NCP330
www.onsemi.com
8
FUNCTIONAL DESCRIPTION
Overview
The NCP330 is a high side N−channel MOSFET power
distribution switch designed to connect external voltage
directly to the system. The high side MOSFET is
automatically turned on if the Vin voltage is applied thanks
to internal pull up connected between Vin and EN pin. The
turned off is obtained by Vin removal. Due to the soft start
circuitry, NCP330 is able to limit large voltage surges.
Enable input
Enable pin is an active high. The part is off when Vin is not
present, limiting current consumption from battery to OUT
pin.
In the other side, the part is automatically turned on when
V
IN
is applied.
Blocking Control
The blocking control circuitry switches the bulk of the
power NMOS. When the part is off (No V
IN
or EN tied to
GND externally) , the body diode limits the leakage current
I
REV
from OUT to IN. In this mode, anode of the body diode
is connected to IN pin and cathode is connected to OUT pin.
In operating condition, anode of the body diode is connected
to OUT pin and cathode is connected to IN pin preventing
the discharge of the power supply.
Cin Capacitor
A IN capacitor, 1 mF, at least, capacitor must be placed as
close as possible the part to be Compliant with
IEC61000−4−2 (Level 4).
Cout Capacitor
Depending on the sinking current during system start up
and system turn off, a capacitor must be placed on the output.
A 1 mF is strongly recommended but can be decreased down
to 100 nF if the above two sequences are well controlled and
parasitic inductance connected on the Vout line is negligible.
APPLICATION INFORMATION
Power Dissipation
The device’s junction temperature depends on different
contributor factor such as board layout, ambient
temperature, device environment, etc... Yet, the main
contributor in term of junction temperature is the power
dissipation of the power MOSFET. Assuming this, the
power dissipation and the junction temperature in normal
mode can be calculated with the following equations:
P
D
+ R
DS(on)
ǒ
I
OUT
Ǔ
2
P
D
= Power dissipation (W)
R
DS(on)
= Power MOSFET on resistance (W)
I
OUT
= Output current (A)
T
J
+ P
D
R
qJA
) T
A
T
J
= Junction temperature (°C
R
q
JA
= Package thermal resistance (°C/W)
T
A
= Ambient temperature (°C)
PCB Recommendations
The NCP330 integrates an up to 3 A rated NMOS FET,
and the PCB design rules must be respected to properly
evacuate the heat out of the silicon. The mDFN4 PAD1 must
be connected to ground plane to increase the heat transfer if
necessary. By increasing PCB area, the R
q
JA
of the package
can be decreased, allowing higher power dissipation.
ORDERING INFORMATION
Device Marking Package Shipping
†
NCP330MUTBG 3A
UDFN4
(Pb−Free)
3000 / Tape & Reel
NCV330MUTBG* 3V
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
*NCV Prefix for Automotive and Other Applications Requiring Unique Site and Control Change Requirements; AEC−Q100 Qualified and PPAP
Capable.
