®
SP6123/SP6123A
Ideal for 2A to 10A, Small Footprint, DC-DC Power Converters
Low Voltage, Synchronous Step-Down PWM Controller
■
Optimized for Single Supply, 3V - 5.5V Applications
8 BST
GL 1
■
High Efficiency: Greater Than 95% Possible
SP6123
7 GH
V
CC
2
■
Accurate Fixed 300kHz (SP6123) or 500kHz
6 SWN
GND 3
8 Pin NSOIC
(SP6123A) Frequency Operation
5 V
FB
COMP 4
■
Fast Transient Response
■
Internal Soft Start Circuit
Now Available in Lead Free Packaging
■
Accurate 0.8V Reference Allows Low Output
Voltages
APPLICATIONS
■
Resistor Programmable Output Voltage
■
DSP
■
Loss-less Current Limit with High Side R
DS(ON)
■
Microprocessor Core
Sensing
■
I/O & Logic
■
Hiccup Mode Current Limit Protection
■
Industrial Control
■
Dual N-Channel MOSFET Synchronous Driver
■
Distributed Power
■
Quiescent Current: 500µA, 30µA in Shutdown
■
8-Pin Surface Mount Package
■
Low Voltage Power
DESCRIPTION
The SP6123 is a fixed frequency, voltage mode, synchronous PWM controller designed to
work from a single 5V or 3.3V input supply, providing excellent AC and DC regulation for high
efficiency power conversion. Requiring only few external components, the SP6123 pack-
aged in an 8-pin NSOIC, is especially suited for low voltage applications where cost, small
size and high efficiency are critical. The operating frequency is internally set to 300kHz
(SP6123) or 500kHz (SP6123A), allowing small inductor values and minimizing PC board
space. The SP6123 drives an all N-channel synchronous power MOSFET stage for improved
efficiency and includes an accurate 0.8V reference for low output voltage applications.
TYPICAL APPLICATION CIRCUIT
3V to 5.5V
IN
MBR0530
V
IN
CB
2.2µF
GL
V
CC
GND
COMP
BST
GH
CBST
1µF
FDS6890A
L1
V
OUT
1.5µH
R1
10k
CP
56pF
RZ
15k
CC
4.7nF
FDS6890A
STPS2L25U
R2
10k
C
OUT1
470µF
C
OUT2
470µF
C
OUT3
1µF
C
IN
680µF
SP6123A
SWN
V
FB
0.8V to 5.0V
2A to 10A
(1.6V, 4A shown)
Date: 5/25/04
SP6123 Low Voltage, Synchronous Step Down PWM Controller
© Copyright 2004 Sipex Corporation
1
SIPEX [ SIPEX CORPORATION ]
