TLP521 Optoisolator Transistor Output Equivalent & Substitute Parts

Part Overview

The TLP521 is a single-channel optoisolator with transistor output manufactured by Isocom Components 2004 LTD. This 4-DIP through-hole component provides 5300Vrms isolation voltage and is designed for DC input applications requiring galvanic isolation. The part maintains active product status with 2907 units in current inventory. Substitute parts are identified based on matching electrical characteristics, isolation ratings, and mechanical compatibility to ensure direct functional equivalence in circuit applications.

Substiute Parts

TLP521

Isocom Components 2004 LTDIn Stock: 3002TLP521 Datasheet

Current PartRFQ

ISP521-1X

Isocom Components 2004 LTDIn Stock: 45128ISP521-1X Datasheet

Parametric EquivalentRFQ

TLP521-1X

Isocom Components 2004 LTDIn Stock: 2410TLP521-1X Datasheet

Parametric EquivalentRFQ

TLP621XBL

Isocom Components 2004 LTDIn Stock: 2832TLP621XBL Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the TLP521 are qualified based on the following critical parameters that determine functional equivalence:

• Isolation Voltage: 5300Vrms (all substitutes match)
• Number of Channels: 1 (all substitutes match)
• Output Type: Transistor (all substitutes match)
• Current Transfer Ratio Range: 50% to 600% @ 5mA (all substitutes match)
• Maximum Output Voltage: 55V (all substitutes match)
• Maximum Output Current: 50mA per channel (all substitutes match)
• Vce Saturation: 400mV maximum (all substitutes match)
• Operating Temperature Range: -30°C to 100°C (all substitutes match)
• Package / Case: 4-DIP (0.300", 7.62mm) (all substitutes match)
• Mounting Type: Through Hole (all substitutes match)
• Compliance: ROHS3 Compliant, REACH Unaffected (all substitutes match)

The three substitute parts—ISP521-1X, TLP521-1X, and TLP621XBL—maintain identical electrical performance specifications and mechanical compatibility with the TLP521, enabling direct substitution in circuit designs.

Parameter Comparison

Engineering Selection Recommendations

All three substitute parts—ISP521-1X, TLP521-1X, and TLP621XBL—are qualified as direct functional equivalents to the TLP521 based on matching electrical specifications and mechanical compatibility. Selection among these parts may be based on availability and packaging format:

• TLP521-1X maintains identical timing specifications (Turn On/Turn Off Time: 3µs, 3µs) and is available in 2375 units.
• ISP521-1X is available in the highest quantity (45100 units) with matching electrical performance; Turn On/Turn Off Time is not specified in available data.
• TLP621XBL offers improved rise time performance (2µs versus 4µs) and is available in 2743 units.

All parts maintain ROHS3 compliance, REACH unaffected status, and MSL Level 1 (Unlimited) moisture sensitivity rating, meeting regulatory and environmental requirements for industrial applications.

Frequently Asked Questions (FAQ)

Q: Can ISP521-1X be used as a direct replacement for TLP521?

A: Yes. ISP521-1X meets all critical electrical parameters including 5300Vrms isolation voltage, 50-600% current transfer ratio, 55V maximum output voltage, and 50mA output current. Both parts use identical 4-DIP through-hole packaging and operate across the same temperature range (-30°C to 100°C). The only difference is that Turn On/Turn Off Time is not specified for ISP521-1X in available documentation.

Q: What is the difference between TLP521-1X and TLP621XBL?

A: Both parts are electrically equivalent with matching isolation voltage, current transfer ratio, output voltage, and output current specifications. The primary difference is rise time: TLP621XBL has a typical rise time of 2µs compared to 4µs for TLP521-1X. This faster switching characteristic may be beneficial in high-speed applications but does not affect basic functional compatibility.

Q: Are all substitute parts available in the same packaging?

A: Yes. TLP521, ISP521-1X, TLP521-1X, and TLP621XBL all use 4-DIP (0.300", 7.62mm) through-hole packaging. All parts are mounted identically on PCBs and are mechanically interchangeable.

Q: Do all substitute parts meet the same compliance standards?

A: Yes. All parts are ROHS3 compliant, REACH unaffected, and carry MSL Level 1 (Unlimited) moisture sensitivity rating. All parts maintain active product status with Isocom Components 2004 LTD as the manufacturer.

Q: Which substitute part should I select based on availability?

A: ISP521-1X offers the highest inventory level at 45100 units. TLP621XBL provides improved rise time performance (2µs) if switching speed is a design consideration. TLP521-1X maintains complete specification alignment with the original TLP521 part.