4.5V to 14V Input, 15A Synchronous Step-Down SWIFT™ Converter - TPS56121


4.5V to 14V Input, 15A Synchronous Step-Down SWIFT™ Converter


TPS56121 is a high-efficiency and high-current synchronous buck converter designed to operate from a supply between 4.5 V and 14 V. The device is capable of producing an output voltage as low as 0.6 V at loads up to 25 A. Integrated NexFET™ Power MOSFETs provide a small footprint and ease of use.

The device implements a voltage-mode control with voltage feed-forward compensation that responds instantly to input voltage change.

TPS56121 is available in a thermally enhanced 22-pin PQFN (DQP) PowerPAD™ package.

The device offers design flexibility with a variety of user programmable functions, including soft-start, overcurrent protection (OCP) levels, and loop compensation. OCP levels are programmed by a single external resistor connected from the ILIM pin to the circuit ground. During the initial power-on sequence, the device enters a calibration cycle, measures the voltage at the ILIM pin, and sets an internal OCP voltage level. During operation, the programmed OCP voltage level is compared to the voltage drop across the low-side FET when it is on to determine whether there is an overcurrent condition. It then enters a shutdown/restart cycle until the fault is removed.


  • 4.5-V to 14-V Input Voltage Range
  • Incorporates Power Block Technology
  • Up to 25-A Output Current
  • Fixed Frequency Options of 300 kHz, 500 kHz and 1 MHz
  • High-Side and Low-Side MOSFET RDS(on) Sensing
  • Programmable Soft-Start
  • 600-mV Reference Voltage with 1% Accuracy
  • Voltage Mode Control with Feed-Forward
  • Supports Pre-Biased Output
  • Thermal Shutdown
  • 22-Pin 5 mm x 6 mm PQFN PowerPAD Package
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    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)
    Switching Frequency (Max) (kHz)
    Switch Current Limit (Typ) (A)
    Iq (Typ) (mA)
    Duty Cycle (Max) (%)
    Soft Start
    Special Features
    Control Mode
    Vref Accuracy (Typ) (%)
    Operating Temperature Range (C)
    Approx. Price (US$)
    TPS56121 TPS56221
    1     1    
    4.5     4.5    
    14     14    
    0.6     0.6    
    12     12    
    15     25    
    Buck     Buck    
    1000     1000    
    21     35    
    2.5     2.5    
    93     93    
    Adjustable     Adjustable    
    External     External    
    Power Good
    Adjustable Current Limit
    Synchronous Rectification    
    Light Load Efficiency
    Synchronous Rectification    
    SWIFT     SWIFT    
    Voltage Mode     Voltage Mode    
    1     1    
    Catalog     Catalog    
    -40 to 125     -40 to 125    
    22LSON-CLIP     22LSON-CLIP    
    3.50 | 1ku     3.75 | 1ku    
    WEBENCH® TPS56121
        Min   Max   Range  
      Vin V    4.50 – 14.00V  
      Vout V    0.60 – 12.00V  
      Iout A    ≤ 15A  
      Ambient Temp °C    ≤ 125°C  
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