KA3524 Equivalent & Substitute Parts

Part Overview

The KA3524 is a multi-topology DC-DC controller IC manufactured by onsemi, designed for buck, flyback, and push-pull regulator applications. It functions as a transistor driver for step-down and step-up/step-down topologies with positive, isolation-capable output configuration. The device operates from 8V to 40V supply voltage with a 350kHz switching frequency and 45% maximum duty cycle.

The KA3524 is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. Identifying compatible alternatives ensures design continuity and supply chain reliability.

Substiute Parts

KA3524

onsemiIn Stock: 1062KA3524 Datasheet

Current PartRFQ

SG3524N

STMicroelectronicsIn Stock: 44642SG3524N Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the KA3524 are identified based on the following critical parameters that determine functional compatibility:

• Supply voltage range: 8V ~ 40V
• Output type: Transistor driver
• Duty cycle maximum: 45%
• Package type: 16-DIP through-hole
• Operating temperature range: 0°C ~ 70°C
• Switching frequency capability: 300kHz or higher
• Output configuration: Positive output with isolation capability
• Topology support: Flyback and push-pull configurations

The SG3524N from STMicroelectronics meets these core substitution criteria. While it supports flyback and push-pull topologies (rather than the full buck, flyback, push-pull set), it maintains identical supply voltage range, duty cycle specification, package format, and operating temperature range. The SG3524N operates at 300kHz switching frequency, which is compatible with applications designed for the KA3524's 350kHz specification.

Parameter Comparison

Engineering Selection Recommendations

The SG3524N represents a direct functional substitute for the KA3524 in flyback and push-pull topologies. Both devices share identical electrical specifications for supply voltage range, duty cycle, operating temperature, and package format, enabling direct pin-compatible replacement in through-hole applications.

The SG3524N carries Last Time Buy status, indicating limited future availability. For new designs requiring long-term supply assurance, component selection should prioritize devices with active production status where available.

The SG3524N is ROHS3 compliant, meeting current environmental and regulatory requirements. The KA3524's compliance status is not specified in available documentation.

The 50kHz difference in switching frequency (SG3524N at 300kHz versus KA3524 at 350kHz) does not preclude substitution, as both frequencies fall within standard DC-DC controller operating ranges and are compatible with typical power stage designs.

Frequently Asked Questions (FAQ)

Q: Can the SG3524N directly replace the KA3524 in all applications?

A: The SG3524N is compatible with flyback and push-pull topologies. If your application uses buck topology exclusively, verify that the SG3524N's supported topologies meet your circuit requirements. Both devices share identical package, supply voltage, duty cycle, and operating temperature specifications.

Q: What is the significance of the switching frequency difference?

A: The KA3524 operates at 350kHz while the SG3524N operates at 300kHz. This 50kHz difference is within acceptable margins for most power conversion applications and does not prevent substitution. Verify that your power stage design accommodates the SG3524N's frequency specification.

Q: Are there pin-compatibility concerns between these devices?

A: Both the KA3524 and SG3524N use 16-DIP through-hole packages with identical physical dimensions (0.300", 7.62mm). Pin compatibility should be verified against specific datasheet pinouts before implementation.

Q: What does "Last Time Buy" status mean for the SG3524N?

A: Last Time Buy indicates that STMicroelectronics has announced the end of production for this device. Existing inventory may be available, but future procurement should not rely on continued availability. Consider long-term supply planning accordingly.

Q: How do the output configurations differ?

A: The KA3524 specifies "Positive, Isolation Capable" output configuration, while the SG3524N specifies "Positive" output configuration. The SG3524N supports the positive output requirement. Verify isolation capability requirements in your specific application design.