5.5 V to 30 V input, 300 kHz, synchronous DCAP2 mode dual step-down controller with LDO

LM2641 is not recommended for new designs
Although this product continues to be in production to support previous designs, we don't recommend it for new designs. Consider one of these alternates:
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Similar functionality to the compared device
NEW TPS56837 ACTIVE 4.5-V to 28-V input, 8-A synchronous buck converter Higher power density integrated FET converter solution for up to 8A output current

Product details

Vin (min) (V) 5.5 Vin (max) (V) 30 Iout (max) (A) 5 Operating temperature range (°C) 0 to 0 Control mode current mode Rating Catalog Vout (min) (V) 2.2 Vout (max) (V) 6 Iq (typ) (A) 0.0006 Duty cycle (max) (%) 98
Vin (min) (V) 5.5 Vin (max) (V) 30 Iout (max) (A) 5 Operating temperature range (°C) 0 to 0 Control mode current mode Rating Catalog Vout (min) (V) 2.2 Vout (max) (V) 6 Iq (typ) (A) 0.0006 Duty cycle (max) (%) 98
TSSOP (PW) 28 62.08 mm² 9.7 x 6.4
  • 300 kHz Fixed-Frequency Switching
  • Switching Synchronization with an External Signal up to 400 kHz
  • Optional Pulse-Skipping Mode
  • Adjustable Secondary Feedback
  • Input Undervoltage Lockout
  • Output Undervoltage Shutdown Protection
  • Output Overvoltage Shutdown Protection
  • Programmable Soft-Start (Each Controller)
  • 5V, 50 mA Linear Regulator Output
  • Precision 2.5V Reference Output
  • 28-pin TSSOP

Key Specifications

  • 96 % Efficient
  • 5.5 – 30 V Input Range
  • Dual Outputs Adjustable from 2.2 – 8 V
  • 0.5 % Typical Load Regulation Error
  • 0.002 %/V Typical Line Regulation Error

All trademarks are the property of their respective owners.

  • 300 kHz Fixed-Frequency Switching
  • Switching Synchronization with an External Signal up to 400 kHz
  • Optional Pulse-Skipping Mode
  • Adjustable Secondary Feedback
  • Input Undervoltage Lockout
  • Output Undervoltage Shutdown Protection
  • Output Overvoltage Shutdown Protection
  • Programmable Soft-Start (Each Controller)
  • 5V, 50 mA Linear Regulator Output
  • Precision 2.5V Reference Output
  • 28-pin TSSOP

Key Specifications

  • 96 % Efficient
  • 5.5 – 30 V Input Range
  • Dual Outputs Adjustable from 2.2 – 8 V
  • 0.5 % Typical Load Regulation Error
  • 0.002 %/V Typical Line Regulation Error

All trademarks are the property of their respective owners.

The LM2641 is a dual step-down power supply controller intended for application in notebook personal computers and other battery-powered equipment.

Fixed-frequency synchronous drive of logic-level N-channel power MOSFETs is combined with an optional pulse-skipping mode to achieve ultra efficient power conversion over a 1000:1 load current range. The pulse-skipping mode can be disabled in favor of fixed-frequency operation regardless of the load current level.

High DC gain and current-mode feedback control assure excellent line and load regulation and a wide loop bandwidth for fast response to dynamic loads.

An internal oscillator fixes the switching frequency at 300 kHz. Optionally, switching can be synchronized to an external clock running as fast as 400 kHz.

An optional soft-start feature limits current surges from the input power supply at start up and provides a simple means of start-up sequencing.

Logic-level inputs allow the controllers to be turned ON and OFF separately.

The LM2641 is a dual step-down power supply controller intended for application in notebook personal computers and other battery-powered equipment.

Fixed-frequency synchronous drive of logic-level N-channel power MOSFETs is combined with an optional pulse-skipping mode to achieve ultra efficient power conversion over a 1000:1 load current range. The pulse-skipping mode can be disabled in favor of fixed-frequency operation regardless of the load current level.

High DC gain and current-mode feedback control assure excellent line and load regulation and a wide loop bandwidth for fast response to dynamic loads.

An internal oscillator fixes the switching frequency at 300 kHz. Optionally, switching can be synchronized to an external clock running as fast as 400 kHz.

An optional soft-start feature limits current surges from the input power supply at start up and provides a simple means of start-up sequencing.

Logic-level inputs allow the controllers to be turned ON and OFF separately.

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* Data sheet LM2641 Dual Adjustable Step-Down Switching Power Supply Controller datasheet (Rev. B) 03 Apr 2013

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TSSOP (PW) 28 View options

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