STMicroelectronics STPS140Z

Overview

STPS140Z from STMicroelectronics is a single Schottky rectifier optimized for low-voltage, high-frequency DC-DC converters and switch-mode power supplies, featuring 1 A continuous forward current (IF), 40 V repetitive peak reverse voltage (VRRM), and a maximum forward voltage drop of 0.49 V at rated current and 150°C junction temperature - deployed in GSM power rails and PCMCIA polarity protection circuits.

For engineers reviewing the STPS140Z datasheet, STPS140Z pinout, STPS140Z application, or STPS140Z equivalent, this device is selected for ultra-low conduction loss, negligible switching loss, and SOD-123 footprint compatibility with space-constrained portable electronics designs requiring fast recovery and thermal stability up to 150°C.

Technical Context

This Schottky diode uses a metal–semiconductor junction to eliminate minority-carrier storage delay, enabling near-zero reverse recovery time and supporting operation above 1 MHz in synchronous rectification and freewheeling paths. Its low VF (0.45–0.51 V typ. at 100°C/1 A) directly reduces conduction loss in battery-powered DC-DC stages.

The SOD-123 package delivers Rth(j-a) = 175 °C/W on 50 mm² copper (35 µm), and dV/dt rating of 10,000 V/µs ensures robustness against rapid voltage transients in inductive switching nodes without snubbers.

Key Specifications

Pinout & Package

SOD-123 surface-mount package: 2-terminal, cathode-banded, plastic-encapsulated diode with 3.55–3.95 mm length, 2.55–2.85 mm width, and 1.45 mm height; designed for reflow soldering (TL = 260°C for 10 s).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Schottky rectifier applications.

Compared with NSS1C200MT1G, STPS140Z provides 2× reverse voltage headroom for industrial 24 V inputs; versus VS-1EQH04HM3/85A, it saves 40% board area and improves thermal resistance on minimal copper, making it optimal for space- and thermally constrained portable designs.

Availability

STPS140Z is available at Aetrix Electronics and suitable for portable DC-DC converters, GSM power management modules, and high-frequency freewheeling applications requiring stable component supply across production lifecycles.

Supply support for STPS140Z 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, designing and manufacturing analog, power, microcontroller, and sensor solutions for automotive, industrial, and consumer markets.

The STPS series targets high-efficiency, low-voltage power conversion - specifically engineered for Schottky rectification in space-sensitive, thermally demanding portable and telecom power architectures.

FAQ

What is the maximum junction temperature for continuous operation?

The STPS140Z has a maximum operating junction temperature (Tj) of 150°C, validated under steady-state conditions with IF = 1 A at Tamb = 60°C and 50 mm² copper cooling area. Derating is required above Tamb = 60°C per Fig. 2 in the datasheet, where average forward current drops to ~0.6 A at 100°C ambient.

Can STPS140Z replace a standard PN rectifier in an existing 5 V buck converter?

Yes - its 0.49 V VF at 1 A reduces conduction loss by ~55% versus a typical 1N5819 (VF ≈ 0.45–0.55 V but with higher Tj sensitivity and Qrr). However, verify reverse leakage at elevated temperature, as IR reaches 5 mA at Tj = 100°C and VR = 40 V, which may affect light-load efficiency.

Is the SOD-123 package compatible with standard reflow profiles?

Yes - the STPS140Z is qualified for lead-free reflow soldering with a maximum peak temperature of 260°C for 10 seconds (per JEDEC J-STD-020). Its epoxy meets UL94 V0 flammability rating, and the cathode band enables automated optical alignment during pick-and-place.

Does STPS140Z require a heatsink in 1 A operation?

No - with Rth(j-a) = 175 °C/W on 50 mm² copper (35 µm), power dissipation of ~0.49 W at 1 A yields ~86°C junction rise above ambient. At Tamb = 60°C, Tj ≈ 146°C - within spec. A heatsink is unnecessary unless ambient exceeds 70°C or copper area is reduced below 30 mm².