NCP571, NCV571
http://onsemi.com
7
APPLICATIONS INFORMATION
A typical application circuit for the NCP571 series is
shown in Figure 2.
Input Decoupling (C1)
A 0.1 mF capacitor either ceramic or tantalum is
recommended and should be connected close to the NCP571
package. Higher values and lower ESR will improve the
overall line transient response.
Output Decoupling (C2)
The NCP571 is a stable Regulator and does not require
any specific Equivalent Series Resistance (ESR) or a
minimum output current. Capacitors exhibiting ESRs
ranging from a few mW up to 3.0 W can thus safely be used.
The minimum decoupling value is 0.1 mF and can be
augmented to fulfill stringent load transient requirements.
The regulator accepts ceramic chip capacitors as well as
tantalum devices. Larger output capacitors can be used
without fear of instabilities. Larger values improve noise
rejection and load regulation transient response.
Enable Operation
The enable pin will turn on or off the regulator. These
limits of threshold are covered in the electrical specification
section of this data sheet. If the enable is not used then the
pin should be connected to V
in
. It is not recommended to
leave this pin on air. In case the voltage of Enable signal is
higher then Input voltage of NCP571 device it is necessary
add an resistor divider in order to keep voltage at Enable pin
bellow Input voltage. A single gate device of VHC family
could be used for this logic level translation. The NL17SZ06
device could be chosen for non inverting open−drain buffer
as shown in Figure 19. Other possibility is using NL17SZ16
device as shown in Figure 20. More information is
mentioned in Application Note AND8101/D.
Figure 19.
Vin
Enable
V
in
GND
Enable
NC
GND
V
out
V
out
GND
C1
C2
0.1 mF
NL17SZ06
3.3 V
NCP571
0.1 mF
3.3 V
0 V
