Spark Logic

BAT54S Schottky diode pinout

Series pair Schottky configuration in SOT-23. onsemi documents top code L44.

BAT54A · SOT-23 3 contacts
BAT54 · SOT-23 3 contacts
BAT54C · SOT-23 3 contacts

BAT54S · SOT-23

3 contacts Current package
BAT54AW · SOT-323 3 contacts
BAT54W · SOT-323 3 contacts
BAT54CW · SOT-323 3 contacts
BAT54SW · SOT-323 3 contacts

onsemi / Diodes Incorporated / PANJIT · Series pair; onsemi top code L44.

BAT54S · SOT-23 pinout

BAT54S · SOT-23
Top view, single lead at the top. Pin 1 is lower left, pin 2 lower right and pin 3 at the top.
Selected pin details

1 · A1

Terminal · Bidirectional

Anode of D1.

onsemi BAT54/D Rev. 3, p. 1 Connection Diagram

Electrical limits · Link to this pin

Verify polarity with a meter

Verify polarity with a meterPin 1 · anodePin 3 · cathodePin 3 · anodePin 2 · cathode
  • Pin 1
    • D1 anode
  • Pin 2
    • D2 cathode
  • Pin 3
    • D1 cathode
    • D2 anode

Connection guide

All 3 pins

PinSignalDirectionFunction
1A1 TerminalTerminal Anode of D1.
2K2 TerminalTerminal Cathode of D2.
3K1/A2 TerminalTerminal Cathode of D1; Anode of D2.

Signal assignments

Diode junctions

Check the individual forward paths before fitting the part. The four suffixes have distinct internal connections.

Electrical limits

ParameterLimitConditions and source
Repetitive reverse voltage30 V absolute maximum30 V absolute maximum Stress rating at TA = 25 °C unless otherwise noted. onsemi BAT54/D Rev. 3, pp. 1–2
Forward voltage320 mV max at 1 mA; 400 mV max at 10 mA320 mV max at 1 mA; 400 mV max at 10 mA TA = 25 °C. Meter readings depend on the instrument current. onsemi BAT54/D Rev. 3, pp. 1–2, Electrical Characteristics
Reverse leakage2 µA max2 µA max VR = 25 V at TA = 25 °C. onsemi BAT54/D Rev. 3, pp. 1–2, Electrical Characteristics

Models and documents

L42 is documented for onsemi BAT54A and Diodes BAT54ATA in SOT-23, and PANJIT BAT54AW in SOT-323. All three have a 1+2 lead pattern. Check the package body size and confirm forward conduction from pin 3 to both pins 1 and 2. The N 8 characters do not establish the manufacturer or date.

BAT54S
onsemi order code for the series pair configuration.
BAT54S_D87Z
onsemi order code for the series pair configuration.
BAT54STA
Diodes Incorporated SOT-23. Marking: L44.