LM27402 3-20V, Voltage Mode Synchronous Buck Controller with DCR Current Sensing | TI.com

LM27402 (ACTIVE)

3-20V, Voltage Mode Synchronous Buck Controller with DCR Current Sensing

 

Description

The LM27402 is a voltage-mode, synchronous, DC/DC step-down controller with lossless inductor DCR current sensing capability. Sensing the inductor current eliminates the need to add resistive powertrain elements, which increases overall efficiency and facilitates accurate, continuous current sensing. A 0.6-V ±1% voltage reference enables high accuracy and low voltage capability at the output. An input operating voltage range of 3 V to 20 V makes the LM27402 suitable for a large variety of input rails.

The LM27402 voltage-mode control loop incorporates input voltage feed forward to maintain stability throughout the entire input-voltage range. The switching frequency is adjustable from 200 kHz to
1.2 MHz. Dual, high-current, integrated MOSFET drivers support large QG, low RDS(on) power MOSFETs. A power-good indicator provides power-rail-sequencing capability and output fault detection. An adjustable external soft start limits inrush current and provides monotonic output control during start-up. Other features include external tracking of other power supplies, integrated LDO bias supply, and synchronization capability.

Features

  • Wide Input-Voltage Range of 3 V to 20 V
  • Inductor DCR or Shunt Resistor Based Overcurrent Protection
  • 0.6-V Reference With ±1% FB Accuracy Across Full –40°C to 125°C Junction Temperature Range
  • Switching Frequency from 200 kHz to 1.2 MHz
  • Output Voltage as High as 95% of Input Voltage
  • Integrated High-Current MOSFET Drivers
  • Internal VDD Bias Supply LDO Subregulator
  • External Clock Synchronization
  • Adjustable Soft Start With External Capacitor
  • Prebiased Start-up Capability
  • Power Supply Tracking
  • Voltage-Mode Control With Line Feedforward
  • Open-Drain Power-Good Indicator
  • Precision Enable With Hysteresis
  • 16-Pin HTSSOP and WQFN Packages
  • Create a Custom Design Using the LM27402 With the WEBENCH® Power Designer

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WEBENCH® Designer LM27402

  Min   Max Range
Vin  V 3.0 to 20.0V
Vout  V 0.6 to 18.6V
Iout  A ≤ 30A
Ambient Temp  °C -40 to 125°C

Parametrics

Compare all products in Buck controllers (external switch) Email Download to Excel
Part number Order Vin (Min) (V) Vin (Max) (V) Vout (Min) (V) Vout (Max) (V) Iout (Max) (A) Regulated outputs (#) Number of Phases Switching frequency (Min) (kHz) Switching frequency (Max) (kHz) Iq (Typ) (mA) Features Duty cycle (Max) (%) Operating temperature range (C) Rating Package Group Type Control mode
LM27402 Order now 3     20     0.6     18.6     30     1     1     200     1200     4.5     Enable
Frequency Synchronization
Power Good
Pre-Bias Start-Up
Synchronous Rectification
Tracking    
95     -40 to 125     Catalog     HTSSOP | 16
WQFN | 16    
Controller     Voltage Mode    
LM2743 Order now 2.2     16     0.6     13.5     20     1     1     50     1000     1.5     Enable
Power Good
Synchronous Rectification
Tracking    
80     -40 to 125     Catalog     TSSOP | 14     Controller     Voltage Mode    
LM2745 Order now 1     14     0.6     12     20     1     1     250     1000     1.7     Enable
Frequency Synchronization
Power Good
Pre-Bias Start-Up
Synchronous Rectification
Tracking    
86     -40 to 125     Catalog     TSSOP | 14     Controller     Voltage Mode    
LM2747 Samples not available 1     14     0.6     12     20     1     1     50     1000     1.7     Enable
Frequency Synchronization
Power Good
Pre-Bias Start-Up
Synchronous Rectification
Tracking    
86     -40 to 125     Catalog     TSSOP | 14     Controller     Voltage Mode