SP6123 Datasheet, PDF (1/18 Pages) Sipex Corporation – Low Voltage, Synchronous Step-Down PWM Controller Ideal for 2A to 10A, Small Footprint, DC-DC Power Converters

®
SP6123/SP6123A
Low Voltage, Synchronous Step-Down PWM Controller
Ideal for 2A to 10A, Small Footprint, DC-DC Power Converters
FEATURES
■ Optimized for Single Supply, 3V - 5.5V Applications
■ High Efficiency: Greater Than 95% Possible
■ Accurate Fixed 300kHz (SP6123) or 500kHz
(SP6123A) Frequency Operation
GL 1
VCC 2
GND 3
SP6123
8 Pin nSOIC
8 BST
7 GH
6 SWN
■ Fast Transient Response
COMP 4
5 VFB
■ Internal Soft Start Circuit
■ Accurate 0.8V Reference Allows Low Output ^{Now Available in Lead Free Packaging}
Voltages
APPLICATIONS
■ Resistor Programmable Output Voltage
■ DSP
■ Loss-less Current Limit with High Side R_DS(ON)
Sensing
■ Hiccup Mode Current Limit Protection
■ Microprocessor Core
■ I/O & Logic
■ Dual N-Channel MOSFET Synchronous Driver
■ Industrial Control
■ Quiescent Current: 500µA, 30µA in Shutdown
■ Distributed Power
■ 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
V_IN
CB
2.2µF
CP
56pF
GL
BST
V_{CC SP6123A}
GH
GND
SWN
COMP
V_FB
RZ
15k
CC
4.7nF
MBR0530
CBST
1µF
FDS6890A
L1
1.5µH
C_IN
680µF
3V to 5.5V
IN
R1
10k
C_OUT1
470µF
0.8V to 5.0V
2A to 10A
(1.6V, 4A shown)
V_OUT
C_OUT2
470µF
C_OUT3
1µF
FDS6890A
R2
10k
STPS2L25U
Date: 9/13/04
SP6123 Low Voltage, Synchronous Step Down PWM Controller
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© Copyright 2004 Sipex Corporation