Configurable Automotive Low-Dropout Regulators from STMicroelectronics Provide Diagnostics for Functional Safety

STMicroelectronic L99VR01

With eight selectable fixed-output voltages, diagnostic features for functional safety, and high thermal performance, STMicroelectronics’ L99VR01 AEC-Q100 qualified low-dropout linear voltage regulators simplify system design and ease inventory management for multiple automotive applications.

STMicroelectronic - L99VR01

The regulators supply up to 200 mA for powering loads such as body modules, junction boxes, instrument clusters, sunroof controllers, keyless-entry controllers, and sensors. The output voltage can be set to 0.8 V, 1.2 V, 1.5 V, 1.8 V, 2.5 V, 2.8 V, 3.3 V, or 5 V more accurately than with an external voltage divider using three external selection pins. The output is within ±2% of the nominal value.

Two device versions are available. The L99VR01S comes in a standard SO-8 package with Enable and Reset pins as well as safety features such as fast output discharge, under-voltage lockout (UVLO), thermal shutdown, and short-circuit protection. The quiescent current is reduced to 1 μA when disabled and the regulator operates from –40 °C to 150 °C.

The L99VR01J in PowerSSO-12 additionally allows programming the short-circuit current limit, provides thermal warning and output-overvoltage status indications, and contains a programmable watchdog that checks for correct operation of the host microcontroller. The L99VR01J also has a wider operating junction temperature range, from –40 °C to 175 °C.

By integrating output overvoltage monitoring, the new regulators can provide constant load protection. The diagnostic features ease the design of functional-safety related applications, helping users achieve the required ISO 26262 ASIL value. Appropriate supporting documentation is available on request.

Both variants feature a wide input-voltage range, from 2.15 V to 28 V, allowing use in applications connected directly to the battery voltage, VBAT, or for post-regulation to convert an already regulated voltage. The inputs are 40 V tolerant to withstand load dump.

Both variants are in production now. Pricing for orders of 1000 pieces starts from $0.28 for the L99VR01S and from $0.35 for the L99VR01J.