TOP243P Equivalent & Substitute Parts

Part Overview

The TOP243P is an offline switch flyback converter IC manufactured by Power Integrations, part of the TOPSwitch®-GX series. This device integrates a 700V breakdown voltage power switch with frequency control and comprehensive fault protection (current limiting, over-temperature, over-voltage) for isolated flyback topology applications. The TOP243P operates at 66kHz to 132kHz switching frequency with 25W power capability and is housed in an 8-DIP through-hole package.

The TOP243P is classified as Obsolete. Locating equivalent or substitute parts is necessary for ongoing production support, design updates, or when inventory becomes unavailable. Direct substitutes within the TOPSwitch®-GX family maintain electrical and mechanical compatibility while offering improved product status or compliance certifications.

Substiute Parts

TOP243P

Power IntegrationsIn Stock: 12311TOP243P Datasheet

Current PartRFQ

TOP243PN

Power IntegrationsIn Stock: 1602TOP243PN Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the TOP243P is determined by strict alignment with the following critical parameters:

Primary Substitution Criteria:

• Manufacturer: Power Integrations
• Series: TOPSwitch®-GX
• Topology: Flyback
• Output Isolation: Isolated
• Voltage - Breakdown: 700V
• Frequency - Switching: 66kHz ~ 132kHz
• Power (Watts): 25 W
• Duty Cycle: 66.5%
• Fault Protection: Current Limiting, Over Temperature, Over Voltage
• Control Features: Frequency Control
• Operating Temperature: -40°C ~ 150°C (TJ)
• Package / Case: 8-DIP (0.300", 7.62mm), 7 Leads
• Mounting Type: Through Hole

The TOP243PN is a direct substitute for the TOP243P. Both devices share identical electrical specifications, switching characteristics, and thermal operating range. The primary difference is packaging format (Tube vs. standard packaging) and product status classification. The TOP243PN is classified as "Not For New Designs" rather than "Obsolete," indicating improved availability and supply chain status.

Parameter Comparison

Engineering Selection Recommendations

For Existing Production Support: The TOP243P remains available with substantial inventory (12,300 units). This part is suitable for sustaining production of existing designs where component qualification and PCB layout are already established.

For New Designs or Design Revisions: The TOP243PN is the preferred selection. Although classified as "Not For New Designs," it offers superior compliance status (RoHS Compliant vs. RoHS non-compliant) and represents a more current product designation within the TOPSwitch®-GX family. The TOP243PN maintains 100% electrical and mechanical compatibility with the TOP243P, requiring no circuit modifications or PCB redesign.

Compliance Considerations: The TOP243PN's RoHS compliance status provides regulatory advantage for applications subject to RoHS directives. Both parts carry REACH Unaffected status and EAR99 export classification.

Frequently Asked Questions (FAQ)

Q: Can TOP243PN be used as a direct replacement for TOP243P in existing designs?

A: Yes. The TOP243PN is electrically and mechanically identical to the TOP243P. No circuit modifications, PCB layout changes, or firmware updates are required. The devices are pin-compatible and share identical electrical characteristics, switching frequency range, power rating, and thermal specifications.

Q: What is the difference between TOP243P and TOP243PN?

A: The primary differences are: (1) Product Status—TOP243P is Obsolete; TOP243PN is Not For New Designs; (2) RoHS Compliance—TOP243P is non-compliant; TOP243PN is compliant; (3) Packaging Format—TOP243P uses standard packaging; TOP243PN uses Tube packaging. Electrical performance and package footprint are identical.

Q: Are there other TOPSwitch®-GX alternatives to TOP243P?

A: The TOP243PN data indicates cross-references to STR-A6069H, TOP244PN, TOP245PN, TOP246PN, and TOP242PN. However, these parts are listed as substitutes for TOP243PN, not direct equivalents to TOP243P. Substitution to these alternative models requires verification of different electrical specifications (power rating, switching frequency, or duty cycle) and may necessitate circuit redesign.

Q: What is the through-hole package specification for TOP243P?

A: The TOP243P is housed in an 8-DIP package with 0.300" (7.62mm) pitch and 7 leads. This is a standard through-hole package compatible with conventional PCB assembly processes. The TOP243PN uses the identical package specification.

Q: Is the TOP243P suitable for new product development?

A: No. The TOP243P is classified as Obsolete. For new designs, the TOP243PN is the appropriate selection within the TOPSwitch®-GX family, offering improved product status and RoHS compliance.

Q: What fault protection features does TOP243P include?

A: The TOP243P integrates three fault protection mechanisms: Current Limiting (protects against overcurrent conditions), Over Temperature protection (disables operation if junction temperature exceeds limits), and Over Voltage protection (prevents damage from supply voltage transients).