ISO7821FDW Equivalent & Substitute Parts

Part Overview

The ISO7821FDW is a General Purpose Digital Isolator manufactured by Texas Instruments, featuring 5700Vrms isolation voltage and 2-channel unidirectional isolation with 100Mbps data rate capability. This device is classified as Active product status and utilizes capacitive coupling technology for signal isolation in industrial and communication applications. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are maintained across the specified parameter set, enabling design flexibility and supply chain alternatives.

Substiute Parts

ISO7821FDW

Texas InstrumentsIn Stock: 1125ISO7821FDW Datasheet

Current PartRFQ

ISO7810FDW

Texas InstrumentsIn Stock: 1304ISO7810FDW Datasheet

Parametric EquivalentRFQ

ISO7821DW

Texas InstrumentsIn Stock: 1246ISO7821DW Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the ISO7821FDW is determined by the following critical parameters:

Primary Substitution Criteria:

• Isolation voltage: 5700Vrms (exact match required)
• Common Mode Transient Immunity: 100kV/µs (exact match required)
• Data rate: 100Mbps (exact match required)
• Propagation delay characteristics: 16ns maximum (exact match required)
• Package type: 16-SOIC form factor (exact match required)
• Supply voltage range: 2.25V ~ 5.5V (exact match required)
• Operating temperature range: -55°C ~ 125°C (exact match required)
• Technology: Capacitive coupling (exact match required)
• Compliance: ROHS3 and REACH status (exact match required)

Variable Parameters Allowing Substitution:

• Number of channels: The ISO7821FDW features 2 channels; the ISO7810FDW provides 1 channel. Channel count reduction is acceptable when application requirements do not demand full 2-channel functionality.
• Input configuration: ISO7821FDW has 1/1 inputs (Side 1/Side 2); ISO7810FDW has 1/0 inputs. Single-channel variants are substitutable for applications requiring unidirectional isolation on one channel only.

The ISO7821DW is a direct parametric equivalent to the ISO7821FDW, maintaining identical electrical and mechanical specifications with no functional differences.

Parameter Comparison

Engineering Selection Recommendations

ISO7821DW: Direct substitution for ISO7821FDW. All electrical parameters, mechanical specifications, and compliance certifications are identical. Selection between these two parts is determined by packaging availability and inventory status only. Both maintain ROHS3 compliance and REACH unaffected status.

ISO7810FDW: Substitution applicable only when application requirements permit single-channel operation. This part maintains all critical electrical performance parameters (isolation voltage, CMTI, data rate, propagation delay, supply voltage, and operating temperature) and identical package form factor. The reduction from 2 channels to 1 channel represents the only functional difference. This substitution is valid for designs requiring unidirectional isolation on a single signal path. All compliance certifications (ROHS3, REACH) and product status (Active) remain equivalent.

Frequently Asked Questions (FAQ)

Q: Can ISO7810FDW replace ISO7821FDW in all applications?

A: No. ISO7810FDW is a single-channel device while ISO7821FDW provides 2-channel isolation. Substitution is valid only when your application requires isolation on one signal channel. If your design requires simultaneous isolation of two independent signal paths, ISO7810FDW is not suitable.

Q: What is the difference between ISO7821FDW and ISO7821DW?

A: These parts are parametric equivalents with identical electrical performance and mechanical specifications. Both feature 2-channel 5700Vrms isolation, 100Mbps data rate, and 16-SOIC packaging. Selection is based on packaging format availability and supply chain considerations.

Q: Are all three parts pin-compatible?

A: ISO7821FDW and ISO7821DW share identical pinouts as 2-channel devices. ISO7810FDW, as a 1-channel device, has a different pin configuration and is not pin-compatible with the 2-channel variants. PCB layout modification is required if substituting ISO7810FDW into a design originally specified for ISO7821FDW.

Q: Do all substitute parts meet the same compliance requirements?

A: Yes. ISO7810FDW and ISO7821DW maintain identical ROHS3 compliance and REACH unaffected status as the ISO7821FDW. Moisture sensitivity level (MSL 2, 1 Year) is consistent across all three parts.

Q: What are the key electrical parameters that must remain constant for substitution?

A: Isolation voltage (5700Vrms), Common Mode Transient Immunity (100kV/µs), data rate (100Mbps), propagation delay (16ns maximum), supply voltage range (2.25V ~ 5.5V), and operating temperature range (-55°C ~ 125°C) must remain unchanged. All substitute parts maintain these specifications.