Murata Power Solutions’s 78SR-3.3/2 (3.3V, 2 Amp output) and 78SR-5/2 (5V, 2 Amp output) step-down, switching regulators are ultra high-efficiency, modern replacements for LM78xx series 1.5Amp linear regulators. They are pin- and size-compatible, drop-in replacements for TO-220 style, 3-pin SIP or modular packages which require heat sinks. And, to ensure the lowest installed cost, no messy thermal grease, no mounting hardware and no external components are required for full operation.
A 200KHz switching frequency, combined with a synchronous rectifier buck regulator topology, provides for efficiencies exceeding 95%. 78SR switchers can easily drive 2A loads from 12V or 24Vsupplies—at ambient temperatures up to +70°C—without heat sinks, fans, or thermal derating. A thermally efficient 3-pin vertical mount SIP occupies less than 0.09in.2 (58mm2) of pc-board real estate, while a horizontal mount option has an installed height of less than 0.290in. (7.4mm).
78SR Series 2A switching regulators are lower cost, improved-efficiency upgrades for many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher efficiency ensures significantly lower heat generation and provides increased run time in battery-powered applications, making these regulators ideal for today’s low power “green” applications.