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LM25117

ACTIVE

4.5-42V Wide Vin, Current Mode Synchronous Buck Controller with Tracking

A newer version of this product is available

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Same functionality with different pin-out to the compared device
LM25149 ACTIVE 42-V synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter Active EMI filtering and DRSS reduces EMI by an average of 25 dBµV.

Product details

Vin (min) (V) 4.5 Vin (max) (V) 42 Vout (min) (V) 0.8 Vout (max) (V) 41 Iout (max) (A) 20 Iq (typ) (mA) 4.8 Switching frequency (min) (kHz) 50 Switching frequency (max) (kHz) 750 Features Adjustable current limit, Enable, Frequency synchronization, Light Load Efficiency, Synchronous Rectification, Tracking, UVLO adjustable Operating temperature range (°C) -40 to 125 Regulated outputs (#) 1 Number of phases 1 Rating Catalog Control mode current mode Type Controller
Vin (min) (V) 4.5 Vin (max) (V) 42 Vout (min) (V) 0.8 Vout (max) (V) 41 Iout (max) (A) 20 Iq (typ) (mA) 4.8 Switching frequency (min) (kHz) 50 Switching frequency (max) (kHz) 750 Features Adjustable current limit, Enable, Frequency synchronization, Light Load Efficiency, Synchronous Rectification, Tracking, UVLO adjustable Operating temperature range (°C) -40 to 125 Regulated outputs (#) 1 Number of phases 1 Rating Catalog Control mode current mode Type Controller
HTSSOP (PWP) 20 41.6 mm² 6.5 x 6.4 WQFN (RTW) 24 16 mm² 4 x 4
  • LM25117-Q1 is Qualified for Automotive Applications
  • AEC-Q100 Qualified With the Following Results:
    • Device Temperature Grade 1: -40°C to 125°C Ambient Operating Temperature Range
  • Emulated Peak Current Mode Control
  • Wide Operating Range from 4.5 V to 42 V
  • Robust 3.3 A Peak Gate Drives
  • Adaptive Dead-time Output Driver Control
  • Free-run or Synchronizable Clock up to 750 kHz
  • Optional Diode Emulation Mode
  • Programmable Output from 0.8 V
  • Precision 1.5% Voltage Reference
  • Analog Current Monitor
  • Programmable Current Limit
  • Hiccup Mode Over Current Protection
  • Programmable Soft-start and Tracking
  • Programmable Line Undervoltage Lockout
  • Programmable Switch-over to External Bias Supply
  • Thermal Shutdown
  • LM25117-Q1 is Qualified for Automotive Applications
  • AEC-Q100 Qualified With the Following Results:
    • Device Temperature Grade 1: -40°C to 125°C Ambient Operating Temperature Range
  • Emulated Peak Current Mode Control
  • Wide Operating Range from 4.5 V to 42 V
  • Robust 3.3 A Peak Gate Drives
  • Adaptive Dead-time Output Driver Control
  • Free-run or Synchronizable Clock up to 750 kHz
  • Optional Diode Emulation Mode
  • Programmable Output from 0.8 V
  • Precision 1.5% Voltage Reference
  • Analog Current Monitor
  • Programmable Current Limit
  • Hiccup Mode Over Current Protection
  • Programmable Soft-start and Tracking
  • Programmable Line Undervoltage Lockout
  • Programmable Switch-over to External Bias Supply
  • Thermal Shutdown

The LM25117 is a synchronous buck controller intended for step-down regulator applications from a high voltage or widely varying input supply. The control method is based upon current mode control utilizing an emulated current ramp. Current mode control provides inherent line feed-forward, cycle-by-cycle current limiting and ease of loop compensation. The use of an emulated control ramp reduces noise sensitivity of the pulse-width modulation circuit, allowing reliable control of very small duty cycles necessary in high input voltage applications.

The operating frequency is programmable from 50 kHz to 750 kHz. The LM25117 drives external high-side and low-side NMOS power switches with adaptive dead-time control. A user-selectable diode emulation mode enables discontinuous mode operation for improved efficiency at light load conditions. A high voltage bias regulator that allows external bias supply further improves efficiency. The LM25117’s unique analog telemetry feature provides average output current information. Additional features include thermal shutdown, frequency synchronization, hiccup mode current limit and adjustable line undervoltage lockout.

