STMicroelectronics’ 40V Industrial & Automotive Linear Regulators: Flexible Efficiency

Apr 17, 2024  Geneva, Switzerland

STMicroelectronics’ LDH40 and LDQ40 voltage regulators for automotive and industrial applications start-up from an input as low as 3.3V, operate with up to 40V applied, and have low quiescent current. The LDH40 delivers up to 200mA and is available in one version only, having adjustable output voltage from 1.2V to 22V. The 250mA LDQ40 is available with a 1.2V-12V adjustable output and a choice of 1.8V, 2.5V, 3.3V, and 5.0V fixed output voltages.

These low-dropout (LDO) regulators ensure efficient power conversion for energy-conscious applications. The quiescent current of 2µA at zero load and 300nA logic-controlled shutdown mode help preserve battery energy in always-on standby systems. The devices are stabilized with a small ceramic capacitor on the output.

The automotive devices are AEC-Q100 qualified and packaged as 2mm x 2mm DFN6L devices with wettable flanks that ease PCB design and facilitate automated optical inspection. Their wide input-voltage range allows connection to a vehicle 12V bus, that can reach up to 40V transient, to power infotainment systems, instrument clusters, and advanced driver-assistance systems (ADAS). With their low quiescent and standby current, they are especially suited to use in electric vehicles.

All the LDOs have system protection and management features including internal current limiting, thermal protection, soft-start, and output active discharge. There is an enable pin for shutdown control and a power-good pin for diagnostic monitoring. The LDQ40 devices also have short-circuit protection.

The LDH40 automotive-grade regulator is in production now in DFN6L wettable flank package. The adjustable-output LDQ40 regulators, in industrial and automotive grade, are in production as well, in the standard DFN6L package and wettable-flank package for automotive applications. The fixed-output LDQ40 automotive parts with 1.8V, 2.5V, 3.3V and 5.0V will be available within Q2. Industrial LDQ40 3.3V and 5.0V will be available by Q3. Pricing for both automotive products starts from $0.47 for 1000 units. The LDQ40 industrial-grade price starts from $0.40 for 1000 units. Free samples for both LDH40 and LDQ40 are available at the ST eStore.

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