LM2679 SIMPLE SWITCHER® 8V to 40V, 5A Step-Down DC/DC Switching Regulator with Adjustable Current Limit | TI.com

LM2679
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SIMPLE SWITCHER® 8V to 40V, 5A Step-Down DC/DC Switching Regulator with Adjustable Current Limit

 

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  • LM43603  - The device has SIMILAR FUNCTIONALITY but is not functionally equivalent to the compared device.   Synchronous 36V, 3A Regulator - Higher efficiency, Low Quiescent Current, Smaller Solution Size

Description

The LM2679 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 5-A 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 3.3 V, 5 V, and 12 V 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 (260 kHz) allows the use of physically smaller sized components. A family of standard inductors for use with the LM2679 are available from several manufacturers to greatly simplify the design process.

Other features include the ability to reduce the input surge current at power on by adding a soft-start timing capacitor to gradually turn on the regulator. The LM2679 series also has built-in thermal shutdown and resistor programmable current limit of the power MOSFET switch to protect the device and load circuitry under fault conditions. The output voltage is specified to a ±2% tolerance. The clock frequency is controlled to within a ±11% tolerance.

Features

  • Efficiency Up to 92%
  • Simple and Easy to Design Using Off-The-Shelf
    External Components
  • Resistor Programmable Peak Current Limit Over a
    Range of 3 A to 7 A
  • 120-mΩ DMOS Output Switch
  • 3.3-V, 5-V, 12-V Fixed Output and Adjustable
    (1.2 V to 37 V) Versions
  • ±2% Maximum Output Tolerance Over Full Line
    and Load Conditions
  • Wide Input Voltage Range: 8 V to 40 V
  • 260-kHz Fixed Frequency Internal Oscillator
  • Soft-Start Capability
  • –40 to 125°C Operating Junction Temperature
    Range

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WEBENCH® Designer LM2679

  Min   Max Range
Vin  V 8.0 to 40.0V
Vout  V 1.21 to 40V
Iout  A ≤ 5A
Ambient Temp  °C -40 to 125°C

Parametrics

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Part number Order Vin (Min) (V) Vin (Max) (V) Vout (Min) (V) Vout (Max) (V) Iout (Max) (A) Regulated outputs (#) Switching frequency (Min) (kHz) Switching frequency (Max) (kHz) Iq (Typ) (mA) Features Control mode Duty cycle (Max) (%) Operating temperature range (C) Package Group Rating Type Package size: mm2:W x L (PKG)
LM2679 Order now 8     40     1.23     37     5     1     260     260     4.2     Adjustable Current Limit
Frequency Synchronization
Over Current Protection    
Voltage Mode     91     -40 to 125     DDPAK/TO-263 | 7
TO-220 | 7
VSON | 14    
Catalog     Converter     7DDPAK/TO-263: 154 mm2: 15.24 x 10.1 (DDPAK/TO-263 | 7)
7TO-220: 83 mm2: 8.13 x 10.16 (TO-220 | 7)
14VSON: 30 mm2: 5 x 6 (VSON | 14)    
LM2670 Order now 6.5     40     1.23     37     3     1     260     400     4.2     Frequency Synchronization
Over Current Protection    
Voltage Mode     91     -40 to 125     DDPAK/TO-263 | 7
TO-220 | 7
VSON | 14    
Catalog     Converter     7DDPAK/TO-263: 154 mm2: 15.24 x 10.1 (DDPAK/TO-263 | 7)
7TO-220: 83 mm2: 8.13 x 10.16 (TO-220 | 7)
14VSON: 30 mm2: 5 x 6 (VSON | 14)    
LM2671 Order now 6.5     40     1.23     37     0.5     1     225     400     2.5     Enable
Over Current Protection    
Voltage Mode     95     -40 to 125     PDIP | 8
SOIC | 8
WSON | 16    
Catalog     Converter     8PDIP: 93 mm2: 9.43 x 9.81 (PDIP | 8)
8SOIC: 19 mm2: 3.91 x 4.9 (SOIC | 8)
16WSON: 25 mm2: 5 x 5 (WSON | 16)    
LM2672 Order now 6.5     40     1.23     37     1     1     225     400     2.5     Enable
Over Current Protection    
Voltage Mode     95     -40 to 125     PDIP | 8
SOIC | 8
WSON | 16    
Catalog     Converter     8PDIP: 93 mm2: 9.43 x 9.81 (PDIP | 8)
8SOIC: 19 mm2: 3.91 x 4.9 (SOIC | 8)
16WSON: 25 mm2: 5 x 5 (WSON | 16)    
LM2673 Order now 8     40     1.23     37     3     1     260