The LM25117 is a synchronous buck controller intended for step-down regulator applications from a high voltage or widely varying input supply. The control method is based upon current mode control utilizing an emulated current ramp. Current mode control provides inherent line feed-forward, cycle-by-cycle current limiting and ease of loop compensation. The use of an emulated control ramp reduces noise sensitivity of the pulse-width modulation circuit, allowing reliable control of very small duty cycles necessary in high input voltage applications.

The operating frequency is programmable from 50 kHz to 750 kHz. The LM25117 drives external high-side and low-side NMOS power switches with adaptive dead-time control. A user-selectable diode emulation mode enables discontinuous mode operation for improved efficiency at light load conditions. A high voltage bias regulator that allows external bias supply further improves efficiency. The LM25117’s unique analog telemetry feature provides average output current information. Additional features include thermal shutdown, frequency synchronization, hiccup mode current limit and adjustable line undervoltage lockout.

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Technical documentation

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

LM25117EVAL — LM25117 Wide Vin Synchronous Buck Controller Evaluation Board

The LM25117 evaluation board provides the design engineer with a fully functional synchronous buck converter based on Emulated Current Mode Control to evaluate the LM25117 controller IC. The evaluation board provides 3.3V output with a 9A current capability in addition with average output current (...)

User guide: PDF
Not available on TI.com
Simulation model

LM25117 PSpice Average Model

SNVM385.ZIP (51 KB) - PSpice Model
Simulation model

LM25117 PSpice Transient Model (Rev. A)

SNVM386A.ZIP (167 KB) - PSpice Model
Simulation model

LM25117 TINA-TI Average Reference Design (Rev. A)

SNVM488A.TSC (148 KB) - TINA-TI Reference Design
Simulation model

LM25117 TINA-TI Average Spice Model (Rev. A)

SNVM489A.ZIP (8 KB) - TINA-TI Spice Model
Simulation model

LM25117 TINA-TI Transient Reference Design(Load transient)

SNVM490.TSC (196 KB) - TINA-TI Reference Design
Simulation model

LM25117 TINA-TI Transient Reference Design(START UP)

SNVM491.TSC (226 KB) - TINA-TI Reference Design
Simulation model

LM25117 TINA-TI Transient Spice Model

SNVM492.ZIP (19 KB) - TINA-TI Spice Model
Simulation model

LM25117 Unencrypted PSpice Average Model

SNVM864.ZIP (2 KB) - PSpice Model
Simulation model

LM25117 Unencrypted PSpice Transient Model

SNVM860.ZIP (6 KB) - PSpice Model
Calculation tool

LM25117-5117QUICK-CALC — LM(2)5117 Quick Start Calculator

Simulation tool

PSPICE-FOR-TI — PSpice® for TI design and simulation tool

PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
Reference designs

PMP11114 — Automotive Input Dual Port USB Type C Charger Reference Design

PMP11114 is a dual port USB Type C Charger. This design takes an automotive input voltage (7V to 18V nominal, load dump to 40V).  The output goes to two USB Type ports, each of these ports supplies 5V.  The desgin supports 3A on one port and 1.5A on the other port.  The DC/DC portion (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP10509 — 432W High-Efficiency Single-Phase Synchronous Buck Converter Reference Design

PMP10509 is a High-Efficiency Single-Phase Synchronous Buck Converter using the LM25117 controller IC. The design accepts an input voltage of 30.4Vin to 33.6Vin (32Vin Nominal) and provides an output of 24Vout capable of supplying 18A of continuous current to the load.
Test report: PDF
Schematic: PDF
Reference designs

PMP10514 — 300W High-Efficiency Single-Phase Synchronous Buck Converter Reference Design

PMP10514 is a High-Efficiency Single-Phase Synchronous Buck Converter using the LM25117 controller IC. The design accepts an input voltage of 30.4Vin to 33.6Vin (32Vin Nominal) and provides an output of 20 Vout capable of supplying 15A of continuous current to the load.
Test report: PDF
Schematic: PDF
Package Pins Download
HTSSOP (PWP) 20 View options
WQFN (RTW) 24 View options

Ordering & quality

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