BQ21040DBVR Equivalent & Substitute Parts

Part Overview

The BQ21040DBVR is an active lithium ion/polymer battery charger IC manufactured by Texas Instruments, designed for single-cell battery charging applications. This SOT-23-6 surface mount device provides constant programmable charging current up to 800mA with integrated fault protection for over-temperature, over-voltage, and short-circuit conditions. The part is ROHS3 compliant and maintains unlimited moisture sensitivity rating (MSL 1). Substitute parts are identified when equivalent electrical performance and mechanical compatibility are required due to inventory constraints, design flexibility, or application-specific requirements.

Substiute Parts

BQ21040DBVR

Texas InstrumentsIn Stock: 31439BQ21040DBVR Datasheet

Current PartRFQ

BQ21040DBVT

Texas InstrumentsIn Stock: 6759BQ21040DBVT Datasheet

Parametric EquivalentRFQ

RT9505GQW

Richtek USA Inc.In Stock: 24084RT9505GQW Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility is determined by the following critical parameters:

Primary Substitution Criteria:

• Battery chemistry compatibility (Lithium Ion/Polymer)
• Single-cell charging capability
• Battery pack voltage (4.2V nominal)
• Fault protection features (minimum: Over Temperature, Over Voltage)
• Surface mount mounting type
• Active product status
• ROHS3 compliance

Parametric Equivalent (BQ21040DBVT): Identical electrical specifications and package type to the main part. Substitution is direct with no design modifications required.

Manufacturer Recommended Alternative (RT9505GQW): Functional equivalent with higher maximum charge current (1.2A vs 800mA) and different package form factor (10-WDFN vs SOT-23-6). Substitution requires PCB layout redesign and thermal management evaluation due to package differences.

Parameter Comparison

Engineering Selection Recommendations

BQ21040DBVT: Direct substitution for BQ21040DBVR. Identical electrical and mechanical specifications with matching SOT-23-6 package. Both parts maintain active product status, ROHS3 compliance, and unlimited moisture sensitivity rating. No design modifications required. Selection based on inventory availability.

RT9505GQW: Functional alternative for applications requiring higher charge current capability (1.2A). Requires PCB redesign due to package change from SOT-23-6 to 10-WDFN (3x3). Operating temperature range differs (−40°C to 85°C ambient vs 0°C to 125°C junction). Short-circuit protection is not included in this device. Moisture sensitivity increases to MSL 3 (168-hour limit). All parts maintain ROHS3 compliance and active product status.

Frequently Asked Questions (FAQ)

Q: Can BQ21040DBVT be used as a direct replacement for BQ21040DBVR?

A: Yes. Both parts are manufactured by Texas Instruments with identical electrical specifications, package type (SOT-23-6), and fault protection features. No PCB modifications are required.

Q: What are the key differences between BQ21040DBVR and RT9505GQW?

A: The RT9505GQW differs in three critical areas: package form factor (10-WDFN vs SOT-23-6), maximum charge current (1.2A vs 800mA), and fault protection (no short-circuit protection). Operating temperature range and moisture sensitivity also differ. PCB redesign is necessary for substitution.

Q: Is RT9505GQW suitable for designs currently using BQ21040DBVR?

A: RT9505GQW is functionally equivalent for single-cell lithium ion charging at 4.2V nominal voltage. However, substitution requires PCB layout redesign due to package differences and thermal management evaluation. The absence of short-circuit protection must be evaluated against application requirements.

Q: What packaging formats are available for these charger ICs?

A: BQ21040DBVR and BQ21040DBVT are supplied in SOT-23-6 surface mount package. RT9505GQW is supplied in 10-WDFN (3x3) surface mount package. Both formats are suitable for automated assembly.

Q: Are all three parts ROHS3 compliant?

A: Yes. BQ21040DBVR, BQ21040DBVT, and RT9505GQW all maintain ROHS3 compliance and REACH unaffected status.

Q: What is the moisture sensitivity difference between these parts?

A: BQ21040DBVR and BQ21040DBVT have MSL 1 (unlimited shelf life). RT9505GQW has MSL 3, requiring storage in controlled humidity conditions with a 168-hour floor life limit after moisture exposure.