page 9

• Manufacturer Part Number: AAT3221IGV-3.0-T1
• Description: Low Dropout (LDO) Regulators 150mA NanoPower LDO Linear Regulator
• Manufacturer: Analogic Tech

Specifications of AAT3221IGV-3.0-T1

• Number Of Outputs: 1
• Polarity: Positive
• Input Voltage Max: 7 V
• Output Voltage: 3 V
• Output Type: Fixed
• Dropout Voltage (max): 0.225 V at 100 mA
• Output Current: 150 mA
• Line Regulation: 0.4 % / V
• Load Regulation: 1.15 %
• Voltage Regulation Accuracy: 2 %
• Maximum Power Dissipation: 0.667 W
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: SOT-23-5
• Minimum Operating Temperature: - 40 C
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PowerLinear
Applications Information
To ensure that the maximum possible performance is
obtained from the AAT3221/2, please refer to the follow-
ing application recommendations.
Input Capacitor
A 1μF or larger capacitor is typically recommended for
C
for basic LDO regulator operation.
AAT3221/2 is physically located any distance more than
one or two centimeters from the input power source, a
C
should be located as closely to the device V
practically possible.
offer superior input line transient response and will
assist in maximizing the power supply ripple rejection.
Ceramic, tantalum, or aluminum electrolytic capacitors
may be selected for C
ESR requirement.
operation, ceramic capacitors are recommended for C
due to their inherent capability over tantalum capacitors
to withstand input current surges from low impedance
sources such as batteries in portable devices.
Output Capacitor
For proper load voltage regulation and operational sta-
bility, a capacitor is required between pins V
The C
ground pin should be made as direct as practically pos-
sible for maximum device performance. The AAT3221/2
has been specifically designed to function with very low
ESR ceramic capacitors. Although the device is intended
to operate with these low ESR capacitors, it is stable
over a wide range of capacitor ESR, thus it will also work
with some higher ESR tantalum or aluminum electrolytic
capacitors.
capacitors are recommended.
The value of C
however, 1μF is sufficient for most operating conditions.
If large output current steps are required by an applica-
tion, then an increased value for C
ered. The amount of capacitance needed can be calcu-
lated from the step size of the change in output load
current expected and the voltage excursion that the load
can tolerate.
3221.2007.11.1.12
IN
IN
in most applications. A C
capacitor will be needed for stable operation.
OUT
capacitor connection to the LDO regulator
However, for best performance, ceramic
OUT
TM
typically ranges from 0.47μF to 10μF;
For 150mA LDO regulator output
IN
C
, as there is no specific capacitor
IN
values greater than 1μF will
IN
capacitor is not required
OUT
should be consid-
However, if the
OUT
w w w . a n a l o g i c t e c h . c o m
and GND.
IN
pin as
C
IN
IN
150mA NanoPower™ LDO Linear Regulator
The total output capacitance required can be calculated
using the following formula:
Where:
Note that use of this equation results in capacitor values
approximately two to four times the typical value needed
for an AAT3221/2 at room temperature. The increased
capacitor value is recommended if tight output toler-
ances must be maintained over extreme operating con-
ditions and maximum operational temperature excur-
sions. If tantalum or aluminum electrolytic capacitors
are used, the capacitor value should be increased to
compensate for the substantial ESR inherent to these
capacitor types.
Capacitor Characteristics
Ceramic composition capacitors are highly recommend-
ed over all other types of capacitors for use with the
AAT3221/2. Ceramic capacitors offer many advantages
over their tantalum and aluminum electrolytic counter-
parts. A ceramic capacitor typically has very low ESR, is
lower cost, has a smaller PCB footprint, and is non-
polarized. Line and load transient response of the LDO
regulator is improved by using low-ESR ceramic capaci-
tors. Since ceramic capacitors are non-polarized, they
are less prone to damage if incorrectly connected.
Equivalent Series Resistance (ESR)
ESR is a very important characteristic to consider when
selecting a capacitor. ESR is the internal series resis-
tance associated with a capacitor, which includes lead
resistance, internal connections, capacitor size and area,
material
Typically, capacitor ESR is measured in milliohms for
ceramic capacitors and can range to more than several
ohms for tantalum or aluminum electrolytic capacitors.
Ceramic Capacitor Materials
Ceramic capacitors less than 0.1μF are typically made
from NPO or C0G materials. NPO and C0G materials are
typically tight tolerance and very stable over tempera-
ture. Larger capacitor values are typically composed of
ΔI = maximum step in output current
ΔV = maximum excursion in voltage that the load can
tolerate
composition,
C
OUT
PRODUCT DATASHEET
=
AAT3221/2
and
ΔV
ΔI
· 15µF
ambient
temperature.
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