NX2119 Datasheet, PDF (1/16 Pages) Microsemi Corporation – SYNCHRONOUS PWM CONTROLLER WITH CURRENT LIMIT PROTECTION

Evaluation board available.
NX2119/2119A
SYNCHRONOUS PWM CONTROLLER WITH
CURRENT LIMIT PROTECTION
PRELIMINARY DATA SHEET
Pb Free Product
DESCRIPTION
FEATURES
The NX2119 controller IC is a synchronous Buck con- ^{n Bus voltage operation from 2V to 25V}
troller IC designed for step down DC to DC converter ^{n Fixed 300kHz and 600kHz}
applications. It is optimized to convert bus voltages from ^{n Internal Digital Soft Start Function}
2V to 25V to outputs as low as 0.8V voltage. The ^{n Prebias Startup}
NX2119 operates at fixed 300kHz, while NX2119A oper- ^{n Less than 50 nS adaptive deadband}
ates at fixed 600kHz, making it ideal for applications ^{n Current limit triggers latch out by sensing Rdson of}
requiring ceramic output capacitors. The NX2119 em- ^{Synchronous MOSFET}
ploys fixed loss-less current limiting by sensing the Rdson ^{n No negative spike at Vout during startup and}
of synchronous MOSFET followed by latch out feature. ^shutdown
Feedback under voltage triggers Hiccup.
n Pb-free and RoHS compliant
Other features of the device are: 5V gate drive, Adaptive
APPLICATIONS
deadband control, Internal digital soft start, Vcc n Graphic Card on board converters
undervoltage lock out and shutdown capability via the n Memory Vddq Supply
comp pin.
n On board DC to DC such as
12V to 3.3V, 2.5V or 1.8V
n ADSL Modem
TYPICAL APPLICATION
Vin
L2 1uH
+5V
C4
C5
100uF
R5
D1
1uF
10
MBR0530T1
Cin
280uF
18mohm
C3
1uF
5
1
Vcc BST
M3
HI=SD
R4
37.4k
7 _COMP
Hdrv ²
SW ⁸
C7
27pF
C2
2.2nF
6 _FB
Ldrv ⁴
Gnd
3
C6
0.1uF
M1
L1 1.5uH
M2
R1
4k
Vout
+1.8V 9A
Co
2 x (1500uF,13mohm)
R2
C1
4.7nF
10k
R3
8k
Figure1 - Typical application of 2119
ORDERING INFORMATION
Device
NX2119CSTR
NX2119ACSTR
NX2119ACUTR
Temperature
0 to 70^oC
0 to 70^o C
0 to 70^o C
Package
SOIC - 8L
SOIC - 8L
MSOP - 8L
Frequency
300kHz
600kHz
600kHz
Pb-Free
Yes
Yes
Yes
Rev.3.2
1
04/10/08