STMicroelectronics LD57100J110R

Overview

LD57100J110R from STMicroelectronics is a 1.10 V fixed-output, ultra-low-dropout linear regulator (LDO) with NMOS pass transistor architecture, 40 mV typical dropout at 1 A, ±1% output voltage tolerance over −40 °C to +85 °C, and logic-controlled shutdown. It delivers stable post-regulation for low-noise, battery-powered mobile power rails in smartphones and camera modules.

For engineers reviewing the LD57100J110R datasheet, LD57100J110R pinout, LD57100J110R application, or LD57100J110R equivalent, key selection criteria include bias-supply-enabled ultra-low dropout performance, active output discharge, thermal/short-circuit protection, and Flip Chip6 package integration in space-constrained portable designs.

Technical Context

The LD57100J110R uses a dedicated VBIAS pin to drive the gate of an NMOS pass element, enabling operation with VIN as low as VOUT + 40 mV while maintaining regulation-critical for deep-battery-discharge scenarios. Its internal reference (0.500 V ±0.5%) feeds a precision error amplifier that controls the pass device via a high-gain, low-noise feedback loop.

It integrates independent protection blocks: thermal shutdown at 160 °C with 20 °C hysteresis, current limiting (1.5–2.6 A), and an enable-controlled discharge MOSFET (RON = 150 Ω) that actively sinks VOUT to GND during shutdown-reducing residual voltage and preventing cross-conduction in multi-rail systems.

Key Specifications

Pinout & Package

LD57100J110R is housed in a Flip Chip6 package (0.8 mm × 1.2 mm, 0.315 mm height), optimized for minimal PCB footprint and thermal resistance (R_thJA = 60 °C/W on standard 4-layer JEDEC board). The die is mounted face-down with solder bumps directly connecting terminals to PCB pads.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-dropout LDO applications.

Compared with XC6210B112MR-G and RT9080AL-11PU5, LD57100J110R uniquely combines 40 mV dropout, VBIAS-enabled regulation, active discharge, and 0.8×1.2 mm footprint-making it the only option for miniaturized, deep-discharge, multi-rail portable systems demanding precision and speed.

Availability

LD57100J110R is available at Aetrix Electronics and suitable for smartphone power management, camera module biasing, wearable health sensor regulation, and low-power IoT MCU core supply requiring stable component supply across high-mix, low-volume production runs.

Supply support for LD57100J110R 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 power management, microcontrollers, and analog ICs for automotive, industrial, and consumer markets-with broad portfolio certification for AEC-Q100, IEC 61508, and ISO 13849.

LD57100 belongs to ST's high-accuracy, ultra-low-dropout LDO family designed specifically for space- and power-constrained portable electronics-emphasizing minimal footprint, nanoscale quiescent current, and robust protection in battery-fed systems.

FAQ

What is the minimum input voltage required for regulation at 1.10 V output?

The LD57100J110R requires VIN ≥ VOUT + VDROP. With 40 mV typical dropout at 1 A, regulation is guaranteed at VIN ≥ 1.14 V. However, per recommended operating conditions, VIN must be ≥ 0.6 V and ≥ VOUT + VDROP across temperature and load-designers should verify worst-case dropout (80 mV max) yields VIN ≥ 1.18 V for margin.

Can the VBIAS pin be tied directly to VIN?

Yes-if VIN satisfies both conditions: ≥3.0 V and ≥ VOUT + 1.6 V (i.e., ≥2.70 V for 1.10 V output). Since 1.10 V + 1.6 V = 2.70 V, VIN must be ≥3.0 V to meet both. In practice, tying VBIAS to VIN is valid when main supply remains ≥3.0 V throughout operation-otherwise, a dedicated 3.3 V bias rail is required.

Does the SNS pin require a separate PCB trace in fixed-output configuration?

Yes. Per datasheet Figure 4 and Table 1, SNS is the output voltage sense node in fixed versions and must connect to the load via a dedicated, low-impedance PCB trace-separate from the main VOUT power path-to enable Kelvin sensing and compensate for IR drop in high-current paths.

How does the output discharge function behave during shutdown?

When EN is pulled low, the internal 150 Ω discharge MOSFET connects VOUT to GND, discharging the output capacitor rapidly. Typical discharge time depends on COUT value-for example, with 10 µF, VOUT falls from 1.10 V to <100 mV in <1 ms. This prevents back-powering of upstream circuitry and ensures safe power sequencing.