Is there a pin-compatible replacement for BAS40?

A direct, verified pin-compatible replacement is not listed. Many parts share the BAS40 name with different configurations (e.g., BAS40-05 common cathode). Always check the datasheet pinout against your board layout.

What risks should I check before replacing BAS40?

First, verify the diode technology is Schottky. Second, confirm the pinout; many SOT-23 diodes are dual-diode arrays which are not pin-compatible with a single diode. Finally, ensure voltage and current ratings are equal or greater.

BAS40 Alternatives, Datasheet & Cross Reference | Diotec Semiconductor AG

Finding a substitute for the BAS40 Schottky diode requires careful review of electrical and physical properties. This guide provides analysis of potential alternatives for this SOT-23 general-purpose rectifier.

AI replacement insight

Package riskhigh

Pinout mismatch is the main risk. While the SOT-23 package fits, the internal connections are different for dual-diode arrays.

Electrical riskmedium

Using a standard diode instead of Schottky will increase forward voltage drop and slow switching, impacting circuit performance.

Can it be replaced directly?

No direct pin-for-pin replacement has been identified. Alternatives like BAS40-05 are common-cathode dual diodes and require careful PCB layout verification to ensure compatibility with the single-diode footprint of BAS40.

Best replacement path

Look for other single Schottky diodes in a SOT-23 package with Vr >= 40V and Io >= 200mA. Candidates like BAS40-05 are functionally similar but require pinout verification as they are dual-diode parts.

Main risk

The primary risk is pinout incompatibility. Using a dual-diode part in a single-diode footprint without verifying the layout can lead to a short circuit or an open circuit.

Recommended alternatives

A functional alternative in the same SOT-23 package with identical ratings, but requires pinout verification due to its dual common-cathode configuration.

View details

Alternative comparison matrix

Feature / factor	BAS40	BAS40-05	PMEG4005CT,215	Compatibility / risk
Package	SOT-23	SOT-23	SOT-23 (TO-236AB)	SOT-23 / SOT-23 (TO-236AB) — Package is physically compatible.; PMEG4005CT,215: Package is physically compatible.
Pinout	Single Diode	1 Pair Common Cathode	1 Pair Common Cathode	1 Pair Common Cathode — Pinout differs. Target is a single diode, candidate is a dual common-cathode array. Requires PCB layout verification.; PMEG4005CT,215: Pinout differs. Target is a single diode, candidate is a dual common-cathode array. Requires PCB layout verification.
Voltage	40V	40V	40V	40V — Voltage rating is identical.; PMEG4005CT,215: Voltage rating is identical.
Current	200mA	200mA	500mA	200mA / 500mA — Current rating is identical.; PMEG4005CT,215: Higher current rating provides more margin.
Diode Type	Schottky	Schottky	Schottky	Schottky — Diode technology matches.; PMEG4005CT,215: Diode technology matches.

Application & sourcing insights

Questions & answers

BAS40-05 is a strong candidate as it's a 40V, 200mA Schottky diode in a SOT-23 package. However, it is a dual common-cathode device and requires pinout verification before use.