LM53603-Q1

ACTIVE

Automotive 3.5-V to 36-V, 3-A synchronous step-down converter

A newer version of this product is available

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This product continues to be available for existing customers. New designs should consider an alternate product.
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LMQ66430-Q1 ACTIVE Automotive 36-V, 3-A low EMI synchronous step-down converter with 1.5-µA IQ Integrated input bypass capacitor and boot cap for lower EMI and smaller footprint, dual-random spread spectrum and lower IQ.

Product details

Rating Automotive Operating temperature range (°C) -40 to 150 Topology Buck Type Converter Iout (max) (A) 3 Vin (min) (V) 3.5 Vin (max) (V) 42 Switching frequency (min) (kHz) 1850 Switching frequency (max) (kHz) 2350 Features Enable, Forced PWM, Frequency synchronization, Light Load Efficiency, Over Current Protection, Power good, Soft Start Fixed, Synchronous Rectification Control mode current mode Vout (min) (V) 3.2 Vout (max) (V) 9.9 Iq (typ) (µA) 23 Duty cycle (max) (%) 98
Rating Automotive Operating temperature range (°C) -40 to 150 Topology Buck Type Converter Iout (max) (A) 3 Vin (min) (V) 3.5 Vin (max) (V) 42 Switching frequency (min) (kHz) 1850 Switching frequency (max) (kHz) 2350 Features Enable, Forced PWM, Frequency synchronization, Light Load Efficiency, Over Current Protection, Power good, Soft Start Fixed, Synchronous Rectification Control mode current mode Vout (min) (V) 3.2 Vout (max) (V) 9.9 Iq (typ) (µA) 23 Duty cycle (max) (%) 98
HTSSOP (PWP) 16 32 mm² 5 x 6.4
  • The LM53603-Q1, LM53602-Q1 are available as
    AEC-Q1-Qualified Automotive Grade Products
    With Following Results:
    • Device Temperature Grade 1: –40°C to +125°C
      Ambient Operating Range
    • Device HBM ESD Classification Level 1C
    • Device CDM ESD Classification Level C4B
  • 3 A or 2 A maximum load current
  • Input Voltage Range from 3.5 V to 36 V:
    Transients to 42 V
  • Output Voltage Options: 5 V, 3.3 V, ADJ
  • 2.1 MHz Fixed Switching Frequency
  • ±2% Output Voltage Tolerance
  • –40°C to 150°C Junction Temperature Range
  • 1.7 µA Shutdown Current (typical)
  • 24 µA Input Supply Current at No Load (typical)
  • No external Feed-back Divider Required for 5 V or
    3.3 V output
  • Reset Output With Filter and Delay
  • Automatic Light Load Mode for Improved
    Efficiency
  • User-Selectable Forced PWM mode (FPWM)
  • Built-in Loop Compensation, Soft-start, Current
    Limit, Thermal Shutdown, UVLO, and External
    Frequency Synchronization
  • Thermally Enhanced 16-lead Package:
    5 mm × 4.4 mm × 1 mm
  • The LM53603-Q1, LM53602-Q1 are available as
    AEC-Q1-Qualified Automotive Grade Products
    With Following Results:
    • Device Temperature Grade 1: –40°C to +125°C
      Ambient Operating Range
    • Device HBM ESD Classification Level 1C
    • Device CDM ESD Classification Level C4B
  • 3 A or 2 A maximum load current
  • Input Voltage Range from 3.5 V to 36 V:
    Transients to 42 V
  • Output Voltage Options: 5 V, 3.3 V, ADJ
  • 2.1 MHz Fixed Switching Frequency
  • ±2% Output Voltage Tolerance
  • –40°C to 150°C Junction Temperature Range
  • 1.7 µA Shutdown Current (typical)
  • 24 µA Input Supply Current at No Load (typical)
  • No external Feed-back Divider Required for 5 V or
    3.3 V output
  • Reset Output With Filter and Delay
  • Automatic Light Load Mode for Improved
    Efficiency
  • User-Selectable Forced PWM mode (FPWM)
  • Built-in Loop Compensation, Soft-start, Current
    Limit, Thermal Shutdown, UVLO, and External
    Frequency Synchronization
  • Thermally Enhanced 16-lead Package:
    5 mm × 4.4 mm × 1 mm

