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www.semtech.com
SC4625
1.7MHz High Efficiency Monolithic
0.5A Synchronous Buck Converter
POWER MANAGEMENT
SC4625 is a BiCMOS integrated FET, synchronous, 0.5A
step-down regulator. It operates at the typical switching
frequency of 1.7MHz and enables the user to choose a
very small and inexpensive external output inductor and
capacitor.
Fully internally compensated current-mode control loop
provides a fast transient response and ensures excellent
line and load regulation. The SC4625 operates from 2.5V
to 5.5V, features internal P-MOS and N-MOS power switches
and is implemented as a current-mode pulse-width-
modulated (PWM) control scheme.
Multiple modes of operation are available to achieve high
performance and efficiency and makes the SC4625 ideally
suited for electronic devices where size is at premium.
These modes are: PWM fixed frequency, synchronous and
asynchronous load dependent, pulse-skipping at very light
load, and low-dropout 100% duty cycle mode, by
continuously turning on the upper P-MOSFET.
Description
Features
Applications
Fully integrated MOSFET switches and compensation
1.7MHz fixed frequency operation
Input voltage range: 2.5V to 5.5V
Adjustable output voltage from 0.5V to V
IN
Pulse-skipping mode operation at light load
100% duty cycle in low-dropout mode
Over-temperature shutdown
MLP-10 lead free package. This product is fully WEEE
and RoHS compliant
-40C to +125C junction temperature range
WLAN and Bluetooth
applications
Distributed Power Systems
Micro DC-DC converters
USB-based DSL modems
Point-of-Load Regulation
FPGA Core and I/O Supplies
Set-top Boxes
Battery-powered devices (1 Li -Ion or 3 NiMh/NiCd)
Revision: November 30, 2005
Typical Application Circuit
L1
C3
+
_
Vin
Vout
C1
PH
1
VIN
2
NC
3
REG
7
NC
8
GND
9
GND
10
EN
5
FB
6
NC
4
U1
SC4625
R2
R1
C2
2
2005 Semtech Corp.
www.semtech.com
SC4625
POWER MANAGEMENT
Absolute Maximum Ratings
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Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified in
the Electrical Characteristics section is not implied.
Electrical Characteristics
Unless otherwise specified:
V
IN
= 3.3V, V
O
= 1.25V, I
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= 300mA; -40C
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4
2005 Semtech Corp.
www.semtech.com
SC4625
POWER MANAGEMENT
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Pin Configuration
Ordering Information
Notes:
(1) Only available in tape and reel packaging. A reel
contains 2500 devices.
(2) Lead free product. This product is fully WEEE and
RoHS compliant.
Pin Descriptions
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Top View
(MLP-10)
Marking Information
Top View
yyww = Datecode (Example: 0015)
xxxx = Semtech Lot No. (Example: 00101)
4625
yyww
xxxx
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