LM2840

ACTIVE

SIMPLE SWITCHER® 42V, 100mA Step-Down DC/DC Regulator in Thin SOT-23

A newer version of this product is available

open-in-new Compare alternates
Pin-for-pin with same functionality to the compared device
LMR54406 ACTIVE SIMPLE SWITCHER® power converter with 4-V to 36-V input, 0.6-A, synchronous buck and 80-µA IQ Smaller footprint, lower quiescent current, FPWM and PFM options.

Product details

Rating Catalog Operating temperature range (°C) -40 to 125 Topology Buck Type Converter Iout (max) (A) 0.1 Vin (min) (V) 4.5 Vin (max) (V) 42 Switching frequency (min) (kHz) 950 Switching frequency (max) (kHz) 1500 Features Enable, Over Current Protection Control mode current mode Vout (min) (V) 0.765 Vout (max) (V) 34 Iq (typ) (µA) 1300 Duty cycle (max) (%) 94
Rating Catalog Operating temperature range (°C) -40 to 125 Topology Buck Type Converter Iout (max) (A) 0.1 Vin (min) (V) 4.5 Vin (max) (V) 42 Switching frequency (min) (kHz) 950 Switching frequency (max) (kHz) 1500 Features Enable, Over Current Protection Control mode current mode Vout (min) (V) 0.765 Vout (max) (V) 34 Iq (typ) (µA) 1300 Duty cycle (max) (%) 94
SOT-23-THN (DDC) 6 8.12 mm² 2.9 x 2.8
  • Input voltage 4.5 V to 42 V
  • Output current options of 100 mA, 300 mA, and 600 mA
  • Feedback pin voltage of 0.765 V
  • 550-kHz (X) or 1.25-MHz (Y) switching frequency
  • Low shutdown IQ: 16-µA typical
  • Short-circuit protected
  • Internally compensated
  • Soft-start circuitry
  • Small overall solution size (SOT-6L package)
  • Create a custom design using the LM2840 (or LM2841/42) with the WEBENCH® Power Designer
  • Input voltage 4.5 V to 42 V
  • Output current options of 100 mA, 300 mA, and 600 mA
  • Feedback pin voltage of 0.765 V
  • 550-kHz (X) or 1.25-MHz (Y) switching frequency
  • Low shutdown IQ: 16-µA typical
  • Short-circuit protected
  • Internally compensated
  • Soft-start circuitry
  • Small overall solution size (SOT-6L package)
  • Create a custom design using the LM2840 (or LM2841/42) with the WEBENCH® Power Designer

The LM284x SIMPLE SWITCHER™ devices are PWM DC/DC buck (step-down) regulators. With an input range from 4.5 V to 42 V, they are suitable for a wide range of applications, such as power conditioning from unregulated sources. They feature a low RDSON (0.9‑Ω typical) internal switch for maximum efficiency (85% typical). Operating frequency is fixed at 550 kHz (X option) and 1.25 MHz (Y option), allowing the use of small external components while still being able to have low output voltage ripple. Soft start can be implemented using the shutdown (SHDN) pin with an external RC circuit allowing the user to tailor the soft-start time to a specific application.

The LM2840 is optimized for up to 100 mA, the LM2841 for up to 300 mA, and the LM2842 for up to 600‑mA load currents. They all have a 0.765-V nominal feedback voltage.

Additional features include: thermal shutdown, VIN undervoltage lockout, and gate-drive undervoltage lockout. The LM284x are available in a low-profile SOT-6L package.

The LM284x SIMPLE SWITCHER™ devices are PWM DC/DC buck (step-down) regulators. With an input range from 4.5 V to 42 V, they are suitable for a wide range of applications, such as power conditioning from unregulated sources. They feature a low RDSON (0.9‑Ω typical) internal switch for maximum efficiency (85% typical). Operating frequency is fixed at 550 kHz (X option) and 1.25 MHz (Y option), allowing the use of small external components while still being able to have low output voltage ripple. Soft start can be implemented using the shutdown (SHDN) pin with an external RC circuit allowing the user to tailor the soft-start time to a specific application.

The LM2840 is optimized for up to 100 mA, the LM2841 for up to 300 mA, and the LM2842 for up to 600‑mA load currents. They all have a 0.765-V nominal feedback voltage.

Additional features include: thermal shutdown, VIN undervoltage lockout, and gate-drive undervoltage lockout. The LM284x are available in a low-profile SOT-6L package.

Download View video with transcript Video

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 15
Type Title Date
* Data sheet LM284x SIMPLE SWITCHER® 4.5-V to 42-V Input, 0.1-, 0.3-, or 0.6-A Output Step-Down DC/DC Regulator in Thin SOT datasheet (Rev. K) PDF | HTML 09 Apr 2019
Application note Semiconductor and IC Package Thermal Metrics (Rev. D) PDF | HTML 25 Mar 2024
Application note Low EMI Layout Made SIMPLE With LM43600/1/2/3 and LM46000/1/2 (Rev. A) 12 Sep 2014
Application note AN-2162 Simple Success With Conducted EMI From DC-DC Converters (Rev. C) 24 Apr 2013
Application note AN-1149 Layout Guidelines for Switching Power Supplies (Rev. C) 23 Apr 2013
Application note AN-1197 Selecting Inductors for Buck Converters (Rev. B) 23 Apr 2013
Application note AN-1229 SIMPLE SWITCHER PCB Layout Guidelines (Rev. C) 23 Apr 2013
Application note AN-1246 Stresses in Wide Input DC-DC Converters (Rev. C) 23 Apr 2013
Application note AN-1520 A Guide to Board Layout for Best Thermal Resistance for Exposed Packages (Rev. B) 23 Apr 2013
Application note AN-1566 Techniques for Thermal Analysis of Switching Power Supply Designs (Rev. A) 23 Apr 2013
Application note AN-1889 How to Measure the Loop Transfer Function of Power Supplies (Rev. A) 23 Apr 2013
Application note AN-2155 Layout Tips for EMI Reduction in DC/ DC Converters (Rev. A) 23 Apr 2013
Application note Input and Output Capacitor Selection 19 Sep 2005
More literature SEM1600 Topic 4: Constructing Your Power Supply – Layout Considerations 12 Jul 2005
Application note AN-643 EMI/RFI Board Design (Rev. B) 03 May 2004

Design & development

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

Simulation model

LM2840X TINA transient model

SNVM676.TSC (130 KB) - TINA-TI Reference Design
Simulation model

LM2840X TINA-TI transient model

SNVM677.ZIP (13 KB) - TINA-TI Spice Model
Simulation model

LM2840X-Q1 PSpice Transient Model

SNVM329.ZIP (115 KB) - PSpice Model
Simulation model

LM2840X-Q1 Unencrypted PSpice Transient Model

SNVMAL8.ZIP (2 KB) - PSpice Model
Simulation model

LM2840Y TINA transient Model

SNVM679.ZIP (14 KB) - TINA-TI Spice Model
Simulation model

LM2840Y TINA transient Reference Designs

SNVM678.TSC (609 KB) - TINA-TI Reference Design
Simulation model

LM2840Y-Q1 PSpice Transient Model

SNVM331.ZIP (111 KB) - PSpice Model
Simulation model

LM2840Y-Q1 Unencrypted PSpice Transient Model

SNVMAL7.ZIP (2 KB) - PSpice Model
Package Pins CAD symbols, footprints & 3D models
SOT-23-THN (DDC) 6 Ultra Librarian

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos