OP755D Phototransistor 935nm Side View Radial Equivalent & Substitute Parts

Part Overview

The OP755D is a phototransistor optical sensor manufactured by TT Electronics/Optek Technology, designed for 935nm infrared detection in side view radial configuration. This component is classified as obsolete, making equivalent substitute parts necessary for ongoing design support and procurement continuity. The OP755D operates across industrial temperature ranges and is suitable for applications requiring through-hole mounting with radial package geometry.

Substiute Parts

OP755D

TT Electronics/Optek TechnologyIn Stock: 790OP755D Datasheet

Current PartRFQ

LTR-301

Lite-On Inc.In Stock: 269158LTR-301 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the OP755D is determined by the following critical parameters:

• Wavelength compatibility: The OP755D operates at 935nm. The LTR-301 operates at 940nm, representing a 5nm variance within the near-infrared spectrum suitable for phototransistor applications.
• Mounting and orientation: Both parts require through-hole mounting with side view radial package configuration.
• Electrical ratings: Collector-emitter breakdown voltage (30 V maximum) and dark current (100 nA maximum) must be maintained or exceeded.
• Environmental compliance: RoHS3 compliance and MSL rating of 1 are required for substitution eligibility.

The LTR-301 qualifies as a manufacturer-recommended substitute based on these alignment criteria.

Parameter Comparison

Engineering Selection Recommendations

The LTR-301 is the active substitute for the obsolete OP755D. Both components maintain identical collector-emitter breakdown voltage (30 V) and dark current specifications (100 nA maximum). Both are ROHS3 compliant with MSL rating of 1, ensuring regulatory and environmental compatibility.

Design considerations for substitution:

• The LTR-301 maximum collector current is 2.4 mA compared to the OP755D at 30 mA. Circuit designs must accommodate this reduced current capacity.
• The LTR-301 maximum power dissipation is 100 mW versus the OP755D at 200 mW. Thermal management requirements may differ.
• The LTR-301 operating temperature range extends to 85°C maximum, compared to the OP755D at 100°C. Applications requiring operation above 85°C require design review.
• Wavelength difference of 5nm (935nm to 940nm) is within acceptable tolerance for most infrared detection applications using phototransistors.

Frequently Asked Questions (FAQ)

Q: Can the LTR-301 directly replace the OP755D in existing designs?

A: Direct replacement is possible if circuit designs accommodate the LTR-301 maximum collector current of 2.4 mA and maximum power dissipation of 100 mW. Designs requiring higher current or power dissipation require circuit modification.

Q: What is the significance of the 5nm wavelength difference between 935nm and 940nm?

A: Both wavelengths operate in the near-infrared spectrum suitable for phototransistor applications. The 5nm variance is within typical tolerance for infrared detection circuits. Application-specific spectral response requirements should be evaluated against component datasheets.

Q: Are both parts suitable for industrial temperature applications?

A: The OP755D operates across -40°C to 100°C. The LTR-301 operates across -40°C to 85°C. Applications requiring operation above 85°C must use the OP755D or identify alternative components with extended temperature ratings.

Q: Do both parts meet current regulatory requirements?

A: Both the OP755D and LTR-301 are ROHS3 compliant with MSL rating of 1 (unlimited moisture sensitivity level). Both are suitable for applications subject to RoHS and REACH regulations.

Q: What packaging considerations apply to substitution?

A: Both components use radial through-hole packages with side view orientation. Physical footprint and lead configuration are identical, allowing direct PCB layout compatibility without modification.