The LM53603-Q1, LM53602-Q1 buck regulators are specifically designed for automotive applications, providing an output voltage of 5 V or 3.3 V (with ADJ option) at 3 A or 2 A, from an input voltage of up to 36 V. Advanced high-speed circuitry allows the device to regulate from an input of up to 20 V, while providing an output of 5 V at a switching frequency of 2.1 MHz. The innovative architecture allows the device to regulate a 3.3 V output from an input voltage of only 3.5 V. All aspects of this product are optimized for the automotive customer. An input voltage range up to 36 V, with transient tolerance up to 42 V, eases input surge protection design. An open drain reset output, with filtering and delay, provides a true indication of system status. This feature negates the requirement for an additional supervisory component, saving cost and board space. Seamless transition between PWM and PFM modes, along with a no-load operating current of only 24 µA, ensures high efficiency and superior transient response at all loads.

The LM53603-Q1, LM53602-Q1 buck regulators are specifically designed for automotive applications, providing an output voltage of 5 V or 3.3 V (with ADJ option) at 3 A or 2 A, from an input voltage of up to 36 V. Advanced high-speed circuitry allows the device to regulate from an input of up to 20 V, while providing an output of 5 V at a switching frequency of 2.1 MHz. The innovative architecture allows the device to regulate a 3.3 V output from an input voltage of only 3.5 V. All aspects of this product are optimized for the automotive customer. An input voltage range up to 36 V, with transient tolerance up to 42 V, eases input surge protection design. An open drain reset output, with filtering and delay, provides a true indication of system status. This feature negates the requirement for an additional supervisory component, saving cost and board space. Seamless transition between PWM and PFM modes, along with a no-load operating current of only 24 µA, ensures high efficiency and superior transient response at all loads.

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Similar products you might be interested in

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LM61430-Q1 ACTIVE Automotive 3-V to 36-V, 3-A, low-noise synchronous step-down converter Better electromagnetic compatibility (EMC), optimized for ultra-low EMI and smaller solution size.

Technical documentation

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Type Title Date
* Data sheet LM53603-Q1 (3 A), LM53602-Q1 (2 A) 3.5 V to 36 V Wide-VIN Synchronous 2.1 MHz Step-Down Converters for Automotive Applications datasheet (Rev. B) PDF | HTML 12 May 2016
Application note Design Consideration on Boot Resistor in Buck Converter PDF | HTML 15 May 2023
User guide Single LP8733-Q1 User's Guide to Power DRA78x and TDA3 (Rev. A) PDF | HTML 31 Mar 2021
Application note Designing High Performance, Low-EMI, Automotive Power Supplies 30 Sep 2017
EVM User's guide LM53602xEVM and LM53603xEVM User’s Guide (Rev. A) 23 May 2016
Technical article Overcoming automotive cluster power supply design challenges PDF | HTML 13 Nov 2015
Technical article How to overcome automotive front-end design challenges PDF | HTML 10 Sep 2015

Design & development

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

Evaluation board

LM536033EVM — Fixed Output 3.3V, 3A Buck Regulator Evaluation Module

The LM536033EVM demonstrates the capabilities of the LM53603 Automotive Integrated Buck regulator. It features all the input necessary to configure and operate the device. The EVM has an EMI filter on the back side. The user can choose to bypass that filter using the available posts close to the (...)
User guide: PDF
Not available on TI.com
Evaluation board

LM536035EVM — LM536035 5V Fixed Output, 3A Buck Regulator Evaluation Module

This EVM demonstrates the capabilities of the LM53603 Automotive Integrated Buck regulator. It features all the input necessary to configure and operate the device. The EVM has an EMI filter on the back side. The user can choose to bypass that filter using the available posts close to the converter.

