5.5V, 4A, Low IQ Synchronous Buck Converter with Versatile I²C Interface from Diodes Incorporated is Optimized for Efficiency and Size in Automotive POL Systems

Key Terms

synchronous buck converter technical

A synchronous buck converter is an electronic device that efficiently reduces a higher voltage to a lower one, much like a water valve controlling the flow from a larger pipe to a smaller one. It uses special components to switch energy on and off rapidly, ensuring less energy is wasted as heat. This technology is important in managing power supplies for electronic devices, helping them run reliably and efficiently.

i2c 3.0-compatible technical

i2c 3.0-compatible means a device can speak the i²c (Inter-Integrated Circuit) communication standard at its 3.0 specification, the common “language” that lets small chips and sensors exchange data on a circuit board. For investors, compatibility signals easier integration with other components, lower engineering costs, and broader market acceptance, which can speed product development and increase potential sales in electronics markets.

pwm technical

Private wealth management is a personalized financial service for high-net-worth individuals that combines investment advice, tax planning, estate guidance and other money-management tasks under one roof. Think of it as a tailored financial playbook and coach that helps preserve and grow a person’s assets while addressing risks and goals; investors monitor changes in a firm’s wealth-management business because it can signal revenue stability, fee income and client trust.

mosfet technical

A MOSFET is a tiny electronic switch used to control the flow of electricity in chips and circuits, functioning like a faucet that turns current on or off and adjusts how much passes through. Investors watch MOSFETs because their performance, cost and availability affect product power efficiency, manufacturing yields and supply chains for industries from consumer electronics to electric vehicles, which in turn can influence companies’ margins and growth prospects.

constant on-time (cot) control technical

Constant on-time (COT) control is a method used to ensure that payments or cash flows happen exactly when scheduled, without delay. For investors, it provides confidence that financial obligations will be met promptly, reducing uncertainty and helping to manage risk. Think of it like a train arriving precisely on schedule, ensuring smooth and reliable operations.

undervoltage lockout (uvlo) technical

Undervoltage lockout (UVLO) is a safety feature in electronic devices that prevents a system from turning on or operating if the power supply voltage drops below a certain level. Think of it as a safety switch that ensures the device only runs when it has enough power to function properly, helping to protect both the device and connected components. For investors, UVLO indicates a focus on device reliability and power management, which can impact overall product quality and performance.

thermal shutdown technical

Thermal shutdown is a built-in safety feature in electronic devices or equipment that automatically turns off or limits operation when internal temperature gets too high, like a stove’s thermostat tripping to prevent burning. For investors, it matters because frequent or improper thermal shutdowns can signal design flaws, lead to product downtime, higher repair or warranty costs, recalls, regulatory scrutiny, or reputational damage — all of which can affect revenue and valuation.

PLANO, Texas--(BUSINESS WIRE)-- Diodes Incorporated (Diodes) (Nasdaq: DIOD) today introduces the AP61406Q, a new 5.5V, 4A member with I²C interface of its low quiescent current (I_Q), automotive-compliant* synchronous buck converters. The I²C interface allows the programming of various parameters enabling it to meet the growing demand for compact design and high efficiency in various automotive point-of-load (POL) applications, including infotainment, instrument clusters, telematics, and advanced driver assistance systems (ADAS).

A key advantage of the AP61406Q is its I²C 3.0-compatible serial interface, which supports SCL clock rates up to 3.4MHz. This interface enables programmability for various parameters, including PFM/PWM modes, frequencies (1MHz, 1.5MHz, 2MHz, 2.5MHz), and output currents (1A/2A/3A/4A). The device also provides 20mV increment V_OUT adjustability and provides fault status reports.

Optimized for high power density automotive POL applications, the AP61406Q is available in a W-QFN1520-8/SWP (Type UX) package, enabling it to operate at high ambient temperatures. The device also features a proprietary gate driver scheme that effectively resists switching node ringing without compromising MOSFET turn-on and turn-off times, thereby reducing high frequency radiated EMI noise.

The AP61406Q operates with an input voltage range of 2.3V to 5.5V. It integrates a 75mΩ high-side and a 33mΩ low-side power MOSFET to provide high-efficiency step-down DC-DC conversion. Its adoption of constant on-time (COT) control minimizes external component count, facilitates loop stabilization, and results in low output voltage ripple.

The multi-function enable (EN) input also provides control of the mode of operation. This capability enables flexibility for low I_Q (20µA), high-load efficiency in fixed PFM mode or equal ripple across load conditions in PWM mode. Additional features include an accurate power good (PG) indicator with an internal 5MΩ pull-up resistor with a ±5% window comparator circuit, which reduces bill-of-materials (BOM) costs.

The AP61406Q has high-side and low-side current sense protection during output short circuits, increasing its reliability in automotive POL applications. Other protection features include undervoltage lockout (UVLO), V_IN overvoltage protection (OVP), peak and valley current limiting, and thermal shutdown.

The AP61406Q is available at $0.24 in 1,000-piece quantities. A standard compliance version, AP61406, is available and suitable for industrial and consumer applications.

For further information, please visit: https://www.diodes.com/products/power-management/dc-dc-converters/integrated-power-stage/buck-converter/

About Diodes Incorporated

Diodes Incorporated (Nasdaq: DIOD), a Standard and Poor’s SmallCap 600 and Russell 3000 Index company, delivers high-quality semiconductor products to the world’s leading companies in the automotive, industrial, computing, consumer electronics, and communications markets. We leverage our expanded product portfolio of analog and discrete power solutions combined with leading-edge packaging technology to meet customers’ needs. Our broad range of application-specific products and solutions-focused sales, coupled with global operations including engineering, testing, manufacturing, and customer service, enable us to be a premier provider for high-volume, high-growth markets. For more information, visit www.diodes.com.

*Automotive-compliant - AEC qualified, manufactured in facilities certified to IATF 16949, supporting PPAP documents.

The Diodes logo is a registered trademark of Diodes Incorporated in the United States and other countries.

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Gurmeet Dhaliwal

Vice President, Corporate Marketing & Investor Relations

Diodes Incorporated

+1 408-232-9003

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Source: Diodes Incorporated (P)