S201ERP Equivalent & Substitute Parts

Part Overview

The S201ERP is a thyristor (SCR) rated for 200V off-state voltage with 1A RMS current capacity in a TO-92 through-hole package. Manufactured by Littelfuse Inc., this component is classified as obsolete, making equivalent and higher-rated substitute parts necessary for new designs and production continuity. The S201ERP operates across the industrial temperature range of -40°C to 125°C and complies with RoHS3 standards.

Substiute Parts

S201ERP

Littelfuse Inc.In Stock: 923S201ERP Datasheet

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S401ERP

LittelfuseIn Stock: 995S401ERP Datasheet

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S601ERP

Littelfuse Inc.In Stock: 821S601ERP Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the S201ERP are selected based on electrical and mechanical compatibility within the following criteria:

Gate trigger voltage (Vgt Max): 1.5 V — must match exactly Gate trigger current (Igt Max): 10 mA — must match exactly On-state voltage (Vtm Max): 1.6 V — must match exactly Hold current (Ih Max): 30 mA — must match exactly Operating temperature range: -40°C to 125°C — must match exactly Mounting type: Through Hole — must match exactly Package: TO-92 — must match exactly SCR Type: Standard Recovery — must match exactly

Off-state voltage (Vds) and on-state current (It RMS) may be equal to or greater than the original specification, provided all other parameters remain within tolerance. The substitute parts S401ERP and S601ERP meet these criteria with higher voltage ratings (400V and 600V respectively), making them suitable for applications requiring the same control characteristics with enhanced voltage headroom.

Parameter Comparison

Engineering Selection Recommendations

The S201ERP is obsolete and no longer in active production. Both S401ERP and S601ERP are active products from Littelfuse Inc. and provide direct functional substitution with identical control characteristics.

S401ERP (400V rating) is suitable for applications where the circuit voltage does not exceed 400V. This part provides a 2× voltage margin over the original S201ERP specification.

S601ERP (600V rating) is suitable for applications where higher voltage transient immunity is required or where circuit voltage may reach 600V. This part provides a 3× voltage margin over the original S201ERP specification.

Both substitute parts maintain identical gate trigger thresholds, on-state voltage drops, hold currents, and thermal operating ranges. Both are RoHS3 compliant and available in active inventory. Selection between S401ERP and S601ERP depends solely on the maximum voltage the SCR must withstand in the target application.

Frequently Asked Questions (FAQ)

Q: Can S401ERP or S601ERP be used as direct replacements for S201ERP?

A: Yes. Both parts are direct functional substitutes. They share identical gate trigger voltage, gate trigger current, on-state voltage, hold current, operating temperature range, mounting type, and package. The higher off-state voltage ratings provide additional design margin.

Q: What is the difference between S401ERP and S601ERP?

A: The primary difference is off-state voltage rating: S401ERP is rated for 400V while S601ERP is rated for 600V. All other electrical and mechanical parameters are identical. Selection depends on the maximum voltage the circuit must block.

Q: Are there any packaging differences between these parts?

A: All three parts use the TO-92 through-hole package with formed leads (TO-226-3, TO-92-3 TO-226AA). S401ERP and S601ERP are supplied in Tape & Reel packaging, while S201ERP was supplied in standard packaging. The physical component dimensions and pin configuration are identical.

Q: Do S401ERP and S601ERP have the same gate drive requirements as S201ERP?

A: Yes. Gate trigger voltage (Vgt Max) is 1.5V and gate trigger current (Igt Max) is 10 mA for all three parts. Existing gate drive circuits require no modification.

Q: Are both substitute parts RoHS compliant?

A: Yes. S401ERP and S601ERP are both RoHS3 compliant, matching the compliance status of the original S201ERP.