STMicroelectronics L9001

Overview

L9001 from STMicroelectronics is an AEC-Q100 qualified automotive power supply IC integrating three configurable voltage regulators (VDD1 buck, VDD2 buck/LDO, ADCLDO), supervision circuitry (VS monitoring, overtemperature detection, output overcurrent protection), and fail-safe functions including watchdog, reset generation, and low-power mode. It delivers 3.3/5.0/6.0 V @ 1 A (VDD1), 0.8–5.0 V @ 1 A (BUCK) or 300 mA (LDO) (VDD2), and 3.3/5.0 V @ 100 mA (ADCLDO) for microcontroller core, peripherals, and ADC supplies in engine control units and body electronics.

For engineers reviewing the L9001 datasheet, L9001 pinout, L9001 application, or L9001 equivalent, key selection considerations include regulator configuration flexibility via CONF pins, integrated diagnosis (VR1/FB2/ADCMON reset outputs), thermal warning (TWN), watchdog timing (WDT/WDO), and PowerSSO-24 package thermal performance with exposed pad.

Technical Context

The L9001 implements a hierarchical power architecture: VDD1 operates as a primary asynchronous buck regulator sourcing VS (5.5–18 V) to generate up to 6 V/1 A; its output can feed VDD2 or external loads. VDD2 is reconfigurable via CONF2 as either a synchronous buck (0.8–5.0 V/1 A) or linear regulator (300 mA), with feedback via FB2 and reset assertion on fault.

Supervision is hardware-dedicated: VS undervoltage/overvoltage triggers safe-state shutdown; internal temperature sensing asserts TWN at warning threshold and forces safe state at shutdown threshold; charge pump (CP/CP1/CP2) integrity is continuously monitored. The watchdog block uses WDT capacitor timing and WDI signal synchronization to assert WDO on timeout.

Key Specifications

Pinout & Package

Package: PowerSSO-24 with exposed thermal pad (down-facing), optimized for high-power dissipation in automotive under-hood environments. Thermal resistance junction-to-case is 2 °C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multi-rail automotive power management applications.

Compared with MAX20090 and TPS65381A-Q1, the L9001 uniquely combines VDD2's BUCK/LDO configurability, integrated ADCLDO, and hardware-monitored charge pump-making it optimal for mixed-signal automotive nodes requiring both precision analog and robust digital power with minimal external components.

Availability

L9001 is available at Aetrix Electronics and suitable for engine control units, ADAS domain controllers, body control modules, and electric power steering systems requiring stable component supply across automotive production lifecycles.

Supply support for L9001 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader specializing in automotive, industrial, and power management solutions, with broad portfolio coverage from discrete devices to complex SoCs.

The L9001 belongs to ST's SPS (Simple Power Supply) family, designed specifically for single-chip integration of multiple regulated rails, supervision, and fail-safe logic in space-constrained automotive ECUs.

FAQ

What configuration pins control VDD2 output voltage and mode?

VDD2 output voltage is set by an external resistor divider on FB2, while its operating mode (BUCK or LDO) is selected solely by the logic level on CONF2: HIGH configures BUCK mode (0.8–5.0 V/1 A), LOW configures LDO mode (300 mA). No firmware or register writes are involved-configuration is hardware-determined at power-up.

How does the L9001 enter and exit SAFE mode?

SAFE mode activates automatically upon detection of VS undervoltage/overvoltage, junction temperature exceeding shutdown threshold, or charge pump failure. All regulator outputs disable, RSTN1/RSTN2/ADCMON assert low, and TWN goes active. Exit requires VS return to valid range, temperature drop below threshold, and successful charge pump restart-followed by a full power-up sequence.

Can VDD1 and VDD2 operate simultaneously from the battery (VS)?

No. When VDD2 is supplied directly from VS (not from VR1), the L9001 automatically disables VDD1 to prevent conflict. This interlock ensures only one primary regulator draws from battery at a time-either VDD1 feeding VDD2, or VDD2 operating standalone from VS. The configuration is enforced internally without external logic.

What is the function of the CP, CP1, and CP2 pins?

CP is the charge pump output driving high-side gate drivers; CP1 and CP2 connect to external capacitors forming the charge pump network. These pins are continuously monitored-undervoltage on CP triggers SAFE mode. The charge pump enables efficient high-side switching in VDD1/VDD2 buck stages and must be properly decoupled per Table 18 in the datasheet to ensure stable regulation.