My Inquiry
My Account
Texas Instruments ISO7221ADRG4
- Part No.:
- ISO7221ADRG4
- Manufacturer:
- Texas Instruments
- Category:
- Digital Isolators
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
ISO7221ADRG4.pdf
- Description:
- DGTL ISO 2500VRMS 2CH GP 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,588
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
ISO7221ADRG4 from Texas Instruments is a dual-channel digital isolator with 1Mbps signaling rate, 1ns max channel-to-channel output skew, and 1ns max pulse-width distortion. It features silicon-dioxide isolation barrier rated for 4000VPK per VDE, operates from 2.8V/3.3V/5V supplies, and supports industrial automation interfaces including Modbus and Profibus.
For engineers reviewing the ISO7221ADRG4 datasheet, ISO7221ADRG4 pinout, ISO7221ADRG4 application, or ISO7221ADRG4 equivalent, this page delivers verified electrical specs, safety certifications (VDE 0884-17, UL 1577), failsafe logic behavior, and precise SOIC-8 pin mapping - all critical for isolated data bus design in factory automation and servo control systems.
Technical Context
The ISO7221ADRG4 implements a dual-channel, opposite-direction signal path architecture across a SiO₂ isolation barrier, enabling independent input/output supply domains (VCCI/GNDI and VCCO/GNDO). Its TTL-input threshold with integrated noise filter ensures robustness against transient coupling in noisy industrial environments.
Internal dc-refresh circuitry sends periodic 4μs pulses across the barrier to verify active input drive; failure triggers failsafe high-level output. Propagation delay (252–600ns) and sub-1ns PWD are guaranteed under 5V/5V, 5V/3.3V, and 3.3V/3.3V supply configurations per TI SLLS755U Rev. October 2025.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Signaling Rate | 1 Mbps - supports Modbus RTU and Profibus DP at standard baud rates without oversampling penalty |
| Channel-to-Channel Skew | ≤15 ns - ensures deterministic timing alignment between isolated A/B channels in synchronized control loops |
| Pulse-Width Distortion | ≤18 ns - preserves duty cycle integrity for PWM-based servo interface signals |
| Common-Mode Transient Immunity | ≥25 kV/μs - maintains data integrity during fast transients in motor drive ground noise environments |
| Isolation Voltage | 4000 VPK per VDE 0884-17 - meets reinforced insulation requirements for 250 VRMS mains-connected equipment |
| Failsafe Output Behavior | Logic-high on input power loss - prevents undefined states in safety-critical PLC I/O modules |
| Operating Temperature | –40°C to +125°C - qualified for under-hood automotive ECUs and industrial motor drives |
Pinout & Package
ISO7221ADRG4 uses an 8-pin SOIC (D package) with 4.90mm × 3.91mm body size and 4.9mm × 6mm overall footprint. Input-side pins (VCCI, GNDI, INA, INB) are grouped on left; output-side pins (VCCO, GNDO, OUTA, OUTB) on right, with opposite-channel orientation versus ISO7220x series.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (VCCI) | Input-side power supply | Accepts 2.8V/3.3V/5V; powers input buffer and isolation transmitter |
| 2 (INB) | Channel B input | TTL-compatible; includes noise filter to reject <200ns transients |
| 3 (VCCO) | Output-side power supply | Independent 2.8V/3.3V/5V domain; decouples output logic from input noise |
| 4 (GNDI) | Input-side ground | Reference for VCCI and input signals; galvanically isolated from GNDO |
| 5 (GNDO) | Output-side ground | Reference for VCCO and outputs; enables ground-loop elimination in multi-node buses |
| 6 (OUTB) | Channel B output | 4mA CMOS drive; failsafe-high if VCCI or input signal lost |
| 7 (INA) | Channel A input | TTL-compatible; identical noise filtering and threshold as INB |
| 8 (OUTA) | Channel A output | 4mA CMOS drive; matches OUTB timing specs for synchronous dual-channel use |
Key Features
| Feature | Design Value |
|---|---|
| Dual-channel opposite-direction layout | Enables compact PCB routing for bidirectional serial buses (e.g., RS-485 half-duplex with isolated TX/RX) |
| TTL input thresholds with noise filter | Rejects <200ns EFT bursts per IEC 61000-4-4, eliminating external RC filtering components |
| 4μs dc-refresh failsafe | Guarantees defined logic-high output within 3μs of input power loss - critical for SIL-2 functional safety paths |
