参数资料
型号: LM2798MMX-2.0/NOPB
厂商: NATIONAL SEMICONDUCTOR CORP
元件分类: 稳压器
英文描述: 0.12 A SWITCHED CAPACITOR REGULATOR, 500 kHz SWITCHING FREQ-MAX, PDSO10
封装: MSOP-10
文件页数: 1/14页
文件大小: 388K
代理商: LM2798MMX-2.0/NOPB
LM2797/LM2798
120mA High Efficiency Step-Down Switched Capacitor
Voltage Converter with Voltage Monitoring
General Description
The LM2797/98 switched capacitor step-down DC/DC con-
verters efficiently produce a 120mA regulated low-voltage
rail from a 2.6V to 5.5V input. Fixed output voltage options of
1.5V, 1.8V, and 2.0V are available. The LM2797/98 uses
multiple fractional gain configurations to maximize conver-
sion efficiency over the entire input voltage and output cur-
rent ranges. Also contributing to high overall efficiency is the
extremely low supply current of the LM2797/98: 35A oper-
ating unloaded and 0.1A in shutdown.
Features of the LM2797/98 include input voltage and output
voltage monitoring. Pin BATOK provides battery monitoring
by indicating when the input voltage is above 2.85V (typ.).
Pin POK verifies that the output voltage is not more than 5%
(typ.) below the nominal output voltage of the part.
The optimal external component requirements of the
LM2797/98 solution minimize size and cost, making the part
ideal for Li-Ion and other battery powered designs. Two 1F
flying capacitors and two 10F bypass capacitors are all that
is required, and no inductors are needed.
The LM2797/98 also features short-circuit protection over-
temperature protection, and soft-start circuitry to prevent
excessive inrush currents. The LM2798 has a 400s turn-on
time. The turn-on time of the LM2797 is 100s.
Features
n
Output voltage options:
2.0V ± 5%, 1.8V ± 5%, and 1.5V ± 6%
n
120mA output current capability
n
Multi-Gain and Gain Hopping for Highest Possible
Efficiency - up to 90% Efficient
n
2.6V to 5.5V input range
n
Input and Output Voltage Monitoring (BATOK and POK)
n
Low operating supply current: 35A
n
Shutdown supply current: 0.1A
n
Thermal and short circuit protection
n
LM2798 turn-on time: 400s
LM2797 turn-on time: 100s
n
Available in an 10-Pin MSOP Package
Applications
n
Cellular Phones
n
Pagers
n
H/PC and P/PC Devices
n
Portable Electronic Equipment
n
Handheld Instrumentation
Typical Application Circuit
20044501
April 2003
LM2797/LM2798
120mA
High
Efficiency
Step-Down
Switched
Capacitor
V
oltage
Converter
with
V
oltage
Monitoring
2003 National Semiconductor Corporation
DS200445
www.national.com
相关PDF资料
PDF描述
LM285AMX-1.2 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 1.235 V, PDSO8
LM385BSMX-1.2 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 1.235 V, PDSO8
LM385AYMX-1.2 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 1.235 V, PDSO8
LM385AMX-1.2 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 1.235 V, PDSO8
LM285AYMX-1.2 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 1.235 V, PDSO8
相关代理商/技术参数
参数描述
LM27A 制造商:NSC 制造商全称:National Semiconductor 功能描述:【3∑C Accurate, 120∑C-150∑C Factory Preset Thermostat (LM27 in Die Form)
LM27CIM5-1HJ 功能描述:恒温器 RoHS:否 制造商:Maxim Integrated 功能: 开路温度: 闭合温度: 准确性:+/- 1 C 温度范围:- 55 C to + 125 C 电流额定值:500 uA 电压额定值:2.7 V to 5.5 V 产品:Thermostats
LM27CIM5-1HJ/NOPB 功能描述:恒温器 RoHS:否 制造商:Maxim Integrated 功能: 开路温度: 闭合温度: 准确性:+/- 1 C 温度范围:- 55 C to + 125 C 电流额定值:500 uA 电压额定值:2.7 V to 5.5 V 产品:Thermostats
LM27CIM5-2HJ 功能描述:恒温器 RoHS:否 制造商:Maxim Integrated 功能: 开路温度: 闭合温度: 准确性:+/- 1 C 温度范围:- 55 C to + 125 C 电流额定值:500 uA 电压额定值:2.7 V to 5.5 V 产品:Thermostats
LM27CIM5-2HJ/NOPB 功能描述:恒温器 RoHS:否 制造商:Maxim Integrated 功能: 开路温度: 闭合温度: 准确性:+/- 1 C 温度范围:- 55 C to + 125 C 电流额定值:500 uA 电压额定值:2.7 V to 5.5 V 产品:Thermostats