LM2840XMK-ADJL/NOPB

The LM284x SIMPLE SWITCHER devices are PWM DC/DC step-down voltage regulators. These devices feature an input range of 4.5V to 42V, making them suitable for a variety of applications (e.g., power regulation from unregulated sources). They have a low RDSON (typically 0.9Ω) internal switch, enabling maximum efficiency (typically 85%). Additionally, they offer fixed operating frequencies of 550kHz (X option) and 1.25MHz (Y option), supporting small external components while ensuring low output voltage ripple. Soft-start can be implemented by combining the shutdown (SHDN) pin with an external RC circuit, allowing users to adjust the soft-start time according to specific applications. After optimization, the LM2840 can handle a load current of up to 100mA, the LM2841 up to 300mA, and the LM2842 up to 600mA. They all have a nominal feedback voltage of 0.765V. Other features of these devices include thermal shutdown, VIN under-voltage lockout, and gate driver under-voltage lockout. All LM284x devices come in a low-profile SOT-6L package.

Applications

• Battery-powered devices
• Industrial distributed power applications
• Portable media players
• Portable handheld instruments

Key features

• 4.5V to 42V input voltage
• 100mA, 300mA, and 600mA output current options
• 0.765V feedback pin voltage
• 550kHz (X) or 1.25MHz (Y) switching frequency
• Low shutdown I0: 16μA typical
• Short-circuit protection
• Internal compensation
• Soft-start circuit
• Compact overall solution size (SOT-6L package)
• Custom design using LM2840 (or LM2841/42) with WEBENCH Power Designer