LM2621
Typical Performance Characteristics
Maximum Load Current vs
Input Voltage
(Continued)
10093411
Detailed Description
OPERATING PRINCIPLE
The LM2621 is designed to provide step-up DC-DC voltage
regulation in battery-powered and low-input voltage sys-
tems. It combines a step-up switching regulator, N-channel
power MOSFET, built-in current limit, thermal limit, and volt-
age reference in a single 8-pin MSOP package . The switch-
ing DC-DC regulator boosts an input voltage between 1.2V
and 14V to a regulated output voltage between 1.24V and
14V. The LM2621 starts from a low 1.1V input and remains
operational down to 0.65V.
This device is optimized for use in cellular phones and other
applications requiring a small size, low profile, as well as low
quiescent current for maximum battery life during stand-by
and shutdown. A high-efficiency gated-oscillator topology
offers an output of up to 1A.
Additional features include a built-in peak switch current
limit, and thermal protection circuitry.
10093414
FIGURE 1. Functional Diagram
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