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LM2676 SIMPLE SWITCHER High Efficiency 3A Step-Down Voltage Regulator

LM2676 特性Features
LM2676 概述Description

The LM2676 series of regulators are monolithic integrated circuits which provide all of the active functions for a step-down (buck) switching regulator capable of driving up to 3A loads with excellent line and load regulation characteristics. High efficiency (>90%) is obtained through the use of a low ON-resistance DMOS power switch. The series consists of fixed output voltages of 3.3V, 5V and 12V and an adjustable output version.

The SIMPLE SWITCHER concept provides for a complete design using a minimum number of external components. A high fixed frequency oscillator (260KHz) allows the use of physically smaller sized components. A family of standard inductors for use with the LM2676 are available from several manufacturers to greatly simplify the design process.

The LM2676 series also has built in thermal shutdown, current limiting and an ON/OFF control input that can power down the regulator to a low 50μA quiescent current standby condition. The output voltage is guaranteed to a ±2% tolerance. The clock frequency is controlled to within a ±11% tolerance.

LM2676 应用领域Applications
LM2676 典型性能Typical Application

LM2676 典型性能Typica Performance

LM2676 典型性能Typical Application

LM2676 功能框图Block Diagram

LM2676 功能框图Block Diagram

LM2676 典型性能Typical Performance

LM2676 典型性能Typical Performance
LM2676 性能参数Parametrics
Paramaters / Values LM2676 LM22676 LM25576 LM5576
Output Current 3000 mA 3000 mA 3000 mA 3000 mA
Input Min Voltage 15, 8 Volt 4.5 Volt 6 Volt 6 Volt
Input Max Voltage 40 Volt 42 Volt 42 Volt 75 Volt
Output Min 3.3, 1.23, 12, 5 Volt 1.285 Volt 1.23 Volt 1.23 Volt
Output Max 3.3, 12, 37, 5 Volt 40 Volt 70 Volt
Frequency Min 260 kHz 50 kHz 50 kHz
Frequency Max 260 kHz 1000 kHz 500 kHz
Efficiency (peak) 94, 88, 86 % 92 % 91 % 88 %
On/Off Pin Yes Yes Yes Yes
PowerGood / Error Flag No No No No
SoftStart No No Yes Yes
Sync Pin No No Yes Yes
Flyback No No No No
RegType Switching Regulator Switching Regulator Switching Regulator Switching Regulator
Temperature Min -40 deg C -40 deg C -40 deg C -40 deg C
Temperature Max 125 deg C 125 deg C 125 deg C 125 deg C
Adjustable Output Yes, No Yes Yes Yes
Adj Switch Frequency No No Yes Yes
PWM Mode Voltage with Vin Feedforward Voltage Mode Control Current Current
Topology Buck Buck Buck Buck
Special Features Internal Type 3 compensation, 2% output voltage accuracy, SIMPLE SWITCHER regulator 500 kHz Switching Frequency 1.5% feedback voltage accuracy, emulated current mode 1.5% feedback voltage accuracy, emulated current mode
Step-Down Yes Yes Yes Yes
Multiple Output Capability No No No No
Output Power Undefined Watt Undefined Watt Undefined Watt
Output Voltage 3.3, 12, Undefined, 5 Volt Undefined Volt Undefined Volt
Output Range 12V, 1.23V to 37V, 3.3V, 5V 1.23V to 37V 1.23V to 70V
Switching Frequency 260 kHz 500 kHz 1000 kHz 500 kHz
Regulator Family SIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER
Synchronous Rectification No No No No
LM2676 芯片订购型号
Part Number(s) (NSID) Top View Availability Budgetary Pricing Pack Size
LM2676S-12/NOPB
LM2676S-12

TO-263
Full production
Lead Time: 16 weeks
$1.92 each at 1K+ pcs reel of 45
LM2676S-3.3/NOPB
LM2676S-3.3

TO-263
Full production
Lead Time: 16 weeks
$1.92 each at 1K+ pcs reel of 45
LM2676S-5.0/NOPB
LM2676S-5.0

