LNK6779E Equivalent & Substitute Parts

Part Overview

The LNK6779E is an offline switch flyback converter IC from Power Integrations' LinkSwitch™-HP series, designed for isolated power supply applications. This Active product operates at 120kHz to 136kHz switching frequency with 153W power capability and 725V breakdown voltage rating. The component is packaged in eSIP-7C (7-SSIP) through-hole configuration with internal current limiting, overload, over-temperature, over-voltage, and short-circuit protection. Substitute parts are identified when equivalent functional performance can be achieved within the allowed electrical and mechanical parameter ranges for offline flyback converter applications.

Substiute Parts

LNK6779E

Power IntegrationsIn Stock: 720LNK6779E Datasheet

Current PartRFQ

LNK6769E

Power IntegrationsIn Stock: 5644LNK6769E Datasheet

Parametric EquivalentRFQ

LNK6777E

Power IntegrationsIn Stock: 3138LNK6777E Datasheet

Parametric EquivalentRFQ

LNK6778E

Power IntegrationsIn Stock: 3496LNK6778E Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LNK6779E is determined by equivalence in the following critical parameters:

Mandatory Equivalence Criteria:

• Topology: Flyback
• Output Isolation: Isolated
• Switching Frequency: 120–136 kHz
• Package / Case: 7-SSIP, 6 Leads, Exposed Pad, Formed Leads (eSIP-7C)
• Mounting Type: Through Hole
• Fault Protection: Current Limiting, Over Load, Over Temperature, Over Voltage, Short Circuit
• Series: LinkSwitch™-HP
• Manufacturer: Power Integrations
• Operating Temperature Range: −40°C to +150°C (TJ)
• RoHS Compliance: RoHS Compliant
• MSL Rating: 1 (Unlimited)

Allowable Variation Parameters:

• Voltage - Breakdown: 650V to 725V (application-dependent)
• Power (Watts): 117W to 153W (application-dependent)
• Duty Cycle: 64% (fixed across all variants)

The LNK6779E, LNK6777E, LNK6778E, and LNK6769E share identical topology, package, frequency, protection features, and compliance status. Differences in breakdown voltage and power rating allow selection based on specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

LNK6779E (Primary Reference): 153W power rating with 725V breakdown voltage. Select for applications requiring maximum power delivery within the LinkSwitch™-HP series at high input voltage tolerance.

LNK6777E: 117W power rating with 725V breakdown voltage. Select for lower-power applications where 725V breakdown voltage is required but power demand does not exceed 117W.

LNK6778E: 135W power rating with 725V breakdown voltage. Select for mid-range power applications requiring 725V breakdown voltage rating between LNK6777E and LNK6779E specifications.

LNK6769E: 153W power rating with 650V breakdown voltage. Select for applications where input voltage stress does not exceed 650V and 153W power delivery is required. This variant offers equivalent power capability to LNK6779E at reduced voltage rating.

All four parts maintain identical topology, switching frequency, package configuration, fault protection features, operating temperature range, and compliance certifications. Selection between parts is determined solely by application requirements for breakdown voltage and power rating.

Frequently Asked Questions (FAQ)

Q: Can LNK6769E replace LNK6779E in all applications?

A: LNK6769E is electrically equivalent to LNK6779E in power rating (153W) and switching characteristics. The difference is breakdown voltage: LNK6769E is rated 650V while LNK6779E is rated 725V. Substitution is valid only if the application input voltage stress does not exceed 650V. If the design requires 725V breakdown voltage margin, LNK6779E must be used.

Q: What is the difference between LNK6777E and LNK6778E?

A: Both parts share 725V breakdown voltage and identical switching frequency, topology, and package. The difference is power rating: LNK6777E is rated 117W and LNK6778E is rated 135W. Select LNK6777E for applications requiring up to 117W output power; select LNK6778E for applications requiring 117W to 135W output power.

Q: Are all four parts pin-compatible?

A: Yes. All four parts (LNK6779E, LNK6777E, LNK6778E, LNK6769E) use identical 7-SSIP package with 6 leads, exposed pad, and formed leads (eSIP-7C). Pin configuration and through-hole mounting are identical, allowing direct PCB substitution without layout modification.

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

A: Yes. All four parts are RoHS Compliant, carry MSL Rating 1 (Unlimited), and hold Active product status. REACH and ECCN classifications are identical across all variants.

Q: What determines whether a part is a valid substitute?

A: Valid substitution requires equivalence in topology (Flyback), isolation (Isolated), switching frequency (120–136 kHz), package (7-SSIP eSIP-7C), mounting type (Through Hole), fault protection features, operating temperature range (−40°C to +150°C), and compliance status. Power rating and breakdown voltage may vary based on application requirements.

Q: Can LNK6779E be used in place of LNK6777E?

A: Yes. LNK6779E (153W, 725V) can replace LNK6777E (117W, 725V) in any application. The higher power rating and identical breakdown voltage make LNK6779E a direct functional upgrade. No design changes are required.