SIMPLE SWITCHER High Efficiency 3A Step-Down Voltage Regulator with Sync - LM2670

LM2670 (ACTIVE)

SIMPLE SWITCHER High Efficiency 3A Step-Down Voltage Regulator with Sync

Recommended alternative parts

  • LM22670  -  Wider Input Voltage Range (4.5V To 42V), Adjustable Switching Frequency Up To 1MHz
  • LM22670-Q1  -  Wider Input Voltage Range (4.5V To 42V), Adjustable Switching Frequency Up To 1MHz
  • LM25576  -  For Ultra-Fast Transient Response
  • LM25576-Q1  -  For Ultra-Fast Transient Response
  • LM5576  -  Wider Input Voltage Range (6 To 75V) And Higher Switching Frequency (Up To 500kHz)
  • LM5576-Q1  -  Wider Input Voltage Range (6 To 75V) And Higher Switching Frequency (Up To 500kHz)

Description

The LM2670 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 output version.

The SIMPLE SWITCHER concept provides for a complete design using a minimum number of external components. The switching clock frequency can be provided by an internal fixed frequency oscillator (260KHz) or from an externally provided clock in the range of 280 kHz to 400 kHz which allows the use of physically smaller sized components. A family of standard inductors for use with the LM2670 are available from several manufacturers to greatly simplify the design process. The external Sync clock provides direct and precise control of the output ripple frequency for consistent filtering or frequency spectrum positioning.

The LM2670 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 ensured to a ±2% tolerance.

Features

  • Efficiency Up to 94%
  • Simple and Easy to Design with (Using Off-The-Shelf External Components)
  • 150 mΩ DMOS Output Switch
  • 3.3V, 5V and 12V Fixed Output and Adjustable (1.2V to 37V) Versions
  • 50μA Standby Current When Switched OFF
  • ±2% Maximum Output Tolerance Over Full Line and Load Conditions
  • Wide Input Voltage Range: 8V to 40V
  • External Sync Clock Capability (280kHz to 400kHz)
  • 260 kHz Fixed Frequency Internal Oscillator
  • −40 to +125°C Operating Junction Temperature Range

SIMPLE SWITCHER is a trademark of Texas Instruments. Switchers Made Simple is a trademark of Texas Instruments.

View more

Parametrics Compare all products in Step-Down (Buck) Converter

 
Regulated Outputs (#)
Vin (Min) (V)
Vin (Max) (V)
Vout (Min) (V)
Vout (Max) (V)
Iout (Max) (A)
Topology
Switching Frequency (Max) (kHz)
Switch Current Limit (Typ) (A)
Iq (Typ) (mA)
Duty Cycle (Max) (%)
Soft Start
Compensation
Special Features
Brand
Control Mode
Vref Accuracy (Typ) (%)
Rating
Operating Temperature Range (C)
Pin/Package
Approx. Price (US$)
LM2670 LM22670 LM22670-Q1 LM25576 LM25576-Q1 LM5576 LM5576-Q1
1     1     1     1     1     1     1    
6.5     4.5     4.5     6     6     6     6    
40     42     42     42     42     75     75    
1.23     1.285     1.285     1.23     1.23     1.23     1.23    
37     37     37     40     40     70     70    
3     3     3     3     3     3     3    
Buck     Buck     Buck     Buck     Buck     Buck     Buck    
400     1000     1000     1000     1000     500     500    
4.5     4.2     4.2     4.2     4.2     4.2     4.2    
4.2     3.4     3.4     1     1     1     1    
91     90     90     95     95     95     95    
Fixed     Fixed     Fixed     Adjustable     Adjustable     Adjustable     Adjustable    
Internal     Internal     Internal     External     External     External     External    
Enable     Enable     Enable     Enable
Tracking    
Enable     Enable
Tracking    
Enable    
SIMPLE SWITCHER     SIMPLE SWITCHER     SIMPLE SWITCHER     SIMPLE SWITCHER     SIMPLE SWITCHER     SIMPLE SWITCHER     SIMPLE SWITCHER    
Voltage Mode     Voltage Mode     Voltage Mode     Current Mode     Current Mode     Current Mode     Current Mode    
2     1.5     1.5     1.5     1.5     1.5     1.5    
Catalog     Catalog     Automotive     Catalog     Automotive     Catalog     Automotive    
-40 to 125     -40 to 125     -40 to 125     -40 to 125     -40 to 125     -40 to 125     -40 to 125    
14VSON
7DDPAK/TO-263
7TO-220    
7TO-263
8SO PowerPAD    
7TO-263
8SO PowerPAD    
20HTSSOP     20HTSSOP     20HTSSOP     20HTSSOP    
1.85 | 1ku     1.85 | 1ku     1.95 | 1ku     2.00 | 1ku     2.30 | 1ku     2.60 | 1ku     3.15 | 1ku    

Related end equipment

  • Simple to Design, High Efficiency (>90%) Step-Down Switching Regulators
  • Efficient System Pre-Regulator for Linear Voltage Regulators
  • Battery Chargers
  • Communications and Radio Equipment Regulator with Synchronized Clock Frequency

Featured tools and software

WEBENCH® LM2670
    Min   Max   Range  
  Vin V    8.00 – 40.00V  
  Vout V    1.21 – 40.00V  
  Iout A    ≤ 3.00A  
  Ambient Temp °C    ≤ 100°C  
Footprint BOM Cost Efficiency
 
 
 
'IC Cinx Cb Rsync Csync Rfb1 Rfb2 D1 L1 Cout Cin '
 
What are WEBENCH® tools?
Click Here