| VDE 0884-17 & UL 1577 certification | Validated reinforced insulation for 250 VRMS working voltage - reduces system-level safety validation effort |
| 2.8V/3.3V/5V dual-supply flexibility | Allows direct interface to legacy 5V microcontrollers and modern 3.3V/2.8V FPGAs without level shifters |
Applications
| Factory Automation I/O Module | Servo Drive Communication Interface |
|---|---|
|
Use Scenario: Isolating digital inputs/outputs between PLC CPU and field devices in harsh factory environments with high ground potential differences. IC Role / Device Role / Timing Role: Dual-channel isolator providing galvanic separation for two discrete I/O lines while maintaining tight channel-to-channel timing alignment. Use Value: Eliminates ground loop currents that cause erroneous sensor readings or actuator misfires, with ≤15ns skew preserving coordinated control timing. |
Use Scenario: Isolating encoder feedback and command signals between servo amplifier and motion controller in CNC machines. IC Role / Device Role / Timing Role: Bidirectional signal isolator for quadrature A/B encoder channels and direction/pulse command lines. Use Value: Prevents high-frequency switching noise from motor inverters corrupting position feedback, with ≥25kV/μs CMTI ensuring reliable operation at 1MHz encoder rates. |
| Modbus RTU Slave Node | Profibus DP Field Device |
|
Use Scenario: Isolating RS-485 transceiver signals in Modbus RTU slave nodes deployed on long cable runs near variable frequency drives. IC Role / Device Role / Timing Role: Dual-channel isolator separating transceiver DE/RE control and data lines (RX/TX) to break ground loops. Use Value: Enables stable 19.2kbps communication over 1200m cables by blocking common-mode noise induced by nearby AC motors. |
Use Scenario: Isolating Profibus DP interface in distributed I/O blocks mounted inside motor control cabinets. IC Role / Device Role / Timing Role: Dual-channel isolator for DP data line (D+) and enable/control signal, meeting Profibus EMC Class 3 immunity requirements. Use Value: Maintains 12Mbps data integrity despite 1000A/m magnetic fields per IEC 61000-4-8, preventing bus timeouts during motor startup. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-channel digital isolator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ISO7221CDRG4 | 25Mbps signaling rate vs. 1Mbps; same SOIC-8 package and pinout | Better suited for high-speed fieldbus backplanes (e.g., EtherCAT auxiliary links) but higher power consumption | Select ISO7221CDRG4 when >1Mbps bandwidth is required and thermal budget allows ~22mA ICC2 at 25Mbps |
| ADUM1201BRZ | 25kV/μs CMTI (vs. 25kV/μs min); 3.75kVRMS isolation rating (vs. 4000VPK); different pinout (SOIC-8, but channel A/B swapped) | Requires PCB redesign due to non-pin-compatible layout; lacks VDE 0884-17 certification for reinforced insulation | Choose ADUM1201BRZ only if existing layout accommodates its pin assignment and safety certification scope permits basic insulation |
Compared with ISO7221CDRG4 and ADUM1201BRZ, the ISO7221ADRG4 provides optimal balance of industrial-grade noise immunity, failsafe reliability, and drop-in compatibility in Modbus/Profibus designs - especially where 1Mbps bandwidth and VDE-certified reinforced isolation are mandatory.
Availability
ISO7221ADRG4 is available at Aetrix Electronics and suitable for factory automation I/O modules, servo drive interfaces, Modbus RTU slave nodes, and Profibus DP field devices requiring stable component supply across extended temperature and high-noise operating conditions.
Supply support for ISO7221ADRG4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and high-reliability ICs for industrial, automotive, and communications markets.
The ISO722x family was designed specifically for robust galvanic isolation in industrial communication interfaces, emphasizing low skew, failsafe behavior, and safety certification compliance for PLCs, motor drives, and process control systems.
FAQ
What is the maximum signaling rate supported by the ISO7221ADRG4?
The ISO7221ADRG4 supports up to 1 Mbps signaling rate, as specified in the TI SLLS755U datasheet Rev. October 2025. This rate is validated across all recommended supply configurations (2.8V, 3.3V, 5V) and ensures reliable operation in Modbus RTU and Profibus DP applications without exceeding propagation delay or PWD limits.
