ISO721MMDREP Digital Isolator Equivalent & Substitute Parts

Part Overview

The ISO721MMDREP is a general purpose digital isolator manufactured by Texas Instruments, featuring 4000Vpk isolation voltage, single channel unidirectional configuration, and 150Mbps data rate in an 8-SOIC surface mount package. The device operates across 3V to 5.5V supply range with -55°C to 125°C temperature rating and employs capacitive coupling isolation technology. This part is Active status and ROHS3 compliant. Substitute parts are identified when equivalent functional performance can be achieved within the specified electrical and mechanical parameters of the application.

Substiute Parts

ISO721MMDREP

Texas InstrumentsIn Stock: 3153ISO721MMDREP Datasheet

Current PartRFQ

SI8610AB-B-IS

Skyworks Solutions Inc.In Stock: 842SI8610AB-B-IS Datasheet

MFR RecommendedRFQ

SI8610BC-B-ISR

Skyworks Solutions Inc.In Stock: 6105SI8610BC-B-ISR Datasheet

MFR RecommendedRFQ

SI8610EC-B-ISR

Skyworks Solutions Inc.In Stock: 8036SI8610EC-B-ISR Datasheet

MFR RecommendedRFQ

SI8710CD-B-ISR

Skyworks Solutions Inc.In Stock: 8568SI8710CD-B-ISR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the ISO721MMDREP are grouped based on the following critical parameters that determine functional equivalence:

Primary Substitution Criteria:

• Package type: 8-SOIC surface mount form factor
• Isolation technology: Capacitive coupling
• Channel configuration: Single channel, unidirectional
• Data rate capability: Minimum 150Mbps
• Isolation voltage: Minimum 4000Vpk or equivalent Vrms rating
• Supply voltage compatibility: Overlap with 3V to 5.5V range
• Operating temperature range: Support for -40°C to 125°C minimum

Substitute Classification:

SI8610BC-B-ISR and SI8610EC-B-ISR meet primary substitution criteria with 3750Vrms isolation (equivalent to 5303Vpk), 150Mbps data rate, 8-SOIC package, and 2.5V to 5.5V supply range.

SI8610AB-B-IS provides functional substitution with 2500Vrms isolation (equivalent to 3536Vpk), reduced data rate of 1Mbps, 8-SOIC package, and 2.5V to 5.5V supply range. This part is suitable for applications where lower isolation voltage and data rate are acceptable.

SI8710CD-B-ISR offers substitution with 5000Vrms isolation (equivalent to 7071Vpk), 1Mbps data rate, but differs in package form factor (6-SOIC, 0.295" width) and supply voltage range (3V to 30V), requiring board layout and power supply design verification.

Parameter Comparison

Engineering Selection Recommendations

SI8610BC-B-ISR and SI8610EC-B-ISR are the primary substitutes for ISO721MMDREP. Both parts maintain 150Mbps data rate performance, provide 3750Vrms isolation voltage (exceeding the 4000Vpk requirement when converted), support the required supply voltage range, and are packaged identically in 8-SOIC form factor. Both are Active status and ROHS3 compliant. SI8610BC-B-ISR is available in Tape & Reel packaging with 6007 units in stock, while SI8610EC-B-ISR is also Tape & Reel packaged with 7998 units in stock. These parts are suitable for direct replacement in applications requiring 150Mbps performance.

SI8610AB-B-IS is a secondary substitute suitable only for applications where data rate requirements are reduced to 1Mbps or lower. This part provides 2500Vrms isolation voltage and is available in Tube packaging with 763 units in stock. The reduced propagation delay specification (35ns versus 16ns) and lower data rate limit its use to low-speed communication interfaces.

SI8710CD-B-ISR provides the highest isolation voltage at 5000Vrms but operates at 1Mbps data rate and uses a different package form factor (6-SOIC, 0.295" width). The extended supply voltage range (3V to 30V) and different package dimensions require board layout redesign. This part is suitable only for applications where package footprint change is acceptable and low data rate operation is required. MSL rating of 3 (168 Hours) requires stricter moisture control during storage and assembly.

All substitute parts maintain Active product status and ROHS3 compliance, ensuring long-term availability and regulatory alignment with the original ISO721MMDREP.

Frequently Asked Questions (FAQ)

Q: Can SI8610AB-B-IS replace ISO721MMDREP in all applications?

A: No. SI8610AB-B-IS operates at 1Mbps maximum data rate compared to ISO721MMDREP's 150Mbps capability. This part is suitable only for low-speed applications. Additionally, the isolation voltage is 2500Vrms (3536Vpk equivalent), which is lower than the 4000Vpk specification. Use this substitute only when application requirements permit reduced data rate and isolation voltage.

Q: What is the difference between Vpk and Vrms isolation voltage ratings?

A: Vpk (peak voltage) and Vrms (RMS voltage) are different measurement standards for isolation voltage. The relationship is approximately Vpk = Vrms × √2. SI8610BC-B-ISR and SI8610EC-B-ISR rated at 3750Vrms equal approximately 5303Vpk, which exceeds the ISO721MMDREP's 4000Vpk requirement. SI8710CD-B-ISR rated at 5000Vrms equals approximately 7071Vpk.

Q: Are SI8610BC-B-ISR and SI8610EC-B-ISR functionally identical?

A: Yes. Both parts have identical electrical specifications: 3750Vrms isolation, 150Mbps data rate, 13ns propagation delay, 8-SOIC package, and 2.5V to 5.5V supply range. The difference is packaging format: SI8610BC-B-ISR is supplied in Tape & Reel, while SI8610EC-B-ISR is also Tape & Reel. Both are suitable for direct substitution.

Q: Can SI8710CD-B-ISR be used as a drop-in replacement?

A: No. SI8710CD-B-ISR uses a different package form factor (6-SOIC, 0.295" width versus 8-SOIC, 0.154" width), requiring PCB layout modification. Additionally, the 1Mbps data rate is significantly lower than ISO721MMDREP's 150Mbps. Use this part only when board redesign is acceptable and low-speed operation is required.

Q: What is the impact of different Moisture Sensitivity Levels (MSL)?

A: ISO721MMDREP has MSL 1 (Unlimited shelf life), while SI8610 series parts have MSL 2A (4 weeks) and SI8710CD-B-ISR has MSL 3 (168 hours). Lower MSL ratings require stricter moisture control during storage and assembly. Parts with MSL 2A or 3 must be baked before reflow soldering if shelf life limits are exceeded.

Q: Which substitute offers the best performance match to ISO721MMDREP?

A: SI8610BC-B-ISR and SI8610EC-B-ISR provide the closest performance match, maintaining 150Mbps data rate, identical 8-SOIC package dimensions, and compatible supply voltage range. Both exceed the isolation voltage requirement and are recommended for applications requiring direct functional replacement.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All substitute parts listed (SI8610AB-B-IS, SI8610BC-B-ISR, SI8610EC-B-ISR, and SI8710CD-B-ISR) are ROHS3 compliant, matching the compliance status of ISO721MMDREP.