CAT3604AHV4-T2 Equivalent & Substitute Parts

Part Overview

The CAT3604AHV4-T2 is a LED Driver IC with integrated 4-output DC-DC regulator utilizing switched capacitor (charge pump) topology for backlight applications. Manufactured by onsemi in a 16-TQFN (4x4) package, this component delivers 30mA per channel output current with analog and PWM dimming capabilities. The part is designated as Last Time Buy, indicating end-of-life status. Identifying equivalent substitute parts is necessary to ensure design continuity and maintain supply chain reliability for applications currently utilizing this component.

Substiute Parts

CAT3604AHV4-T2

onsemiIn Stock: 2078CAT3604AHV4-T2 Datasheet

Current PartRFQ

LM27952SD/NOPB

National SemiconductorIn Stock: 8348LM27952SD/NOPB Datasheet

SimilarRFQ

LM27952SDX/NOPB

Texas InstrumentsIn Stock: 1511LM27952SDX/NOPB Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the CAT3604AHV4-T2 are identified based on the following critical parameters that determine functional equivalence:

• Topology: Switched Capacitor (Charge Pump) DC-DC regulator
• Number of Outputs: 4 independent LED driver channels
• Supply Voltage Range: 3V to 5.5V input compatibility
• Output Current per Channel: 30mA minimum capability
• Dimming Control: PWM dimming support
• Operating Temperature Range: -40°C to 85°C
• Application: LED backlight driver
• Internal Switching: Integrated switch functionality

The substitute parts LM27952SD/NOPB and LM27952SDX/NOPB meet these core functional requirements. Both parts maintain the same supply voltage range, output current specification, and operating temperature range. While package geometry differs (14-WSON vs. 16-TQFN), both are surface-mount solutions with exposed pads suitable for thermal management in LED driver applications.

Parameter Comparison

Engineering Selection Recommendations

LM27952SDX/NOPB is the primary substitute candidate. This part is in Active product status, ensuring long-term availability and supply chain stability. It carries ROHS3 compliance and MSL Level 1 rating, matching the environmental and regulatory requirements of the original CAT3604AHV4-T2. The part is available in Tape & Reel packaging, suitable for automated assembly processes.

LM27952SD/NOPB serves as a secondary substitute option. While also functionally equivalent in core parameters, this variant lacks specified RoHS and MSL documentation in the provided data. It remains in Active status with substantial inventory availability.

Both LM27952 variants operate at 750kHz switching frequency compared to the CAT3604AHV4-T2's 1MHz, and support PWM dimming only (lacking the analog dimming capability of the original). These differences do not affect functional substitution for standard LED backlight driver applications. Package geometry changes from 16-TQFN (4x4) to 14-WSON (4x3) require PCB layout modification but maintain surface-mount, exposed-pad thermal design principles.

Frequently Asked Questions (FAQ)

Q: Can LM27952 parts directly replace CAT3604AHV4-T2 without PCB modification?

A: No. The package change from 16-TQFN (4x4) to 14-WSON (4x3) requires PCB footprint redesign. Pin count reduction from 16 to 14 necessitates schematic and layout verification to ensure all required signals are routed correctly.

Q: What is the impact of the 750kHz vs. 1MHz frequency difference?

A: The LM27952 operates at lower switching frequency. This affects filter component selection and EMI characteristics but does not prevent functional substitution for LED backlight applications within the specified current and voltage parameters.

Q: Why does CAT3604AHV4-T2 support analog dimming while LM27952 supports only PWM?

A: The dimming control method difference reflects different IC design approaches. If analog dimming is required for the application, LM27952 substitutes are not suitable. If PWM dimming is acceptable, substitution is valid.

Q: Which LM27952 variant should be selected: SD/NOPB or SDX/NOPB?

A: LM27952SDX/NOPB is recommended. It carries explicit ROHS3 compliance and MSL Level 1 certification, matching the original part's regulatory status. Both are functionally equivalent; the choice depends on supply availability and packaging requirements (Tape & Reel vs. standard packaging).

Q: Are there thermal management differences between the packages?

A: Both packages feature exposed pads for thermal dissipation. The 14-WSON (4x3) is slightly smaller than 16-TQFN (4x4), but both are designed for similar thermal performance in LED driver applications at 30mA per channel.

Q: What is the inventory status for substitutes?

A: LM27952SDX/NOPB has 1,425 units in stock. LM27952SD/NOPB has 8,318 units in stock. Both provide adequate supply for design transitions from the Last Time Buy CAT3604AHV4-T2.