STMicroelectronics BAT46

Overview

BAT46 from STMicroelectronics is a general-purpose silicon Schottky diode optimized for low-voltage, high-speed switching applications, featuring 100 V repetitive peak reverse voltage, 150 mA forward continuous current at 25°C, 0.45 V forward voltage at 10 mA, 10 pF junction capacitance at 0 V, and DO-35 glass package with axial leads. It serves as a signal-level rectifier or clamping diode in power supply front-ends and signal conditioning circuits.

For engineers reviewing the BAT46 datasheet, BAT46 pinout, BAT46 application, or BAT46 equivalent, key selection criteria include its low forward voltage drop for efficiency-critical 3.3 V/5 V rail clamping, temperature-stable leakage performance up to 125°C, and DO-35 mechanical compatibility with through-hole prototyping and legacy board layouts.

Technical Context

The BAT46 employs a metal-to-silicon Schottky barrier structure enabling fast recovery (no minority carrier storage) and low forward conduction loss. Its 100 V V_RRM rating supports use in 48 V automotive and industrial auxiliary supplies, while its 300 °C/W junction-to-ambient thermal resistance reflects standard DO-35 lead-frame conduction cooling without heatsinking.

Leakage current remains below 5 µA at 75 V and 60°C (typical), and junction capacitance drops from 10 pF at 0 V to 6 pF at 1 V reverse bias-enabling stable RF detector and high-frequency clamp behavior up to ~100 MHz.

Key Specifications

Pinout & Package

DO-35 glass axial-leaded package with cathode identified by a ring marking; leads are tinned copper-clad steel, 0.458–0.558 mm diameter, 3.05–4.50 mm body length.

Key Features

Applications

Availability

BAT46 is available at Aetrix Electronics and suitable for power supply clamping, RF detection, logic-level shifting, and reverse polarity protection requiring stable component supply across industrial control, sensor node, and legacy embedded designs.

Supply support for BAT46 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, MCU, power, and sensing solutions for industrial, automotive, and consumer markets.

The BAT46 belongs to ST's general-purpose discrete diode product line, engineered for cost-sensitive, high-reliability signal integrity and protection functions in space-constrained through-hole applications.

FAQ

Is BAT46 suitable for 24 V automotive applications?

Yes. With 100 V V_RRM and guaranteed operation up to 125°C junction temperature, BAT46 withstands load-dump transients and ambient heat in 24 V vehicle subsystems. Its leakage stays below 20 µA at 75 V and 60°C, ensuring reliable clamping without excessive quiescent drain.

How does BAT46 compare to 1N5711 in high-frequency use?

BAT46 offers lower typical junction capacitance (10 pF vs. 1N5711's 12 pF at 0 V) and tighter V_F distribution (0.25–0.45 V vs. 0.3–0.5 V), yielding more predictable detector output and reduced harmonic distortion above 50 MHz. Both share DO-35 packaging and similar thermal limits.

Can BAT46 replace BAT54 in surface-mount designs?

No. BAT46 uses DO-35 axial leads and is not a drop-in replacement for SOT-23-packaged BAT54. While both are Schottky diodes, their packages, thermal paths, and layout footprints are incompatible. For SMT equivalents, consider ST's BAT54 series or SMBJ variants with matching V_RRM and I_F.

What is the maximum soldering temperature for BAT46?

The BAT46 DO-35 package supports a maximum soldering temperature of 230°C for 10 seconds at 4 mm from the case, per STMicroelectronics' mechanical data. Exceeding this risks glass-to-metal seal degradation and increased leakage or open-circuit failure.