VOS618A-7T Optoisolator: Equivalent & Substitute Parts

Part Overview

The VOS618A-7T is an active optoisolator manufactured by Vishay Semiconductor Opto Division, designed for high-voltage isolation applications. This single-channel phototransistor output device provides 3750Vrms isolation in a 4-SSOP surface mount package. The part is currently in active production status with 1073 units in stock. Substitute parts are necessary to address supply chain flexibility, alternative packaging requirements, or performance grade selection within the same electrical and mechanical specifications.

Substiute Parts

VOS618A-7T

Vishay Semiconductor Opto DivisionIn Stock: 1108VOS618A-7T Datasheet

Current PartRFQ

VOS618A-7X001T

Vishay Semiconductor Opto DivisionIn Stock: 4191VOS618A-7X001T Datasheet

Parametric EquivalentRFQ

EL3H7(A)(EA)-G

Everlight Electronics Co LtdIn Stock: 2858EL3H7(A)(EA)-G Datasheet

MFR RecommendedRFQ

EL3H7(A)-G

Everlight Electronics Co LtdIn Stock: 2115EL3H7(A)-G Datasheet

MFR RecommendedRFQ

EL3H7(B)(TA)-VG

Everlight Electronics Co LtdIn Stock: 1519EL3H7(B)(TA)-VG Datasheet

MFR RecommendedRFQ

EL3H7(B)-G

Everlight Electronics Co LtdIn Stock: 1683EL3H7(B)-G Datasheet

MFR RecommendedRFQ

EL3H7(EA)-VG

Everlight Electronics Co LtdIn Stock: 3901EL3H7(EA)-VG Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the VOS618A-7T is determined by strict equivalence across the following critical parameters:

• Voltage isolation rating: 3750Vrms (mandatory match)
• Output type: Transistor (mandatory match)
• Maximum output voltage: 80V (mandatory match)
• Maximum output current: 50mA (mandatory match)
• Operating temperature range: -55°C ~ 110°C (mandatory match)
• Package type: 4-SOIC / 4-SSOP (mandatory match)
• Mounting type: Surface Mount (mandatory match)
• Input type: DC (mandatory match)

Substitute parts are grouped into two categories:

Parametric Equivalent: VOS618A-7X001T (Vishay) — identical electrical specifications and packaging, alternative internal configuration.

Manufacturer Recommended Equivalents: EL3H7 series variants (Everlight Electronics) — meet all mandatory electrical and mechanical parameters with variations in Current Transfer Ratio grades and packaging formats.

Parameter Comparison

Engineering Selection Recommendations

All substitute parts listed maintain active product status and ROHS3 compliance, meeting regulatory requirements equivalent to the VOS618A-7T.

VOS618A-7X001T (Vishay): Direct parametric equivalent with identical electrical performance. Recommended for applications requiring Vishay manufacturer continuity. Higher inventory availability (4100 units) supports supply chain stability.

EL3H7(A)(EA)-G and EL3H7(A)-G (Everlight): Grade A performance with 80–160% Current Transfer Ratio range. Suitable for standard isolation applications. Available in Tape & Reel and Tube packaging. Vce Saturation reduced to 200mV compared to VOS618A-7T (400mV), indicating improved output transistor efficiency.

EL3H7(B)(TA)-VG and EL3H7(B)-G (Everlight): Grade B performance with 130–260% Current Transfer Ratio range. Provides higher gain margin for applications requiring enhanced output drive capability. Available in Cut Tape/Digi-Reel and Tube packaging.

EL3H7(EA)-VG (Everlight): Extended performance grade with 50–600% Current Transfer Ratio range. Broadest gain specification for applications with variable input current conditions. Highest inventory (3852 units) in Tape & Reel format.

All Everlight variants exhibit faster fall time (3µs vs. 7µs) and lower Vce Saturation (200mV vs. 400mV), representing improved switching performance characteristics within the same isolation and output specifications.

Frequently Asked Questions (FAQ)

Q: Can EL3H7 series parts directly replace VOS618A-7T in existing designs?

A: Yes. All EL3H7 variants meet the mandatory electrical and mechanical parameters: 3750Vrms isolation, 80V maximum output voltage, 50mA output current, 4-SOIC package, and -55°C to 110°C operating range. Differences in Current Transfer Ratio grades and switching times do not affect pin compatibility or basic functional operation.

Q: What is the difference between Current Transfer Ratio grades?

A: Current Transfer Ratio (CTR) defines the output collector current relative to input LED current. Grade A (80–160%) provides standard performance. Grade B (130–260%) offers higher gain. Extended grade (50–600%) covers the widest input current range. Selection depends on circuit design requirements for input current levels and output drive capability.

Q: How do packaging format differences affect substitution?

A: Tape & Reel (TR), Tube, and Cut Tape (CT) formats are handling and delivery methods only. All formats contain identical 4-SOIC components. Selection is based on assembly process requirements and order quantities, not electrical compatibility.

Q: Why do Everlight parts show lower Vce Saturation than Vishay?

A: Vce Saturation (200mV vs. 400mV) reflects output transistor design differences. Lower saturation voltage indicates reduced voltage drop across the output transistor, resulting in improved efficiency and heat dissipation. This is a performance advantage within the same 80V maximum rating.

Q: Are all parts ROHS3 compliant?

A: Yes. VOS618A-7T, VOS618A-7X001T, and all EL3H7 variants are ROHS3 compliant with MSL 1 (Unlimited) moisture sensitivity rating, meeting equivalent environmental and regulatory standards.

Q: What is the significance of Turn On/Turn Off Time specifications?

A: VOS618A-7T specifies 5µs turn-on and 8µs turn-off times. Everlight EL3H7 variants do not publish these parameters but specify 5µs rise time and 3µs fall time, indicating comparable or faster switching performance. Applications with strict timing requirements should reference detailed datasheets for precise switching behavior.