STMicroelectronics LD1086D2T12TR

Overview

LD1086D2T12TR from STMicroelectronics is a fixed-output 1.2 V, 1.5 A low-dropout linear voltage regulator in D²PAK package, featuring ±1% output tolerance at 25 °C, 1.3 V typical dropout at full load, internal thermal and current limiting, and operation from –40 °C to +125 °C. It serves as a primary post-regulation stage in industrial power supplies and embedded control modules requiring stable low-voltage bias for microcontrollers and analog circuitry.

For engineers reviewing the LD1086D2T12TR datasheet, LD1086D2T12TR pinout, LD1086D2T12TR application, or LD1086D2T12TR equivalent, key selection considerations include dropout voltage at 1.5 A, output tolerance over temperature, quiescent current behavior under varying load, and compatibility with minimal 10 µF output capacitance for stability.

Technical Context

The LD1086D2T12TR implements a PNP-based LDO architecture with on-chip trimming for tight output voltage accuracy. Its reference voltage is internally set to 1.25 V, enabling fixed 1.2 V output via precision resistor ratio feedback integrated into the die - eliminating external adjust components while retaining thermal regulation and short-circuit foldback.

Unlike traditional PNP regulators, its quiescent current flows entirely into the load rather than being wasted as base current, improving efficiency at light loads. Dropout voltage remains stable across –40 °C to +125 °C, with guaranteed ≤1.5 V at 1.5 A and <1.3 V typical, supporting input-to-output differentials as low as 2.2 V for reliable 1.2 V rail generation.

Key Specifications

Pinout & Package

LD1086D2T12TR uses the D²PAK (SMD 3L STD-ST) package with exposed thermal pad connected to OUTPUT. The package provides low R_thJC = 3 °C/W for efficient heat transfer to PCB copper.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-output LDO applications.

Compared with TLV1117-12CDR and NCP1117DT12RKG, the LD1086D2T12TR delivers 50% higher current, superior thermal performance via D²PAK thermal pad, and tighter output tolerance - making it the sole choice for thermally demanding 1.2 V/1.5 A applications where reliability and headroom are critical.

Availability

LD1086D2T12TR is available at Aetrix Electronics and suitable for industrial motor control, automotive body electronics, programmable logic modules, and medical sensor hubs requiring stable component supply with long-term manufacturability.

Supply support for LD1086D2T12TR 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 automotive-grade analog ICs, with manufacturing ISO/TS 16949-certified facilities.

The LD1086 series targets high-reliability industrial and automotive power regulation, designed specifically to replace aging 3-terminal adjustable regulators with improved dropout, accuracy, and thermal robustness in space-constrained designs.

FAQ

What is the minimum input voltage required for LD1086D2T12TR to regulate 1.2 V at 1.5 A?

The minimum input voltage is 2.5 V, calculated as V_OUT + V_DROP(max) = 1.2 V + 1.5 V. At 1.5 A and 25 °C, typical dropout is 1.3 V, so 2.5 V ensures margin. Operation below 2.5 V results in pass transistor saturation and unregulated output.

Can LD1086D2T12TR be used without an output capacitor?

No. A minimum 10 µF output capacitor is mandatory for stability per datasheet Figure 20 and Section 4. Omitting it causes oscillation at ~100 kHz, leading to excessive output ripple (>100 mVpp) and potential downstream logic errors or ADC inaccuracies.

Is the D²PAK thermal pad electrically isolated?

No. The exposed thermal pad is internally connected to the OUTPUT pin, as confirmed in Figure 2 (pin connections) and Section 2 note: "The TAB is physically connected to the output." PCB land pattern must tie the pad directly to the 1.2 V output plane, not to GND or a separate thermal slug.

Does LD1086D2T12TR support reverse polarity protection?

No. The device lacks internal reverse-battery protection. Applying reversed input voltage forward-biases the substrate diode between IN and GND, causing immediate latch-up and permanent damage. An external series Schottky diode or ideal diode controller is required for reverse-polarity resilience.