User guide: PDF
Not available on TI.com
Evaluation board

LM53603AEVM — LM53603-Q1 Adjustable Output, 3A Buck Regulator Evaluation Module (EVM)

The LM53603AEVM demonstrates the capabilities of the LM53603 Automotive Integrated Buck regulator. It features all the input necessary to configure and operate the device. The EVM has an EMI filter on the back side. The user can choose to bypass that filter using the available posts close to the (...)
User guide: PDF
Not available on TI.com
Simulation model

LM53603 3P3 Unencrypted PSpice Transient Model

SNVMAC0.ZIP (7 KB) - PSpice Model
Simulation model

LM53603 3P3V PSpice Transient Model

SNVMA46.ZIP (72 KB) - PSpice Model
Simulation model

LM53603 5P0 Unencrypted PSpice Transient Model

SNVMAB9.ZIP (7 KB) - PSpice Model
Simulation model

LM53603 5V PSpice Transient Model

SNVMA56.ZIP (61 KB) - PSpice Model
Simulation model

LM53603 Adjustable PSpice Transient Model

SNVMA55.ZIP (62 KB) - PSpice Model
Simulation model

LM53603 Adjustable Unenecrypted PSpice Transient Model

SNVMAB8.ZIP (7 KB) - PSpice Model
Reference designs

PMP10604 — EMI Optimized 2-layer 15W Power Supply for Automotive with CISPR 25 Class 5 Compliance

The PMP10604 reference design is a 2-layer board 5V, 3A output power supply using LM53603 buck regulator for cluster unit in automotive applications. The LM53603 is a 3.5V to 36V input, 3A output capable, and 2.1 MHz fixed frequency buck regulator, specially designed for automotive applications. It (...)
Test report: PDF
Schematic: PDF
Reference designs

TIDA-01412 — Power Supply Reference Design for Automotive Microcontroller in Gateway and Body Control Module

This discrete power supply reference design demonstrates performance of the Freescale™ MPC5748G microcontroller. This reference design uses five DC/DC converters, it offers a more flexible and scalable design than when using a PMIC. It supports numerous automotive applications (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-00530 — Automotive Power Reference Design for Low Power TDA3x Based Systems

This solution was designed to make an integrated, size-optimized power design for ADAS applications using the TDA3x SoC off of an automotive battery input.  By targeting only applications with lower processing needs, we’re able to choose devices and components which are smaller, compared (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-00699 — Front End Power Supply Reference Design with Cold Crank Operation, Transient Protection, EMI Filter

This solution was designed to be a broadly applicable automotive off-battery front end power supply for 10-15W systems. There is a focus on EMI/EMC testing and compliance as well to help designers satisfy the regulatory requirements associated with producing an automotive electronic subsystem.
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-00745 — 15-W System-Level Power Reference Design for Automotive Body Control Module

TIDA-00745 is a 14-W system-optimized (CISPR25 Class 4) SMPS design for an automotive body control module. All buck converters used in this design are switching at 2.1 MHz. 

The design is divided into four major blocks:

  1. EMI filter: Common mode and a differential filter for conducted EMI suppression
  2. (...)
Design guide: PDF
Schematic: PDF
Reference designs

PMP10651 — 2.2MHz Switching, Synchronous Split Supply Reference Design for 12V Battery with all Protections

PMP10651 is a low noise, multi-output SMPS design where LM53603 is used in Inverting Buck-Boost Fly buck topology to generate positive and negative supply needed in multiple noise sensitive applications such as powering High Speed Video Amplifier, RF amplifier, Precision Low noise amplifier (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP10652 — System-Level Reference Design for 30W ADAS System With Required Automotive Protections

PMP10652 is a System optimized (CISPR 25 Class 3) 30W design for Surround View ADAS system.

The design has various protections such as Load dump through TVS (ISO pulse testing), Reverse Voltage (Innovative Smart diode with very low Iq), Battery Disconnect Switch with OVP protection (PFET) and is EMI (...)

Test report: PDF
Schematic: PDF
Reference designs

PMP10750 — System Level Power Reference Design for 20-W ADAS system with Automotive Protections

PMP10750 is a System optimized (CISPR 25 Class 5) 20W design for upstream converter used in ADAS system with automotive protection.

The design has various protections such as Load dump through TVS (ISO pulse testing), Reverse Voltage (Innovative Smart diode with very low Iq), Battery Disconnect (...)

Test report: PDF
Schematic: PDF
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HTSSOP (PWP) 16 Ultra Librarian

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