ISO7221MD Digital Isolator Equivalent & Substitute Parts

Part Overview

The ISO7221MD is a general purpose digital isolator manufactured by Texas Instruments, featuring 2500Vrms isolation voltage, 2 channels, and 150Mbps data rate in an 8-SOIC package. This device is classified as Last Time Buy, indicating limited availability and the necessity to identify equivalent alternatives for ongoing design requirements and production planning.

Digital isolators in this category serve critical functions in applications requiring galvanic isolation between logic circuits operating at different voltage domains. The ISO7221MD's capacitive coupling technology, combined with its high common mode transient immunity (25kV/µs) and fast propagation delay (16ns), makes it suitable for industrial and automotive applications.

Key Parameters

Parameter	Value
Manufacturer Part Number	ISO7221MD
Manufacturer	Texas Instruments
Technology	Capacitive Coupling
Number of Channels	2
Voltage - Isolation	2500Vrms
Data Rate	150Mbps
Common Mode Transient Immunity (Min)	25kV/µs
Propagation Delay tpLH / tpHL (Max)	16ns / 16ns
Voltage - Supply	3V ~ 5.5V
Package / Case	8-SOIC (0.154", 3.90mm Width)
Operating Temperature	-40°C ~ 125°C
RoHS Status	ROHS3 Compliant
Product Status	Last Time Buy

Substitute Part Grouping Explanation

Substitution of the ISO7221MD is determined by the following critical parameters:

Primary Substitution Criteria:

Isolation voltage: 2500Vrms (mandatory match)
Number of channels: 2 (mandatory match)
Package type: 8-SOIC (mandatory match for PCB compatibility)
Common mode transient immunity: 25kV/µs (mandatory match)
Supply voltage range: Must encompass 3V ~ 5.5V
Operating temperature range: Must support -40°C ~ 125°C or equivalent industrial range

Secondary Considerations:

Data rate: 150Mbps or higher acceptable
Propagation delay: Lower or equal values acceptable
Technology platform: Capacitive, magnetic, or GMR coupling acceptable if primary criteria met
RoHS and REACH compliance: ROHS3 Compliant and REACH Unaffected required

Substitutes are grouped into three categories: direct manufacturer alternatives (same base product with different packaging), parametric equivalents (different channel count or data rate), and cross-manufacturer alternatives (different technology platform with equivalent electrical performance).

Parameter Comparison

Part Number	Manufacturer	Channels	Isolation (Vrms)	Data Rate (Mbps)	CMTI (kV/µs)	tpLH/tpHL (ns)	Supply (V)	Temp Range (°C)	Status	Package
ISO7221MD	Texas Instruments	2	2500	150	25	16/16	3.0-5.5	-40 to 125	Last Time Buy	8-SOIC
ISO7221MDR	Texas Instruments	2	2500	150	25	16/16	3.0-5.5	-40 to 125	Active	8-SOIC
ADUM1201ARZ	Analog Devices Inc.	2	2500	1	25	150/150	2.7-5.5	-40 to 105	Active	8-SOIC
ADUM1201BRZ	Analog Devices Inc.	2	2500	10	25	50/50	2.7-5.5	-40 to 105	Active	8-SOIC
ADUM1201CRZ	Analog Devices Inc.	2	2500	25	25	45/45	2.7-5.5	-40 to 105	Active	8-SOIC
IL 611-3E	NVE Corp/Isolation Products	2	2500	100	15	15/15	3.0-5.5	-40 to 85	Active	8-SOIC
ISO721MD	Texas Instruments	1	2500	150	25	16/16	3.0-5.5	-40 to 125	Last Time Buy	8-SOIC
ISO722MD	Texas Instruments	1	2500	150	25	16/16	3.0-5.5	-40 to 125	Obsolete	8-SOIC

Engineering Selection Recommendations

Direct Replacement (Recommended Primary Path):

ISO7221MDR is the manufacturer-recommended direct substitute for ISO7221MD. Both devices are identical in electrical specifications and package configuration. ISO7221MDR carries Active product status with higher inventory availability (5853 pcs vs. 860200 pcs for the original), ensuring long-term supply continuity. The only difference is packaging format: ISO7221MDR is supplied in Cut Tape (CT) & Digi-Reel format versus Tube for ISO7221MD. Both maintain ROHS3 compliance and REACH Unaffected status.

