SP6128A Datasheet, PDF (1/10 Pages) Sipex Corporation – Low Voltage, Synchronous Step Down PWM Controller Ideal for 2A to 10A, Small Footprint, DC-DC Power Converters

®
SP6128A
Low Voltage, Synchronous Step Down PWM Controller
Ideal for 2A to 10A, Small Footprint, DC-DC Power Converters
■ Optimized for Single Supply, 3V - 5.5V Applications GL 1
14 BST
■ High Efficiency: Greater Than 95% Possible
■ Discontinuous Startup for Precharged Output
■ Accurate Fixed 300kHz Frequency Operation
PV_CC 2
V_CC 3
PGND 4
SP6128A
14 pin TSSOP
13 GH
12 SWN
11 ISET
■ Fast Transient Response
GND 5
10 V_FB
■ Internal Soft Start Circuit
COMP 6
9 NC
■ Accurate 0.8V Reference Allows Low Output
NC 7
8 NC
Voltages
■ Resistor Programmable Output Voltage
Now Available in Lead Free Packaging
■ Resistor Programmable Overcurrent Threshold
■ Loss-less Current Limit with High Side R_DS(ON)
Sensing
■ Hiccup Mode Current Limit Protection
■ Dual N-Channel MOSFET Synchronous Driver
■ Quiescent Current: 500µA, 30µA in Shutdown
APPLICATIONS
■ DSP
■ Microprocessor Core
■ I/O & Logic
■ Industrial Control
■ Distributed Power
■ 14 pin TSSOP
■ Low Voltage Power
DESCRIPTION
The SP6128A 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 SP6128A pack-
aged in an 14-pin TSSOP, is especially suited for low voltage applications where cost, small
size and high efficiency are critical. The operating frequency is internally set to 300kHz,
allowing small inductor values and minimizing PC board space. The SP6128A drives two
N-channel power MOSFETs for improved efficiency and includes an accurate 0.8V reference
for low output voltage applications.
TYPICAL APPLICATION CIRCUIT
3V to 5.5V
D1
MBR0530
C5
10µF
C6
10µF
C7
10µF
R1
5
C1
2.2µF
1
GL
14
BST
2 _{PVCC SP6128A GH} 13
3 _VCC
12
SWN
4
PGND
11
ISET
5 _GND
VFB ¹⁰
6
COMP
9
NC
7
NC
NC ⁸
Q1
C4
R3 FDS6690A
8k
1µF
Q2
FDS6690A
C3
68pF
R2 7.87k C2 4.7n
L1 1.0µH
2.5V/10A
D2
STPS2L25U
C8
10µF
C9
10µF
C10 C11
10µF 470µF
R4
C12 1.7k
4.7nF
R5
800
Rev. 08/19/05
SP6128A Low Voltage, Synchronous Step Down PWM Controller
1
© Copyright 2005 Sipex Corporation