RB520S-30 Equivalent & Substitute Parts

Part Overview

The RB520S-30 is a Schottky diode manufactured by Taiwan Semiconductor Corporation, designed for surface mount applications in the SOD-523F package. This component operates at a maximum reverse voltage of 30V with an average rectified current of 200mA, making it suitable for low-voltage rectification and switching applications. The part is currently in active production status with 557,300 units in stock. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are required due to component availability, supply chain considerations, or design flexibility within specified parameter ranges.

Substiute Parts

RB520S-30

Taiwan Semiconductor CorporationIn Stock: 557377RB520S-30 Datasheet

Current PartRFQ

RB521S30T5G

onsemiIn Stock: 50196RB521S30T5G Datasheet

SimilarRFQ

RB751S40T5G

onsemiIn Stock: 1982RB751S40T5G Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the RB520S-30 is determined by the following critical parameters:

Primary Substitution Criteria:

• Voltage - DC Reverse (Vr) (Max): Must equal or exceed 30V
• Package / Case: Must be SC-79 or SOD-523 for mechanical compatibility
• Mounting Type: Must be Surface Mount
• Technology: Must be Schottky diode technology
• RoHS Status: Must maintain ROHS3 compliance

Secondary Compatibility Factors:

• Current - Average Rectified (Io): Substitute parts must support the required current level or higher
• Operating Temperature Range: Must encompass the application's thermal requirements
• Voltage - Forward (Vf): Lower forward voltage indicates improved efficiency; higher values remain acceptable if within circuit design margins

The identified substitute parts RB521S30T5G and RB751S40T5G meet the primary substitution criteria through matching reverse voltage ratings, identical package specifications, and equivalent Schottky technology. Differences in forward voltage characteristics and reverse leakage current reflect manufacturing variations within the Schottky diode category and do not preclude functional substitution.

Parameter Comparison

Engineering Selection Recommendations

RB521S30T5G (onsemi): This substitute maintains electrical equivalence to the RB520S-30 with identical reverse voltage (30V) and average rectified current (200mA) ratings. The forward voltage is reduced to 500 mV @ 200 mA, representing improved efficiency characteristics. Both parts operate within the same temperature range (-55°C to 125°C) and maintain ROHS3 compliance. This substitute is suitable for direct replacement in applications where the RB520S-30 is specified, provided circuit design accommodates the lower forward voltage drop. Inventory availability is 50,145 units.

RB751S40T5G (onsemi): This substitute shares the 30V reverse voltage rating and SOD-523 package specification with the RB520S-30. However, the average rectified current is rated at 30mA, which is significantly lower than the 200mA requirement of the main part. This substitute is applicable only in circuits where the actual current demand does not exceed 30mA, regardless of the main part's 200mA rating. The extended operating temperature range (-55°C to 150°C) and superior reverse leakage characteristics (500 nA @ 30 V) provide advantages in specific thermal environments. Inventory availability is 1,970 units.

Both substitute parts maintain active product status and full regulatory compliance (ROHS3, REACH Unaffected, EAR99 ECCN classification).

Frequently Asked Questions (FAQ)

Q: Can RB521S30T5G replace RB520S-30 in all applications?

A: RB521S30T5G is electrically and mechanically compatible with RB520S-30. Both parts share identical reverse voltage (30V), average rectified current (200mA), and operating temperature range (-55°C to 125°C). The lower forward voltage (500 mV vs. 600 mV @ 200 mA) in RB521S30T5G represents improved performance. Substitution is valid for direct replacement in circuit designs specified for RB520S-30.

Q: When is RB751S40T5G suitable as a substitute?

A: RB751S40T5G is suitable only when the circuit's actual current requirement does not exceed 30mA. Although the part shares the 30V reverse voltage rating and SOD-523 package with RB520S-30, its 30mA current rating is insufficient for applications requiring the full 200mA capability of the main part. This substitute is appropriate for low-current switching or rectification circuits operating within its current specification.

Q: Are all three parts mechanically interchangeable?

A: Yes. RB520S-30, RB521S30T5G, and RB751S40T5G all use the SC-79/SOD-523 surface mount package. Mechanical interchangeability is confirmed for PCB layout and reflow soldering processes. Electrical performance differences must be evaluated based on circuit requirements.

Q: What are the key differences in forward voltage characteristics?

A: RB520S-30 specifies 600 mV @ 200 mA forward voltage. RB521S30T5G reduces this to 500 mV @ 200 mA, indicating lower power dissipation at equivalent current levels. RB751S40T5G specifies 370 mV @ 1 mA, reflecting its lower current rating. Forward voltage differences affect power efficiency and thermal performance in rectification circuits.

Q: Do all substitute parts maintain regulatory compliance?

A: Yes. RB520S-30, RB521S30T5G, and RB751S40T5G are all ROHS3 compliant and REACH unaffected. All parts carry EAR99 ECCN classification and HTSUS code 8541.10.0070. Regulatory compliance is maintained across all three options.

Q: What is the significance of reverse leakage current differences?

A: RB520S-30 specifies 1 µA @ 10 V reverse leakage. RB521S30T5G increases to 30 µA @ 10 V, while RB751S40T5G reduces to 500 nA @ 30 V. Lower reverse leakage improves circuit performance in high-impedance applications and reduces standby power consumption. Higher leakage values remain acceptable in standard rectification circuits where leakage current is not a limiting factor.

Q: Can RB751S40T5G be used in a 200mA circuit?

A: No. RB751S40T5G is rated for 30mA average rectified current. Using this part in a 200mA circuit exceeds its current specification and results in device failure or degraded performance. Current rating must match or exceed the circuit's actual operating current.

Q: What is the temperature operating range difference?

A: RB520S-30 and RB521S30T5G operate from -55°C to 125°C. RB751S40T5G extends the upper limit to 150°C. The extended range in RB751S40T5G provides advantages in high-temperature environments but does not affect substitution decisions for standard temperature applications.