Murata Power Solutions | 78SRH-3.3/2-C

The 78SRH-3.3/2-C step-down, switching regulator is a ultra high-efficiency, modern replacements for LM78xx series 1.5 Amp 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 200 KHz switching frequency, combined with a synchronous rectifi er buck regulator topology, provides for effi ciencies exceeding 95%. 78SR switchers can easily drive 2 A loads from 12 V or 24 V supplies—at ambient temperatures up to +70° C—without heat sinks, fans, or thermal derating. A thermally effi cient 3-pin vertical mount SIP occupies less than 0.09in.2 (58 mm2) of pc-board real estate, while a horizontal mount option has an installed height of less than 0.290in. (7.4 mm).

78SR Series 2 A switching regulators are lower cost, improved-effi ciency upgrades for many 78HT2, 78SR1, 78ST1, and PT5100 series switchers. Their higher efficiency ensures signifi cantly lower heat generation and provides increased run time in battery-powered applications, making these regulators ideal for today’s low power “green” applications.

Features:

• Up to 95% effi ciency– no costly heat sinks or fans required
• 3.3 V/2 A & 5 V/2 A models; pin compatible with 1.5 A 78xx regulators
• Wide 8– 32 Vdc input voltage range
• Two package options:
  • 3-pin vertical mount SIP
  • Low profi le, horizontal mount SIP
• No external Input/Output fi lter capacitors required
• –40 to +70° C full load operation at 24 Vin with no derating
• Excellent load (±0.25%) and line (±0.35%) regulation
• Low-cost upgrade for 78HT2, 78SR1, 78ST1, and PT5100 switchers
• Open frame design minimizes self-heating & pc-board footprint
• Includes output short-circuit protection and thermal shutdown
• Low noise output for powering sensitive instrumentation