TO-263
Full production
Lead Time: 6 weeks
$1.92 each at 1K+ pcs reel of 45
LM2676S-ADJ/NOPB
LM2676S-ADJ

TO-263
Full production
Lead Time: 14 weeks
$1.92 each at 1K+ pcs reel of 45
LM2676SD-12/NOPB
LM2676SD-12

LLP
Full production
Lead Time: 6 weeks
$1.92 each at 1K+ pcs reel of 250
LM2676SD-3.3/NOPB
LM2676SD-3.3

LLP
Full production
Lead Time: 6 weeks
$1.92 each at 1K+ pcs reel of 250
LM2676SD-5.0/NOPB
LM2676SD-5.0

LLP
Full production
Lead Time: 12 weeks
$1.92 each at 1K+ pcs reel of 250
LM2676SD-ADJ/NOPB
LM2676SD-ADJ

LLP
Full production
Lead Time: 14 weeks
$1.92 each at 1K+ pcs reel of 250
LM2676SDX-12/NOPB
LM2676SDX-12

LLP
Full production
Lead Time: 6 weeks  
$1.92 each at 1K+ pcs reel of 2500
LM2676SDX-3.3/NOPB
LLP
Full production
Lead Time: 16 weeks  
$1.92 each at 1K+ pcs reel of 2500
LM2676SDX-5.0/NOPB
LM2676SDX-5.0

LLP
Full production
Lead Time: 6 weeks  
$1.92 each at 1K+ pcs reel of 2500
LM2676SDX-ADJ/NOPB
LM2676SDX-ADJ

LLP
Full production
Lead Time: 14 weeks  
$1.92 each at 1K+ pcs reel of 2500
LM2676SX-12/NOPB
LM2676SX-12

TO-263
Full production
Lead Time: 6 weeks  
$1.92 each at 1K+ pcs reel of 500
LM2676SX-3.3/NOPB
LM2676SX-3.3

TO-263
Full production
Lead Time: 10 weeks  
$1.92 each at 1K+ pcs reel of 500
LM2676SX-5.0/NOPB
LM2676SX-5.0

TO-263
Full production
Lead Time: 6 weeks  
$1.92 each at 1K+ pcs reel of 500
LM2676SX-ADJ/NOPB
LM2676SX-ADJ

TO-263
Full production
Lead Time: 10 weeks  
$1.92 each at 1K+ pcs reel of 500
LM2676T-12/NOPB
LM2676T-12

TO-220
Full production
Lead Time: 16 weeks
$1.92 each at 1K+ pcs rail of 45
LM2676T-3.3/NOPB
LM2676T-3.3

TO-220
Full production
Lead Time: 6 weeks
$1.92 each at 1K+ pcs rail of 45
LM2676T-5.0/NOPB
LM2676T-5.0

TO-220
Full production
Lead Time: 16 weeks
$1.92 each at 1K+ pcs rail of 45
LM2676T-ADJ/NOPB
LM2676T-ADJ

TO-220
Full production
Lead Time: 16 weeks
$1.92 each at 1K+ pcs rail of 45
LM2676 停产Obsolete Versions
Obsolete Part Alternate Part or Supplier Source Last Time Buy Date
LM2676D-12 NONE NONE 30-Jan-04
LM2676LD-3.3 NONE NONE 30-Jan-04
LM2676LD-5.0 NONE NONE 30-Jan-04
LM2676LD-ADJ NONE NONE 30-Jan-04
LM2676LDX-12 NONE NONE 30-Jan-04
LM2676LDX-3.3 NONE NONE 30-Jan-04
LM2676LDX-5.0 NONE NONE 30-Jan-04
LM2676LDX-ADJ NONE NONE 30-Jan-04
LM2676S-5.0EP NONE NATIONAL SEMICONDUCTOR 16-Nov-08
LM2676 应用技术支持与电子电路设计开发资源下载 Documents