IRU3034CSTR Datasheet, PDF (1/12 Pages) International Rectifier – 8-PIN PWM SWITCHER CONTROLLER IC WITH CURRENT LIMITING

Data Sheet No. PD94148 revA
IRU3034 & (PbF)
8-PIN PWM SWITCHER CONTROLLER IC
WITH CURRENT LIMITING
FEATURES
8-Pin SOIC switching controller with
HICCUP current limiting reduces diode power
dissipation to less than 1% of normal operation
Soft-Start capacitor allows for smooth output
voltage ramp up
On-Board MOSFET Driver
Fastest transient response of any controller
method. (0 to 100% Duty Cycle in 100ns)
1% Internal Voltage Reference
Internal Under-Voltage Lockout protects MOSFET
during start-up
APPLICATIONS
Dual supply low voltage processor applications,
such as: P55C, CYRIX M2, POWER PC
and AMD K6
Simple 5V to 3.3V switcher for Pentium with AGP
or Pentium II applications
TYPICAL APPLICATION
DESCRIPTION
The IRU3034 IC provides a low cost switching controller
with true short circuit protection all in a compact 8-pin
surface mount package, providing a low cost switching
solution for dual supply processor applications that re-
quire switching regulator for the 3.3V supply such as
the applications with AGP on-board. Typically in these
applications, a dual supply regulator converts 5V to 3.3V
for I/O supply and a jumper programmable supply of
1.25V to 3.5V for Core supply. The IC uses an internal
regulator generated from the 12V supply to power the
controller as well as the 12V supply to drive the power
MOSFET, allowing a low cost N-channel MOSFET to be
used. The IC also includes an error comparator for fast
transient response, a precise voltage reference for set-
ting the output voltage as well as a direct drive of the
MOSFET for the minimum part count.
12V
5V
C8
R1
SS CS+ CS-
Drv IRU3034 Gnd
V12 VFB VHYST
C3
R3
L1
Q2
C4
C1
C2
R2
C5
D1
C6
R8
R7
L2
R6
R4
VOUT
C7
R5
Figure 1 - Typical application of IRU3034.
Notes: P55C, Pentium II are trademarks of Intel Corp. K5 & K6 are trademarks of AMD corp. Cyrix 6X86L, M1, M2 are trademarks of Cyrix
Corp. Power PC is trademark of IBM Corp.
PACKAGE ORDER INFORMATION
TA (°C)
0 To 70
Basic Device Leadfree Device
IRU3034CS IRU3034CS(PbF)
Package
Parts per
Tube
8-Pin Plastic SOIC(S) 95
Parts per
Reel
2500
T&R
Orientation
see
Fig. A
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