SP6201ER-L Datasheet, PDF (14/17 Pages) Exar Corporation – 100mA/200mA Micropower CMOS LDO Regulators

SP6200 / SP6201
100mA/200mA Micropower CMOS LDO Regulators
regulator's transient response. The output
capacitor value may be increased without
limit. The output capacitor should have an ESR
(effective series resistance) below 5Ω and a
resonant frequency above 1MHz.
NO LOAD STABILITY
The SP6200/SP6201 will remain stable and in
regulation with no external load (other than
the internal voltage driver) unlike many other
voltage regulators. This is especially important
in CMOS RAM keep-alive applications.
THERMAL CONSIDERATIONS
The SP6200 is designed to provide 100mA of
continuous current, while the SP6201 will
provide 200mA of continuous current.
Maximum power dissipation can be calculated
based on the output current and the voltage
drop across the part. To determine the
maximum power dissipation in the package,
use the junction-to-ambient thermal
resistance of the device and the following
basic equation:
T_J(MAX) is the maximum junction temperature of
the die and is 125°C. T_A is the ambient
operating. θ_JA is the junction-to-ambient
thermal resistance for the regulator and is
layout dependent.
The actual power dissipation of the regulator
circuit can be determined using one simple
equation:
To prevent the device from entering thermal
shutdown, maximum power dissipation cannot
be exceeded. Using the output voltage of 3.0V
and an output current of 200mA, the
maximum input voltage can be determined.
Ground pin current can be taken from the
electrical spec’s table (I_GND=200µA at
I_OUT=200mA). The maximum input voltage is
determined as follows:
Solving for V_IN, we get:
After calculations, we find that the maximum
input voltage of a 3.0V application at 200mA
of output current in an SOT-23-5 package is
5.59V.
DUAL-SUPPLY OPERATION
When used in dual supply systems where the
regulator load is returned to a negative
supply, the output voltage must be diode
clamped to ground.
Substituting P_D(max) for P_D and solving for the
operating conditions that are critical to the
application will give the maximum operating
conditions for the regulator circuit. For
example, if we are operating the SP6201- 3.0V
at room temperature, with a SOT-23-5
package on a 4 layer standard board we can
determine the maximum input voltage for a
set output current.
© 2012 Exar Corporation
14/17
Rev. 2.1.0