SC4910BITSTRT Equivalent & Substitute Parts

Part Overview

The SC4910BITSTRT is a Power Management Integrated Circuit (PMIC) functioning as a secondary-side controller with synchronous rectifier capability in power supply applications. Manufactured by Semtech Corporation, this device operates within a 4.5V to 18V supply voltage range and is housed in a 20-TSSOP surface mount package. The product is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations where legacy component compatibility is required.

Substiute Parts

SC4910BITSTRT

Semtech CorporationIn Stock: 1144SC4910BITSTRT Datasheet

Current PartRFQ

FAN7688SJX

onsemiIn Stock: 1550FAN7688SJX Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SC4910BITSTRT is determined by functional equivalence in the secondary-side controller and synchronous rectifier application domain. The primary substitution criteria are:

• Functional classification as a secondary-side power supply controller with synchronous rectifier capability
• Operating temperature range compatibility (-40°C to 125°C)
• Supply voltage range accommodation (input range must encompass or exceed 4.5V ~ 18V)
• Surface mount packaging suitable for PCB integration
• RoHS compliance status for regulatory alignment
• Moisture sensitivity level compatibility (MSL 1)

The FAN7688SJX from onsemi meets these substitution criteria while offering enhanced specifications in certain parameters, including lower quiescent current consumption and active product status.

Parameter Comparison

Engineering Selection Recommendations

The FAN7688SJX represents a direct functional substitute for the obsolete SC4910BITSTRT in secondary-side power supply controller applications. Selection of the FAN7688SJX is supported by the following engineering factors:

• Active product status ensures long-term availability and manufacturing support
• ROHS3 compliance exceeds the RoHS compliance requirement of the original part
• Identical operating temperature range (-40°C to 125°C) maintains thermal performance specifications
• Extended supply voltage range (0V ~ 18V) provides broader operational flexibility compared to the 4.5V minimum of the SC4910BITSTRT
• Significantly reduced quiescent current (80 µA versus 10 mA) improves power efficiency in standby and low-power operating modes
• Identical moisture sensitivity level (MSL 1) ensures equivalent handling and storage requirements
• Matching ECCN and HTSUS classifications maintain regulatory and trade compliance

Package transition from 20-TSSOP to 16-SOIC requires PCB layout modification and pin-to-pin functional verification during implementation.

Frequently Asked Questions (FAQ)

Q: Can the FAN7688SJX directly replace the SC4910BITSTRT without PCB modifications?

A: Functional substitution is possible; however, package geometry differs (20-TSSOP versus 16-SOIC). PCB layout redesign is required. Pin functionality must be verified against application-specific circuit requirements.

Q: What is the significance of the supply voltage range difference (4.5V ~ 18V versus 0V ~ 18V)?

A: The FAN7688SJX accommodates a lower minimum supply voltage (0V), providing operational flexibility in applications with variable input conditions. The SC4910BITSTRT requires minimum 4.5V. Both devices support the full 18V maximum.

Q: Why is the quiescent current specification important for substitution?

A: The FAN7688SJX operates at 80 µA quiescent current compared to 10 mA for the SC4910BITSTRT. This 125-fold reduction in standby power consumption may improve overall system efficiency, particularly in battery-powered or low-power applications.

Q: Are there compliance differences between the two parts?

A: Both parts are RoHS compliant. The FAN7688SJX carries ROHS3 certification, representing a more recent compliance standard. Both share identical ECCN (EAR99) and HTSUS (8542.39.0001) classifications.

Q: What does the MSL 1 rating mean for both parts?

A: MSL 1 (Moisture Sensitivity Level 1) indicates unlimited shelf life without moisture control requirements. Both the SC4910BITSTRT and FAN7688SJX can be stored and handled under standard industrial conditions without special desiccant packaging.

Q: Is the FAN7688SJX suitable for new designs?

A: Yes. The FAN7688SJX is classified as an active product with current manufacturing support, making it appropriate for new design implementations requiring secondary-side power supply controller functionality.