Diodes Incorporated (Nasdaq: DIOD) has launched the AP61406Q, a 5.5V, 4A synchronous buck converter designed for automotive point-of-load (POL) applications, combining compact size, high efficiency, and programmable flexibility via an I2C interface. The device targets infotainment, instrument clusters, telematics, and advanced driver-assistance systems (ADAS).
The AP61406Q features an I2C 3.0-compatible interface supporting SCL clock rates up to 3.4MHz, allowing engineers to program PFM/PWM modes, output currents ranging from 1A to 4A, and switching frequencies of 1MHz to 2.5MHz. It also provides fine 20mV output adjustability and fault status reporting, facilitating system optimization for efficiency and performance.
Encased in a W-QFN1520-8/SWP (Type UX) package, the converter is built for high-power-density automotive POL applications and can withstand elevated ambient temperatures. Its proprietary gate driver minimizes switching node ringing without affecting MOSFET turn-on and turn-off times, reducing high-frequency EMI noise. The device operates across a 2.3V–5.5V input range, integrating a 75mΩ high-side and 33mΩ low-side power MOSFET to ensure efficient step-down DC-DC conversion. Constant on-time (COT) control reduces external components, stabilizes loops, and limits output voltage ripple.
The AP61406Q includes a multi-function enable (EN) input for flexible mode control, supporting ultra-low quiescent current (20µA) in PFM mode and consistent ripple in PWM mode. Its power-good (PG) indicator uses a ±5% window comparator with an internal 5MΩ pull-up resistor, lowering bill-of-materials costs.
Safety and reliability are reinforced through high-side and low-side current sensing for output short circuits, undervoltage lockout (UVLO), input overvoltage protection (OVP), peak and valley current limiting, and thermal shutdown.
Priced at $0.24 per unit in 1,000-piece quantities, the AP61406Q provides automotive-grade performance and flexibility, while the standard AP61406 version offers similar functionality for industrial and consumer markets.
