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
7A shutdown current
Patented current sensing for current mode control
Input undervoltage lockout
Adjustable soft-start
Current limit and thermal shutdown
16-pin TSSOP package
Application Personal digital assistants (PDAs)
Computer peripherals
Battery-powered devices
Handheld scanners
High efficiency 5V conversion
Pinout
SpecificationsIf Military/Aerospace specified devices are required,please contact the National Semiconductor Sales Office/Distributors for availability and specifications.
| Input Voltage |
15V |
| Feedback Pin Voltage |
−0.4V £ VFB £ 5V |
Power Dissipation (TA =25°C),
(Note 2) |
893 mW |
| Junction Temperature Range |
−40°C £ TJ £ +125°C |
| Storage Temperature Range |
−65°C to +150°C |
ESD Susceptibility
Human Body Model (Note 3) |
1kV |
DescriptionThe 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 10A.
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.
LM2651 Data Sheet
