参数资料
型号: MAX1921
厂商: Maxim Integrated Products, Inc.
元件分类: DC/DC变换器
英文描述: Low-Voltage, 400mA Step-Down DC-DC Converters in SOT23
中文描述: 低电压、400mA、降压型DC-DC转换器,SOT23封装
文件页数: 1/9页
文件大小: 370K
代理商: MAX1921
General Description
The MAX1920/MAX1921 step-down converters deliver
over 400mA to outputs as low as 1.25V. These convert-
ers use a unique proprietary current-limited control
scheme that achieves over 90% efficiency. These
devices maintain extremely low quiescent supply current
(50μA), and their high 1.2MHz (max) operating frequency
permits small, low-cost external components. This combi-
nation makes the MAX1920/MAX1921 excellent high-
efficiency alternatives to linear regulators in space-
constrained applications.
Internal synchronous rectification greatly improves effi-
ciency and eliminates the external Schottky diode
required in conventional step-down converters. Both
devices also include internal digital soft-start to limit
input current upon startup and reduce input capacitor
requirements.
The MAX1920 provides an adjustable output voltage
(1.25V to 4V). The MAX1921 provides factory-preset
output voltages (see the
Selector Guide
). Both are
available in space-saving 6-pin SOT23 packages.
Applications
Next-Generation Wireless Handsets
PDAs, Palmtops, and Handy-Terminals
Battery-Powered Equipment
CDMA Power Amplifier Supply
Features
o
400mA Guaranteed Output Current
o
Internal Synchronous Rectifier for >90%
Efficiency
o
Tiny 6-Pin SOT23 Package
o
Up to 1.2MHz Switching Frequency for Small
External Components
o
50μA Quiescent Supply Current
o
0.1μA Logic-Controlled Shutdown
o
2V to 5.5V Input Range
o
Fixed 1.5V, 1.8V, 2.5V, 3V, and 3.3V Output
Voltages (MAX1921)
o
Adjustable Output Voltage (MAX1920)
o
±1.5% Initial Accuracy
o
Soft-Start Limits Startup Current
Note:
The MAX1921 offers five preset output voltage options.
See the Selector Guide, and then insert the proper designator
into the blanks above to complete the part number.
M
Low-Voltage, 400mA Step-Down
DC-DC Converters in SOT23
________________________________________________________________
Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
19-2296; Rev 1; 7/02
MAX1921
AGND
IN
SHDN
LX
PGND
OUT
OFF
ON
4.75k
5600pF
4.7
μ
F
4.7
μ
H
OUTPUT
1.5V UP TO 400mA
INPUT
2V TO 5.5V
C
IN
Typical Operating Circuit
PART
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
6 SOT23-6
6 SOT23-6
MAX1920
EUT-T
MAX1921
EUT_ _-T
Ordering Information
AGND
OUT (FB)
SHDN
1
6
LX
5
PGND
IN
MAX1920
MAX1921
SOT23-6
TOP VIEW
2
3
4
( ) ARE FOR MAX1920 ONLY
Pin Configuration
相关PDF资料
PDF描述
MAX1921EUT PLASTIC ENCAPSULATED DEVICES
MAX1920EUT-T Low-Voltage, 400mA Step-Down DC-DC Converters in SOT23
MAX1921EUT-T Low-Voltage, 400mA Step-Down DC-DC Converters in SOT23
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