si-3002kwf Allegro MicroSystems, Inc., si-3002kwf Datasheet - Page 6

• Manufacturer Part Number: si-3002kwf
• Description: 1 A, Low-dropout, Dual Output, 2.5 V & 3.3 V Regulator
• Manufacturer: Allegro MicroSystems, Inc.

Input Capacitor (C
either when the input line includes inductance or when the
wiring is long.
Output Capacitor (C
designed for a use with a very low ESR output capacitor
such as a ceramic capacitor. Output oscillation may occur
with that kind of capacitor.
ENABLE Input. The ENABLE (control) input features
an internal pull-up resistor. Leaving this input open causes
the output to turn on.
Parallel Operation. Parallel operation to increase load
current is not permitted.
Determination of DC Input Voltage. The minimum
input voltage V
fixed output voltage and the maximum rated dropout
voltage.
Overcurrent Protection. The SI-3000KWF series has
a built-in fold-back type overcurrent protection circuit,
which limits the output current at a start-up mode. It thus
cannot be used in applications that require current at the
start-up mode such as:
(1) constant-current load,
(2) power supply with positive and negative outputs to
common load (a center-tap type power supply), or
(3) raising the output voltage by putting a diode or a
resistor between the device ground and system ground.
Thermal Protection. Circuitry turns off the pass
transistor when the junction temperature rises above 135°C.
It is intended only to protect the device from failures due to
excessive junction temperatures and should not imply that
output short circuits or continuous overloads are permitted.
6
SI-3002KWF
1 A, Low-Dropout,
Dual Output,
2.5 V & 3.3 V Regulator
I
(min) should be higher than the sum of the
I
,
O
, 22 µF). This device is not
µF). This is necessary
APPLICATIONS INFORMATION
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036
Heat Radiation and Reliability. The reliability of the
IC is directly related to the junction temperature (T
operation. Accordingly, careful consideration should be
given to heat dissipation.
The inner frame on which the integrated circuit is mounted
is connected to the GND terminal (pin 3). Therefore, it is
very effective for heat radiation to enlarge the copper area
that is connected to the GND terminal. The graph on page
2 illustrates the effect of thermal resistance on the allow-
able package power dissipation.
The junction temperature (T
either of the following equations:
or
where P
R
D
JC
= I
= 7°C/W.
O1
(V
I
T
T
– V
J
J
= (P
= (P
O1
) + I
D
D
× R
× R
J
) can be determined from
O2
(V
JA
JC
) + T
) + T
I
– V
A
C
O2
) and
J
) in its