NX2155H Datasheet, PDF (1/17 Pages) Microsemi Corporation – SINGLE POWER SUPPLY SYNCHRONOUS PWM CONTROLLER

NX2155H
SINGLE POWER SUPPLY SYNCHRONOUS PWM CONTROLLER
ADVANCED DATA SHEET
Pb Free Product
DESCRIPTION
FEATURES
The NX2155H controller IC is a single input supply syn- n Single supply voltage from 8V to 22V
chronous Buck controller IC designed for step down DC n Internal 5V regulator
to DC converter applications. NX2155H is optimized to n Programmable operational frequency of 2MHz
convert bus voltages from 8V to 22V to output as low as n Internal Digital Soft Start Function
0.8V voltage. An internal regulator converts bus voltage n Less than 50 nS adaptive deadband
to 5V, which provides voltage supply to internal logic n Current limit triggers hiccup by sensing Rdson of
and driver circuit. The NX2155H can operates at pro- Synchronous MOSFET
grammable frequency of 2MHz and employs loss-less n Pb-free and RoHS compliant
current limiting by sensing the Rdson of synchronous
MOSFET followed by hiccup feature.Feedback under _n
voltage triggers Hiccup.
n
Other features of the device are: Internal schottky di- _n
ode, thermal shutdown, 5V gate drive, adaptive _n
deadband control, internal digital soft start, 5VREG
undervoltage lock out and Shutdown capability via the _n
comp pin.
n
APPLICATIONS
LCD TV
Graphic Card on board converters
Memory Vddq Supply in mother board applications
On board DC to DC such as
12V to 3.3V, 2.5V or 1.8V
Hard Disk Drive
Set Top Box
TYPICAL APPLICATION
6 _VIN
0.1u
5 _5VREG
4.7u
4.22k _{7 RT}
8 _COMP
BST ³
0.1u
HDRV ²
SW ¹
OCP ^{10 6k}
LDRV ⁴
FB ⁹
10u
M1
AO6800
1u
300
180p
GND(PAD)
1n 15k
VIN
+12V
49.9k
9.53k
VOUT
+5V@2A
2 x (10uF,10V,X5R)
10p
Figure1 - Typical application of 2155H
ORDERING INFORMATION
Device
Temperature
Package
Package Marking
Pb-Free
NX2155HCUPTR 0 to 70^o C MSOP-EP-10L
NX155HXXX
Yes
Note: XXX is date code. For example, 841 means that this NX2155H is packaged in the 41th week of
2008
Rev.1.1
1
04/16/09