STMicroelectronics LDBL20D-25R

Overview

LDBL20D-25R from STMicroelectronics is a 2.5 V fixed-output, 200 mA ultra-low-dropout linear regulator with 200 mV typical dropout at full load, 20 µA typical quiescent current at no-load, ±1.5% output voltage accuracy at 25 °C, and operation from 1.5 V to 5.5 V input. It integrates logic-controlled shutdown, internal soft-start, and optional output discharge, and is stabilized with ≥0.47 µF ceramic output capacitance.

For engineers reviewing the LDBL20D-25R datasheet, LDBL20D-25R pinout, LDBL20D-25R application, or LDBL20D-25R equivalent, this device is selected for space-constrained, battery-powered systems requiring precise low-noise biasing of RF transceivers, camera sensors, and wearable MCU cores where standby current <0.2 µA and thermal robustness to 125 °C are critical.

Technical Context

The LDBL20D-25R employs a bandgap-referenced op-amp control loop with internal bias generator and thermal protection circuitry. Its dropout behavior is defined by a PMOS pass transistor with 200 mV typical V_DS at 200 mA, enabling regulation down to V_IN = V_OUT + 0.2 V.

Enable logic operates with V_EN(H) ≥ 1 V and V_EN(L) ≤ 0.4 V across -40 °C to 125 °C; internal soft-start limits turn-on time to 100 µs, while optional discharge MOSFET (RON = 100 Ω) actively pulls VOUT to GND during shutdown.

Key Specifications

Pinout & Package

Package: STSTAMP™ (0.47 × 0.47) mm², 4-pin wafer-level chip-scale package (WLCSP) with bottom-side solder balls; footprint matches JEDEC MO-220WEED, compatible with standard SMT reflow.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6210B252MR-G, LDBL20D-25R adds essential system-level controls (EN, thermal shutdown) and lower IQ for battery longevity; versus RT9013-25GB, it trades current capacity for 3× lower IQ and 40× smaller footprint-critical for miniaturized portable electronics.

Availability

LDBL20D-25R is available at Aetrix Electronics and suitable for mobile phone power management, wearable biosensor biasing, digital still camera sensor regulation, and portable media player audio subsystems requiring stable component supply, long-lifecycle support, and wafer-level packaging for high-density layouts.

Supply support for LDBL20D-25R 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 silicon solutions for automotive, industrial, and consumer markets since 1987.

LDBL20D-25R belongs to the LDBL20 ultra-low-IQ LDO family, engineered specifically for space- and energy-constrained portable electronics where sub-µA shutdown, minimal footprint, and ceramic-capacitor compatibility are mandatory design requirements.

FAQ

What is the minimum input voltage required for LDBL20D-25R to regulate 2.5 V output?

The minimum input voltage is 2.7 V under full 200 mA load, based on the 200 mV typical dropout voltage specification. At lighter loads, regulation is maintained down to 1.5 V input, but output voltage accuracy degrades outside the recommended VIN ≥ VOUT + 0.3 V range per datasheet Section 5.

Does LDBL20D-25R require an external capacitor on the EN pin for noise immunity?

No external capacitor is required on the EN pin. The enable input has 100 nA typical leakage current and specified VIH/VIL thresholds (≥1 V / ≤0.4 V) that ensure reliable logic-level interfacing with standard GPIOs; layout best practice is to route EN away from noisy switching nodes rather than add filtering.

Can LDBL20D-25R be used with a 0.22 µF output capacitor?

A 0.22 µF ceramic capacitor falls below the 0.47 µF minimum recommended value and risks instability under certain load/temperature conditions, as shown in Figure 17 (stability area vs COUT/ESR). While marginal operation may occur at room temperature and light loads, ST specifies 0.47 µF as the minimum for guaranteed stability across -40 °C to 125 °C.

Is the output discharge feature enabled by default on LDBL20D-25R?

Yes-the "D" suffix in LDBL20D-25R indicates inclusion of the optional output discharge MOSFET (RON = 100 Ω), which actively discharges the output capacitor when EN is pulled low. This feature is factory-configured and cannot be disabled; alternative part numbers (e.g., LDBL20-25R) omit this function.