Cross-Manufacturer Alternatives (Active Status):

The ADUM1201 series from Analog Devices Inc. provides 2-channel, 2500Vrms isolation in 8-SOIC packages with Active product status. Three speed grades are available:

ADUM1201ARZ: 1Mbps (lowest speed, longest propagation delay 150ns)
ADUM1201BRZ: 10Mbps (mid-range, 50ns propagation delay)
ADUM1201CRZ: 25Mbps (highest speed, 45ns propagation delay)

These devices employ magnetic coupling technology versus the ISO7221MD's capacitive coupling. All ADUM1201 variants support extended supply voltage range (2.7V-5.5V) but operate to 105°C maximum versus 125°C for ISO7221MD. Selection depends on application data rate requirements: ADUM1201CRZ at 25Mbps approaches ISO7221MD performance but does not reach 150Mbps specification.

IL 611-3E from NVE Corp uses GMR (Giant Magnetoresistive) technology with 100Mbps data rate and 15kV/µs CMTI. This device is suitable for applications not requiring the full 150Mbps bandwidth of ISO7221MD but needing faster response than ADUM1201 series. Operating temperature maximum is 85°C, limiting use in extended industrial temperature applications.

Single-Channel Alternatives (Not Recommended for Direct Substitution):

ISO721MD and ISO722MD are single-channel variants with identical electrical performance to ISO7221MD but reduced channel count. These are suitable only for applications requiring single-channel isolation and represent design changes rather than direct substitution.

Frequently Asked Questions (FAQ)

Q: Can ISO7221MDR be used as a direct drop-in replacement for ISO7221MD?

A: Yes. ISO7221MDR is electrically and mechanically identical to ISO7221MD. The only difference is packaging format (Cut Tape & Digi-Reel versus Tube). Both fit the same PCB footprint and require no design modifications. ISO7221MDR is the manufacturer-recommended substitute with Active product status.

Q: What is the key difference between ISO7221MD and ADUM1201 series?

A: The primary difference is data rate and coupling technology. ISO7221MD operates at 150Mbps using capacitive coupling with 16ns propagation delay. ADUM1201 series uses magnetic coupling with lower data rates (1Mbps to 25Mbps) and longer propagation delays (45ns to 150ns). ADUM1201CRZ at 25Mbps is the fastest ADUM1201 variant but still significantly slower than ISO7221MD. Selection depends on application bandwidth requirements.

Q: Are ADUM1201 devices suitable replacements for high-speed applications?

A: ADUM1201CRZ at 25Mbps is insufficient for applications requiring ISO7221MD's 150Mbps performance. ADUM1201 series is appropriate only for lower-bandwidth applications. IL 611-3E at 100Mbps provides intermediate performance but still falls short of 150Mbps specification.

Q: What is the operating temperature limitation when using ADUM1201 or IL 611-3E?

A: ADUM1201 series operates to 105°C maximum, and IL 611-3E to 85°C maximum, versus ISO7221MD's 125°C. Applications requiring full -40°C to 125°C industrial temperature range must use ISO7221MD or ISO7221MDR. ADUM1201 and IL 611-3E are limited to -40°C to 105°C and -40°C to 85°C respectively.

Q: Is the 8-SOIC package identical across all listed substitutes?

A: Yes. All listed parts use 8-SOIC (0.154", 3.90mm Width) package with identical pin assignments for 2-channel configurations. PCB footprints are compatible. Packaging format (Tube, Cut Tape, or Digi-Reel) affects supply and handling but not electrical or mechanical compatibility.

Q: What compliance certifications apply to all substitute options?

A: All listed parts are ROHS3 Compliant and REACH Unaffected. Regulatory compliance is maintained across all substitutes. Verify specific application requirements for additional certifications (automotive AEC-Q100, industrial certifications, etc.) as these are not specified in the provided data.

Q: Why is ISO721MD listed as a substitute if it has only 1 channel?

A: ISO721MD is a parametric equivalent sharing identical electrical specifications and package type but with reduced channel count. It is not a direct substitute for 2-channel applications but represents an alternative for designs requiring single-channel isolation with identical performance characteristics.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message