RT9166-33GX Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The RT9166-33GX is an active linear voltage regulator IC manufactured by Richtek USA Inc., designed to deliver a fixed 3.3V output at 300mA in a surface-mount SOT-89-3 package. This component is classified as a Power Management (PMIC) device and is currently in active product status with 13,555 units in stock. Linear voltage regulators of this specification are essential in applications requiring stable, low-noise power distribution for microcontrollers, sensors, and analog circuits. Equivalent and substitute parts are identified based on matching electrical performance parameters and mechanical compatibility within the same package footprint.

Substiute Parts

RT9166-33GX

Richtek USA Inc.In Stock: 13663RT9166-33GX Datasheet

Current PartRFQ

AP130-33YG-13

Diodes IncorporatedIn Stock: 2111AP130-33YG-13 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the RT9166-33GX are identified based on the following critical parameters that determine functional equivalence:

• Fixed output voltage of 3.3V
• Output current capability of 300mA
• Maximum input voltage of 5.5V
• Surface-mount SOT-89-3 package compatibility
• Operating temperature range of -40°C to 85°C
• Active product status and regulatory compliance (ROHS3)

The AP130-33YG-13 manufactured by Diodes Incorporated meets all these core substitution criteria. Both devices share identical output voltage, current rating, input voltage specification, and package footprint, enabling direct functional replacement in circuit designs.

Parameter Comparison

Engineering Selection Recommendations

Both the RT9166-33GX and AP130-33YG-13 are active, ROHS3-compliant linear voltage regulators suitable for 3.3V / 300mA applications. Selection between these parts should be based on the following considerations:

The RT9166-33GX offers superior dropout voltage performance at 0.23V typical, making it preferable in applications with limited input voltage headroom or where efficiency is critical. The AP130-33YG-13 provides lower quiescent current consumption (100 µA versus 300 µA) and includes short-circuit protection as an additional safeguard, along with improved PSRR characteristics at 58dB. Both devices maintain identical electrical ratings for output voltage, current, and input voltage specifications, ensuring functional interchangeability within the specified operating temperature range.

Frequently Asked Questions (FAQ)

Q: Can the AP130-33YG-13 be used as a direct replacement for the RT9166-33GX?

A: Yes. Both devices deliver 3.3V at 300mA in an identical SOT-89-3 package with matching input voltage and operating temperature specifications. The electrical performance differences (dropout voltage, quiescent current, and PSRR) do not prevent functional substitution; however, circuit performance characteristics will differ slightly.

Q: What is the significance of the voltage dropout difference between these parts?

A: The RT9166-33GX has a lower dropout voltage (0.23V typical) compared to the AP130-33YG-13 (0.5V). In applications where the input voltage is close to the minimum required level, the lower dropout voltage of the RT9166-33GX ensures more reliable regulation. The AP130-33YG-13 requires a higher input voltage margin to maintain stable output.

Q: Are there package compatibility concerns when substituting these parts?

A: No. Both parts use the TO-243AA package designation (SOT-89-3), which is a three-pin surface-mount package. PCB footprints and soldering requirements are identical, enabling direct board-level substitution without layout modifications.

Q: How do the quiescent current specifications affect circuit design?

A: The AP130-33YG-13 draws 100 µA quiescent current compared to 300 µA for the RT9166-33GX. In battery-powered or low-power standby applications, the AP130-33YG-13 reduces parasitic power consumption. For standard line-powered applications, this difference is typically negligible.

Q: What additional protection does the AP130-33YG-13 provide?

A: The AP130-33YG-13 includes short-circuit protection in addition to over-current and over-temperature protection. The RT9166-33GX provides over-current and over-temperature protection. Short-circuit protection adds an extra layer of fault tolerance in the AP130-33YG-13.

Q: Are both parts compliant with current regulatory standards?

A: Yes. Both the RT9166-33GX and AP130-33YG-13 are ROHS3 compliant and REACH unaffected, meeting current environmental and hazardous substance regulations for electronic components.