LM557x and LM2557x SIMPLE SWITCHER Regulators
The new LM557x and LM2557x line of SIMPLE SWITCHER buck regulators feature all of the functions necessary to implement an efficient, high-voltage buck regulator using a minimum of external components.
The new regulators operate with an input voltage range up to 75V and deliver up to 3A of continuous output current. The patented emulated-current-mode architecture provides superior load transient response in low duty cycle applications that are not addressable by traditional current mode control. Operating frequency is adjustable from 50 kHz to 1 MHz, providing industry-leading dynamic range. To reduce EMI, a frequency synchronization pin allows multiple ICs from the family to self-synchronize or to synchronize to an external clock. The new regulators guarantee robustness with cycle-by-cycle current limit, short-circuit protection and thermal shut-down.
LM557x and LM2557x Features:
- Wide input voltage ranges from 6V to 75V
- Adjustable switching frequencies between 50 kHz and 1 MHz
- Adjustable soft-start
- Various output currents
- 0.5A (LM5574 and LM25574)
- 1.5A (LM5575 and LM25575)
- 3.0A (LM5576 and LM25576)
- Emulated current mode architecture
- Excellent transient response
- Ultra-short duty cycle
- Reduced noise sensitivity
SIMPLE SWITCHER Video (6 min):
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