STMicroelectronics LD59015C33R

Overview

LD59015C33R from STMicroelectronics is a 150 mA low-noise, high-PSRR linear voltage regulator delivering a fixed 3.3 V output with ±1.8% accuracy at 25 °C, 150 mV typical dropout at 150 mA, and 20 µV_RMS output noise (10 Hz–100 kHz). It operates from 2.4 V to 5.5 V input, features logic-controlled shutdown (<1 µA OFF current), and is stable with 1 µF ceramic capacitors. It targets power-sensitive RF and analog circuitry in portable battery-powered systems.

For engineers reviewing the LD59015C33R datasheet, LD59015C33R pinout, LD59015C33R application, or LD59015C33R equivalent, key selection criteria include PSRR performance across 100 Hz–100 kHz, quiescent current behavior under light and full load, thermal shutdown threshold (160 °C), enable logic thresholds (0.4 V low / 0.9 V high), and SOT323-5L package compatibility with space-constrained PCB layouts.

Technical Context

The LD59015C33R employs a bandgap reference-based error amplifier with internal trimming for 3.3 V output regulation, integrated thermal shutdown (160 °C) and short-circuit current limiting (~200 mA), and an enable-controlled pass transistor with 200 µs turn-on time. Its architecture prioritizes low-noise operation via optimized internal biasing and filtering.

PSRR is maintained at 80 dB @ 100 Hz, degrading to 76 dB @ 10 kHz and 54 dB @ 100 kHz due to internal compensation roll-off; line regulation is 0.001 %/V and load regulation is 0.001 %/mA - both measured over full temperature and load range - confirming tight output stability under dynamic supply and load conditions.

Key Specifications

Pinout & Package

Supplied in the compact SOT323-5L surface-mount package (2.0 × 2.1 mm footprint, 0.9 mm height), the LD59015C33R uses a 5-pin configuration with one no-connect terminal to support internal trimming and thermal optimization.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6210B332MR-G and RT9013-33GB, the LD59015C33R provides superior thermal protection, tighter output accuracy, and best-in-class PSRR below 10 kHz - making it optimal for thermally constrained, noise-sensitive applications where reliability is non-negotiable.

Availability

LD59015C33R is available at Aetrix Electronics and suitable for wireless sensor nodes, portable medical devices, wearable audio systems, and industrial IoT edge controllers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LD59015C33R 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, Switzerland, designing and manufacturing microcontrollers, power management ICs, analog chips, and MEMS sensors for automotive, industrial, and consumer markets.

The LD59015 belongs to ST's high-performance LDO family engineered specifically for ultra-low-noise, low-quiescent-current power delivery in battery-operated and signal-integrity-critical applications.

FAQ

What is the minimum input voltage required for regulation at 3.3 V output?

The LD59015C33R requires a minimum input voltage of 3.45 V to maintain regulation at full 150 mA load, based on its 150 mV typical dropout voltage. At lighter loads, regulation is sustained down to 2.4 V input - verified across -40 °C to 125 °C junction temperature.

Can the LD59015C33R be used with 0.47 µF ceramic output capacitors?

No - the datasheet specifies 1 µF minimum ceramic output capacitance (X5R/X7R, ESR < 1 Ω @ 100 kHz) for guaranteed stability. Using 0.47 µF risks oscillation or degraded transient response, as confirmed by Figure 11's ESR vs. COUT stability boundary.

Does the EN pin require a pull-up resistor in normal operation?

No external pull-up is required. The EN pin has internal biasing; applying ≥0.9 V directly (e.g., from MCU GPIO) enables regulation, while ≤0.4 V disables it. Input leakage is ≤100 nA, so standard microcontroller outputs drive it reliably without added components.

How does thermal shutdown behave during continuous overload?

At junction temperatures reaching 160 °C, the LD59015C33R enters thermal shutdown, cutting output current and reducing power dissipation. It remains latched off until temperature falls by ~20 °C (hysteresis), then automatically resumes regulation - a self-protecting cycle validated in Section 4 maximum ratings and Figure 14 ISC vs. VDROP curves.