OPB991N55Z Equivalent & Substitute Parts

Part Overview

The OPB991N55Z is a through-beam optical sensor from the Photologic® series manufactured by TT Electronics/Optek Technology. This sensor features a 0.125" (3.18mm) sensing distance with NPN open collector buffer output, designed for chassis mount applications with wire leads. The part is currently classified as obsolete, making equivalent substitute parts necessary for ongoing system maintenance and new design implementations. Active alternatives within the OPB991 base product family provide direct functional compatibility while maintaining current manufacturing support.

Substiute Parts

OPB991N55Z

TT Electronics/Optek TechnologyIn Stock: 1176OPB991N55Z Datasheet

Current PartRFQ

OPB991L11Z

TT Electronics/Optek TechnologyIn Stock: 1005OPB991L11Z Datasheet

MFR RecommendedRFQ

OPB991L51Z

TT Electronics/Optek TechnologyIn Stock: 2335OPB991L51Z Datasheet

MFR RecommendedRFQ

OPB991L55Z

TT Electronics/Optek TechnologyIn Stock: 1232OPB991L55Z Datasheet

MFR RecommendedRFQ

OPB991P11Z

TT Electronics/Optek TechnologyIn Stock: 1072OPB991P11Z Datasheet

MFR RecommendedRFQ

OPB991P51Z

TT Electronics/Optek TechnologyIn Stock: 1759OPB991P51Z Datasheet

MFR RecommendedRFQ

OPB991T11Z

TT Electronics/Optek TechnologyIn Stock: 2692OPB991T11Z Datasheet

MFR RecommendedRFQ

OPB991T51Z

TT Electronics/Optek TechnologyIn Stock: 5301OPB991T51Z Datasheet

MFR RecommendedRFQ

OPB991T55Z

TT Electronics/Optek TechnologyIn Stock: 4563OPB991T55Z Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the OPB991N55Z are selected from the active OPB991 base product family. All substitute candidates maintain identical electrical and mechanical specifications across the following critical parameters:

• Sensing distance: 0.125" (3.18mm)
• Sensing method: Through-beam
• Output configuration: NPN open collector with buffer
• Supply voltage range: 4.5V ~ 16V
• Supply current: 12 mA
• Response time: 70ns
• Operating temperature range: -40°C ~ 70°C
• Mounting type: Chassis mount
• Package type: Module with wire leads
• RoHS3 compliance and REACH unaffected status

The OPB991 family variants differ only in packaging configuration (bulk versus tape/reel) and internal component sourcing designations, which do not affect functional performance or electrical characteristics. All listed substitutes are active products with current manufacturing support and documented inventory availability.

Parameter Comparison

Engineering Selection Recommendations

All substitute parts listed are active products manufactured by TT Electronics/Optek Technology and maintain full ROHS3 compliance with REACH unaffected status, matching the regulatory posture of the obsolete OPB991N55Z. The substitutes provide direct functional equivalence with no electrical or mechanical deviations.

For new designs or system replacements, OPB991T51Z and OPB991T55Z are recommended based on highest current inventory availability (5218 and 4526 units respectively), ensuring supply chain continuity. OPB991L51Z (2283 units) and OPB991T11Z (2671 units) provide secondary options with substantial stock levels.

All variants within the OPB991 family are interchangeable at the circuit level. Selection among available substitutes should be based on packaging requirements, lead time considerations, and supplier inventory status rather than electrical performance criteria.

Frequently Asked Questions (FAQ)

Q: Are all OPB991 variants electrically identical to the OPB991N55Z?

A: Yes. All listed substitutes maintain identical electrical specifications including supply voltage (4.5V ~ 16V), supply current (12 mA), response time (70ns), sensing distance (0.125"), and output configuration (NPN open collector buffer). Functional performance in circuit applications is equivalent.

Q: What differentiates the part number suffixes (L, P, T) in the OPB991 family?

A: The letter designations indicate internal component sourcing and packaging configuration variants. These differences do not affect electrical characteristics, sensing performance, or mechanical compatibility. All variants are functionally interchangeable.

Q: Can OPB991 substitutes be used in existing designs originally specified for OPB991N55Z?

A: Yes. The identical electrical specifications, operating temperature range (-40°C ~ 70°C), supply voltage tolerance (4.5V ~ 16V), and chassis mount wire lead package ensure direct compatibility in existing circuit designs without modification.

Q: Are there any compliance or certification differences between the obsolete OPB991N55Z and active substitutes?

A: No. All substitute parts maintain ROHS3 compliance and REACH unaffected status identical to the original part. Regulatory and environmental compliance requirements are satisfied across all variants.

Q: Which substitute part offers the best supply availability?

A: OPB991T51Z provides the highest inventory level at 5218 units, followed by OPB991T55Z at 4526 units. Both options ensure reliable supply chain access for immediate and future procurement needs.