ISP521-4BL Equivalent & Substitute Parts

Part Overview

The ISP521-4BL is a quad-channel optoisolator with transistor output manufactured by Isocom Components 2004 LTD. This 16-pin DIP component provides galvanic isolation up to 5300Vrms across four independent channels, each capable of switching 50mA at up to 55V output. The part is classified as Active status with full RoHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when all critical electrical and mechanical parameters match the original specification, enabling direct replacement in circuit designs without functional compromise.

Substiute Parts

ISP521-4BL

Isocom Components 2004 LTDIn Stock: 669ISP521-4BL Datasheet

Current PartRFQ

ISP521-4XBL

Isocom Components 2004 LTDIn Stock: 1297ISP521-4XBL Datasheet

Parametric EquivalentRFQ

TLP521-4XBL

Isocom Components 2004 LTDIn Stock: 940TLP521-4XBL Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the ISP521-4BL are qualified based on strict equivalence across the following critical parameters:

• Number of Channels: 4 channels required
• Voltage - Isolation: 5300Vrms minimum
• Current Transfer Ratio: 200% minimum @ 1mA
• Output Type: Transistor output configuration
• Voltage - Output (Max): 55V or greater
• Current - Output / Channel: 50mA or greater
• Vce Saturation (Max): 400mV or less
• Operating Temperature Range: -30°C to 100°C minimum
• Package / Case: 16-DIP (0.300", 7.62mm) form factor
• Mounting Type: Through Hole
• RoHS Status: ROHS3 Compliant

Two substitute parts meet these criteria: ISP521-4XBL and TLP521-4XBL. Both maintain identical electrical performance and mechanical compatibility with the original ISP521-4BL specification.

Parameter Comparison

Engineering Selection Recommendations

All three parts—ISP521-4BL, ISP521-4XBL, and TLP521-4XBL—carry Active product status and maintain full RoHS3 compliance with REACH Unaffected classification. Selection between these parts is based on availability and supply chain considerations rather than functional or compliance differences. The ISP521-4XBL and TLP521-4XBL are direct parametric equivalents suitable for immediate substitution in applications currently using the ISP521-4BL. Inventory levels vary across part numbers; selection should account for lead time and stock availability for production requirements.

Frequently Asked Questions (FAQ)

Q: Can ISP521-4XBL replace ISP521-4BL in existing designs?

A: Yes. The ISP521-4XBL is a parametric equivalent with identical electrical specifications, isolation voltage, output current rating, and 16-DIP package form factor. No circuit modifications are required.

Q: What is the difference between ISP521-4BL and TLP521-4XBL?

A: Both parts share identical electrical performance across all critical parameters including isolation voltage, current transfer ratio, output ratings, and operating temperature range. The primary difference is the series designation (ISP521-4 versus TLP521-4). Both are manufactured by Isocom Components 2004 LTD and are fully compatible substitutes.

Q: Are all three parts pin-compatible?

A: Yes. All three parts use the 16-DIP (0.300", 7.62mm) through-hole package with identical pin assignments for quad-channel transistor output optoisolators.

Q: Do these parts require different PCB layouts?

A: No. The identical 16-DIP package footprint and through-hole mounting type ensure direct PCB compatibility without layout modifications.

Q: Are there any compliance or certification differences?

A: No. All three parts maintain identical RoHS3 compliance, REACH Unaffected status, and MSL 1 (Unlimited) moisture sensitivity rating.

Q: Which part should I select if all are available?

A: Selection should be based on supply chain availability, lead time, and inventory levels. All three parts are functionally and mechanically equivalent for direct substitution.