BAT54A-QR

BAT54A-QR is a dual Schottky diode pair in one SOT-23 package with a common terminal (the BAT54A variant has a common terminal; other BAT54 variants exist with different common connections). The “-QR” suffix indicates Tape‑and‑Reel (Q) packaging for automated assembly (RoHS-compliant reel packaging).
Key points
- Configuration: two Schottky diodes sharing a common node (commonly used as a diode-OR or for polarity protection).
- Ratings: typically around 20 V reverse voltage and about 200 mA per diode.
- Forward drop: very low, ~0.2–0.3 V at modest current; fast switching with negligible reverse recovery.
- Leakage: low at room temperature, increases with temperature.
- Package: compact 3-pin SOT-23, suitable for surface-mount boards.
Common uses
- Diode-ORing of supply rails, level shifting, and simple reverse-polarity protection.
- fast switching circuits, clamping, and protection in low-voltage logic and power paths.
Note
- Verify the exact pinout (common terminal location) in the specific datasheet for your lot, as packaging variants exist.

Equivalent parts to BAT54A-QR (dual Schottky diodes with a common anode in SOT-23) include:
- BAS54A (Vishay/Diodes Inc) – dual Schottky, common anode, SOT-23
- Other vendors’ BAT54A cross-references (e.g., ON Semiconductor, Nexperia) in the same topology
- Any dual Schottky with common anode and similar ratings (≈30 V, 0.2–0.5 A) in SOT-23; use cross-ref tables to match.

Here are the key features of BAT54A-QR:
- Dual Schottky diodes in one SOT-23 package with common anode (BAT54A configuration)
- VRRM (repetitive reverse voltage): 30 V
- IF(AV) (continuous forward current): typically 200 mA
- Very low forward voltage drop (Schottky): ~0.25–0.40 V at modest currents (fast switching, no stored charge)
- Fast switching characteristics (Schottky diodes, no minority-carrier storage)
- Low leakage current at room temperature (microamps; increases with temperature)
- Low junction capacitance (suitable for high-speed, RF, and rectification tasks)
- RoHS compliant and Pb-free
- Packaging: Tape-and-reel (QR) for automated assembly
Note: Exact voltage, current, and leakage figures can vary by lot and temperature; consult the latest datasheet for precise values.

- Pin count: 3 pins (dual diodes with a common anode).
- Function: BAT54A-QR is a dual Schottky diode array with a common anode. The two diodes share the same anode and have individual cathodes, used for low-forward-voltage drop applications such as OR-ing, level shifting, and input/reverse-polarity protection in high-speed circuits.

Manufacturer: Vishay Intertechnology, Inc. (Vishay).
What kind of company: A global American multinational manufacturer of electronic components, including discrete semiconductors (diodes, transistors) and passive components (resistors, capacitors, inductors).

BAT54A-QR is a dual Schottky diode in a small SMD package with common anode. Its very low forward voltage and fast switching suit:
- Diode-OR gates and logic-level shifting in low-power digital circuits
- Input protection/clamping for microcontrollers and analog interfaces (limits to Vcc/GND)
- Simple rectification, envelope detection, and detector circuits in RF/communication and power management
- Reverse-polarity and surge protection for small DC supplies in battery-powered devices
- Low-leakage, high-speed switching applications where fast response is needed
Note: suitable for low to moderate current applications (tens of mA).

SOT-23 (3-pin) package.