peculiarity
V OUT = 0.8V/1.2V
V IN = 2.5V to 5.5V
1.5A maximum load capacity
The 3.3MHz PWM fixed switching frequency (typical) allows the use of a 1μH inductor
+/- 3% DC output voltage accuracy
0.01μA typical shutdown current
High efficiency internal synchronous rectification
Internal soft start
Current overload and thermal shutdown protection
illustrate
The LM3678 step-down DC-DC converter is optimized to power a 2.5V to 5.5V low-voltage circuit from a single-cell Li-Ion battery and input rail. It can deliver up to 1.5A of load current over the entire input voltage range. The LM3678 is available in 0.8V/1.2V options. One is that the voltage is set via the VSELECT pin.
The LM3678 uses a 3.3MHz fixed-frequency PWM mode. Internal synchronous rectification provides high efficiency during PWM mode operation. In shutdown mode, the device shuts down, reducing battery consumption by 0.01μA (typical).
The LM3678 is available in a 3mm x 3mm LLP-10 package. A high switching frequency of 3.3MHz (typical) allows the use of tiny surface mount components. There are only three external surface mount components, an inductor and two ceramic capacitors, (solution size less than 33 mm2). For other voltage ratio rated voltage ranges, please refer to the Ordering Information section or Contact National Semiconductor.
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