Overview
The ISO7221ADR, produced by Texas Instruments, is a dual-channel digital isolator that provides galvanic isolation between two circuits. This device is part of the ISO7221x family and is designed to block high voltages and isolate grounds, preventing noise currents from interfering with sensitive circuitry. The ISO7221ADR features a silicon-dioxide (SiO2) isolation barrier, which ensures up to 4000 VPK of isolation per VDE standards. It is suitable for use in conjunction with isolated power supplies and is characterized for operation over a wide ambient temperature range of –40°C to +125°C.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | SOIC (D) | - |
| Pins | 8 | - |
| Operating Temperature Range | -40 to 125 | °C |
| Signaling Rate Options | 1, 5, 25, 150 Mbps | - |
| Channel-to-Channel Output Skew | 1 ns Max | - |
| Pulse-Width Distortion (PWD) | 1 ns Max | - |
| Jitter Content | 1 ns Typ at 150 Mbps | - |
| Transient Immunity | 50 kV/μs Typ | - |
| Supply Voltages | 2.8 V, 3.3 V, 5 V | - |
| ESD Protection | 4 kV | - |
| Maximum Junction Temperature | 170 | °C |
| Maximum Repetitive Peak Isolation Voltage | 4000 VPK | - |
Key Features
- Galvanic isolation up to 4000 VPK per VDE standards using a silicon-dioxide (SiO2) isolation barrier.
- Low channel-to-channel output skew and pulse-width distortion (1 ns Max).
- Low jitter content (1 ns Typ at 150 Mbps).
- High transient immunity (50 kV/μs Typ).
- Operates with 2.8 V, 3.3 V, or 5 V supplies.
- 4 kV ESD protection.
- High electromagnetic immunity.
- Wide operating temperature range of –40°C to +125°C.
- Safety-related certifications including DIN EN IEC 60747-17, UL 1577, and IEC 61010-1, IEC 62368-1).
Applications
The ISO7221ADR is suitable for various applications requiring high isolation and low noise interference, such as:
- Industrial control systems
- Medical devices
- Automotive systems
- Telecommunications equipment
- Mixed-signal microcontrollers, digital-to-analog converters, and transformer drivers).
Q & A
- What is the primary function of the ISO7221ADR?
The ISO7221ADR is a dual-channel digital isolator that provides galvanic isolation between two circuits, blocking high voltages and isolating grounds to prevent noise interference).
- What are the signaling rate options for the ISO7221ADR?
The ISO7221ADR supports signaling rates of 1, 5, 25, and 150 Mbps).
- What is the maximum operating temperature range for the ISO7221ADR?
The device operates over a temperature range of –40°C to +125°C).
- What are the supply voltage options for the ISO7221ADR?
The device can operate with supply voltages of 2.8 V, 3.3 V, or 5 V).
- What level of ESD protection does the ISO7221ADR offer?
The ISO7221ADR provides 4 kV ESD protection).
- What safety certifications does the ISO7221ADR have?
The device has certifications including DIN EN IEC 60747-17, UL 1577, and IEC 61010-1, IEC 62368-1).
- What is the maximum junction temperature for the ISO7221ADR?
The maximum junction temperature is 170°C).
- How does the ISO7221ADR handle input signal conditioning?
The device conditions the binary input signal, translates it to a balanced signal, and then differentiates it by the capacitive isolation barrier. A differential comparator receives the logic transition information and sets or resets a flip-flop and the output circuit accordingly).
- What happens if the dc-refresh pulse is not received every 4 μs?
If the dc-refresh pulse is not received every 4 μs, the input is assumed to be unpowered or not being actively driven, and the failsafe circuit drives the output to a logic high state).
- What are some common applications for the ISO7221ADR?
The device is commonly used in industrial control systems, medical devices, automotive systems, telecommunications equipment, and with mixed-signal microcontrollers, digital-to-analog converters, and transformer drivers).
