High efficiency over a 1.5A to milliamperes load range
4V to 14V input voltage range
1.8V, 2.5V, 3.3V, or ADJ output voltage
Internal MOSFET switch with low RDS(on) of 75m
300kHz fixed frequency internal oscillator
7µA shutdown current
Patented current sensing for current mode control
Input undervoltage lockout
Adjustable soft-start
Current limit and thermal shutdown
16-pin TSSOP package
Description
The LM2651 switching regulator provides high efficiency power conversion over a 100:1 load range (1.5A to 15mA). This feature makes the LM2651 an ideal fit in battery-powered applications that demand long battery life in both run and standby modes.
Synchronous rectification is used to achieve up to 97% efficiency. At light loads, the LM2651 enters a low power hysteretic or "sleep" mode to keep the efficiency high. In many applications, the efficiency still exceeds 80% at 15mA load. A shutdown pin is available to disable the LM2651 and reduce the supply current to less than 10µA.
The LM2651 contains a patented current sensing circuitry for current mode control. This feature eliminates the external current sensing resistor required by other current-mode DC-DC converters.
The LM2651 has a 300 kHz fixed frequency internal oscillator. The high oscillator frequency allows the use of extremely small, low profile components.
A programmable soft-start feature limits current surges from the input power supply at start up and provides a simple means of sequencing multiple power supplies.
Other protection features include input undervoltage lockout, current limiting, and thermal shutdown.
1.5A High Efficiency Synchronous Switching Regulator
Features:
Ultra high efficiency up to 97%.
High efficiency over a 1.5A to milliamperes load range
4V to 14V input voltage range
1.8V, 2.5V, 3.3V, or Adj output voltage
Internal MOSFET switch with low RDS(on) of 75mW
300kHz fixed frequency internal oscillator
7mA shutdown current
Patented current sensing for current mode control
Input undervoltage lockout
Adjustable soft-start
Current limit and thermal shutdown
16-pin TSSOP package
Contents:
A fully assembled step-down DC/DC converter Evaluation board using LM2651-ADJ, Set for a 1.8V, 2.5V, 3.3V Output (Use R1/R2 to select voltage. Requires resistors to change the voltage).
Evaluation board Application Note
Power Management CD
Datasheets for similar synchronous converters
Simple Switcher® selection guide
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and Banned Substances and Materials of Interest Specification
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Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR.
The Long Term Failure Rates were calculated
at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress
temperature of 150°C to an application temperature of 55°C.
For more information on Reliability Metrics, please click here.
LM20242
