STMicroelectronics LD2980CM36TR

Overview

LD2980CM36TR from STMicroelectronics is a 3.3 V ultra-low-dropout linear voltage regulator in SOT23-5L package, designed for battery-powered and low-noise systems. It delivers up to 50 mA output current with 7 mV typical dropout at 1 mA load, 80 µA typical quiescent current in active mode, and <1 µA shutdown current. Its logic-controlled INHIBIT pin enables system-level power gating in portable electronics.

For engineers reviewing the LD2980CM36TR datasheet, LD2980CM36TR pinout, LD2980CM36TR application, or LD2980CM36TR equivalent, key selection criteria include dropout voltage at light load, shutdown leakage, output noise (160 µVRMS), thermal shutdown threshold (170 °C), and compatibility with low-ESR ceramic capacitors without external compensation.

Technical Context

The LD2980CM36TR uses a PNP pass transistor architecture enabling ultra-low dropout and minimal quiescent current across temperature. Its internal feedback network includes precision trimmed resistors (R1 = 42.6 kΩ, R2 = 51.15 kΩ) to achieve ±0.5% output voltage tolerance over –40 to 125 °C.

It features TTL-compatible INHIBIT control (logic low ≤0.18 V disables output), no internal pull-up on pin 3, and reverse-current blocking - no body diode conduction from VOUT to VIN. Stability is guaranteed with ≥2.2 µF ceramic output capacitor (ESR < 300 mΩ) for 3.3 V version.

Key Specifications

Pinout & Package

SOT23-5L: 2.95 mm × 1.60 mm × 1.30 mm body, 0.95 mm pitch, exposed pad not electrically connected. RoHS-compliant, ECOPACK2 qualified.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-3302E/TT and TLS850B2TE/V1, the LD2980CM36TR uniquely balances ultra-low dropout (7 mV), sub-µA shutdown, and compact SOT23-5L footprint - making it optimal for miniaturized, battery-critical designs where enable control and noise performance are mandatory.

Availability

LD2980CM36TR is available at Aetrix Electronics and suitable for wearable health monitors, industrial sensor nodes, smart home hubs, and automotive cabin camera modules requiring stable component supply, long-lifecycle support, and consistent parametric performance.

Supply support for LD2980CM36TR 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, sensors, and analog devices for industrial, automotive, and consumer markets.

The LD2980 series belongs to ST's ultra-low-IQ LDO portfolio, engineered specifically for energy-constrained edge devices where micropower operation, small size, and robustness across temperature extremes are non-negotiable.

FAQ

What is the minimum output capacitance required for stability with LD2980CM36TR?

The LD2980CM36TR requires a minimum 2.2 µF X7R or C0G ceramic capacitor on the VOUT pin for guaranteed stability across –40 to 125 °C. This value is specified in ST's Application Notes (Section 7.3) and validated per Figure 18–19 of the datasheet. Using lower capacitance risks oscillation unless a series resistor is added to emulate required ESR.

Can the INHIBIT pin be left unconnected?

No - the INHIBIT pin (pin 3) has no internal pull-up or pull-down. Leaving it floating may cause erratic enable/disable behavior due to noise coupling. If shutdown control is unused, ST mandates connecting INHIBIT directly to VIN to ensure reliable ON-state operation, as stated in Section 7.5 of the datasheet.

Does LD2980CM36TR support reverse current protection?

Yes - the LD2980CM36TR uses a PNP pass transistor without an inherent body diode, preventing reverse current flow from VOUT to VIN. When VOUT exceeds VIN, reverse current is limited to ~160 µA through internal feedback resistors (R1/R2), as characterized in Section 7.6 and Figure 22 of the datasheet.

Is the 3.3 V output version available in tighter initial tolerance?

Yes - the "A" version (e.g., LD2980ABM33TR) provides ±0.5% initial output voltage tolerance at 25 °C, versus ±1% for standard "C" versions. This tighter tolerance is confirmed in Table 5 of the datasheet and supports precision analog rails where post-regulation trimming is impractical.