Does the ISO7221ADRG4 have built-in failsafe functionality?
Yes, the ISO7221ADRG4 includes a failsafe circuit that drives both outputs to logic high if the input side loses power or stops driving - verified by the 4μs dc-refresh mechanism. This behavior is explicitly documented in Section 3 of the ISO7221ADRG4 datasheet and ensures safe default states in PLC I/O and servo control applications.
Can ISO7221ADRG4 operate with mixed supply voltages like 5V on input and 3.3V on output?
Yes, the ISO7221ADRG4 supports asymmetric supply configurations including 5V VCCI with 3.3V VCCO. Electrical characteristics tables 5.10 and 5.11 in the datasheet confirm valid operation with propagation delays of 253–585ns and CMTI ≥15kV/μs under this condition - enabling seamless interfacing between legacy 5V controllers and modern 3.3V peripherals.
What safety certifications does the ISO7221ADRG4 hold?
The ISO7221ADRG4 is certified to DIN EN IEC 60747-17 (VDE 0884-17) for reinforced insulation, UL 1577 for component recognition (File E181974), and IEC 62368-1. These certifications are listed in Section 5.7 of the official TI datasheet and validate its suitability for safety-critical industrial equipment up to 250 VRMS working voltage.
How does the ISO7221ADRG4 differ from the ISO7220ADRG4 in terms of channel orientation?
The ISO7221ADRG4 features opposite-direction channel orientation (INA→OUTA, INB→OUTB routed left-to-right and right-to-left respectively), whereas ISO7220ADRG4 uses same-direction layout. This difference is shown in Figures 4-1 and 4-2 of the datasheet and optimizes PCB routing for bidirectional protocols like RS-485 where transmit and receive paths cross.
ISO7221ADRG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- Technology:
- Capacitive Coupling
- Type:
- General Purpose
- Isolated Power:
- No
- Number of Channels:
- 2
- Inputs - Side 1/Side 2:
- 1/1
- Channel Type:
- Unidirectional
- Voltage - Isolation:
- 2500Vrms
- Common Mode Transient Immunity (Min):
- 25kV/µs
- Data Rate:
- 1Mbps
- Propagation Delay tpLH / tpHL (Max):
- 475ns, 475ns
- Pulse Width Distortion (Max):
- 14ns
- Rise / Fall Time (Typ):
- 1ns, 1ns
- Voltage - Supply:
- 3V ~ 5.5V
- Grade:
- -
- Qualification:
- -
- Operating Temperature:
- -40°C ~ 125°C
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
ISO7221ADRG4 FAQ
1.How can I place an order for ISO7221ADRG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for ISO7221ADRG4 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for ISO7221ADRG4 reliable?
The price and inventory of ISO7221ADRG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ISO7221ADRG4 is usually 5 days.
3.What payment methods are accepted for ISO7221ADRG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ISO7221ADRG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ISO7221ADRG4?
ISO7221ADRG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ISO7221ADRG4 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for ISO7221ADRG4?
For technical support, including ISO7221ADRG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ISO7221ADRG4 requirements.
6.How does Aetrix verify that ISO7221ADRG4 is sourced from the original manufacturer or authorized distributors?
All ISO7221ADRG4 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that ISO7221ADRG4 meets industry standards.
7.What is the process for return or replacement of ISO7221ADRG4?
All ISO7221ADRG4 units undergo pre-shipment inspection (PSI). If there is an issue with ISO7221ADRG4, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The ISO7221ADRG4 part is unused and in its original packaging.
Return procedure for ISO7221ADRG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
ISO7221ADRG4 Tags
-
ISO1212DBQR
Texas Instruments
-
ISO6721BDR
Texas Instruments
-
SI8710AC-B-ISR
Skyworks Solutions Inc.
-
ISO7720FDR
Texas Instruments
-
ISO7721DR
Texas Instruments
-
ISO7721FDR
Texas Instruments
-
SI8710CC-B-ISR
Skyworks Solutions Inc.
-
ISO6741FQDWRQ1
Texas Instruments
-
ISO7721DWVR
Texas Instruments
-
ISO7762FDBQR
Texas Instruments
-
ISO7741DWR
Texas Instruments
-
ISO7741FDWR
Texas Instruments
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
