STMicroelectronics L6933H1.2

Overview

L6933H1.2 from STMicroelectronics is a high-performance 2 A ultra-low dropout (ULDO) linear regulator with adjustable output (1.2 V to 5 V), 1 % regulation accuracy, 200 mΩ max r_DS(on), and integrated Power Good output. It features Soft Start, thermal shutdown, short-circuit protection, and supports MLCC output capacitors - used for chipset/RAM supply and mobile PC motherboard power rails.

For engineers reviewing the L6933H1.2 datasheet, L6933H1.2 pinout, L6933H1.2 application, or L6933H1.2 equivalent, key selection criteria include input voltage range (2–14 V), quiescent current (200 µA), load regulation (15 mV), PGOOD threshold (90 % V_OUT), and HSOP8 package compatibility with space-constrained embedded power designs.

Technical Context

The L6933H1.2 employs an internal 50 mΩ N-channel MOSFET as the pass element, enabling low dropout operation down to (V_OUT + 0.2 V) at full 2 A load. Its control loop maintains ±1 % output accuracy over temperature (−25 °C to 125 °C) and line/load variations.

Soft Start is implemented via a precision 5 µA current source charging an external capacitor on the SS/INH pin, generating a controlled V_OUT ramp; the device enters regulation when SS voltage exceeds V_OUT + 1 V. Inhibit functionality is co-located on the same pin with a 0.5 V logic threshold.

Key Specifications

Pinout & Package

Supplied in HSOP8 (Heat Sink Overmolded Plastic) package - thermally enhanced SO-8 variant with exposed thermal pad for improved junction-to-board conduction (R_thJA = 34 °C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ULDO regulator applications.

Compared with TPS7A4701RGWR and ADM7172ACPZ-R7, the L6933H1.2 uniquely combines 2 A output, integrated soft-start/inhibit, and 2 V minimum input in HSOP8 - making it optimal for space-limited, multi-rail embedded systems needing coordinated power-up sequencing.

Availability

L6933H1.2 is available at Aetrix Electronics and suitable for motherboard chipset supply, mobile PC RAM power, and hand-held instrumentation requiring stable component supply with ECOPACK® RoHS-compliant packaging and long-term industrial availability.

Supply support for L6933H1.2 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 headquartered in Geneva, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets with emphasis on power efficiency and reliability.

The L6933H1.2 belongs to ST's high-current linear regulator product line, engineered specifically for point-of-load DC-DC conversion in space-constrained computing and portable electronics where low noise, fast transient response, and thermal robustness are critical.

FAQ

What is the minimum input voltage required for regulation at 2 A output?

The L6933H1.2 maintains regulation with input voltage as low as V_OUT + 0.2 V at full 2 A load due to its 200 mΩ max r_DS(on). For a 1.2 V output, this means VIN ≥ 1.4 V - though the absolute minimum specified operating VIN is 2 V to guarantee all electrical characteristics across temperature and process variation.

Can the PGOOD output drive a microcontroller GPIO directly?

Yes - PGOOD is an open-drain output with 0.2–0.4 V saturation voltage at 1 mA sink current. It can directly interface with 3.3 V or 5 V logic inputs when pulled up to the same rail as the MCU's I/O supply, provided the pull-up resistor is sized to limit current to ≤1 mA during fault condition.

How is thermal performance affected by PCB layout in HSOP8?

Thermal resistance drops significantly when the exposed thermal pad (pin 6 GND) is soldered to ≥2 cm² of inner-layer copper pour with ≥4 thermal vias to ground plane. Without proper pad connection, R_thJA degrades from 34 °C/W to >60 °C/W - potentially triggering thermal shutdown above 1.2 A continuous load.

Is the Soft Start time programmable, and how is it calculated?

Yes - Soft Start time is set by an external capacitor C_SS on the SS/INH pin: T_SS ≈ (V_OUT + 1 V) × C_SS / 5 µA. For example, with V_OUT = 1.2 V and C_SS = 100 nF, T_SS ≈ 2.2 V × 100 nF / 5 µA = 44 ms - verified in typical performance curves Figure 5.