Overview
The ISO122U, manufactured by Texas Instruments (formerly Burr-Brown), is a precision analog isolation amplifier designed to provide high accuracy and reliability in various industrial and measurement applications. This device features a unique digital modulation technique to transmit the input signal across a high-voltage differential capacitive barrier, ensuring excellent isolation and signal integrity. The ISO122U is suitable for a wide range of applications, including industrial process control, thermocouple and RTD measurements, and ground loop elimination.
Key Specifications
| Parameter | Unit | Min | Max | |
|---|---|---|---|---|
| Supply Voltage Range | V | ±4.5 | ±18 | |
| Quiescent Current (VS1) | mA | ±5 | ±7 | |
| Quiescent Current (VS2) | mA | ±5.5 | ±7 | |
| Input Offset Voltage | mV | 20.0 | ||
| Gain Error | %FSR | ±0.05 | ±0.50 | |
| Gain vs Temperature | ppm/°C | ±10 | ||
| Nonlinearity | % | 0.020% | ||
| Signal Bandwidth | kHz | 50 | ||
| Isolation Voltage | Vrms | 1500 | ||
| Isolation Mode Rejection | dB | 140 | ||
| Operating Temperature Range | °C | -25 | 85 | |
| Storage Temperature Range | °C | -40 | 125 |
Key Features
- Galvanic Isolation: The ISO122U provides high-voltage differential capacitive isolation, ensuring excellent reliability and high-frequency transient immunity.
- Digital Modulation: The input signal is transmitted digitally across the isolation barrier, enhancing signal integrity.
- Low Nonlinearity: Maximum nonlinearity of 0.020% ensures high accuracy in measurements.
- Wide Supply Range: Operates with supply voltages from ±4.5 V to ±18 V.
- High Isolation Mode Rejection: 140 dB at 60 Hz, ensuring minimal interference.
- Fixed Unity Gain Configuration: Simplifies circuit design and operation.
- Low Quiescent Current: Quiescent currents of ±5 mA on VS1 and ±5.5 mA on VS2.
Applications
- Industrial Process Control: Suitable for transducer isolation, thermocouples, RTDs, pressure bridges, and flow meters.
- Ground Loop Elimination: Effective in eliminating ground loops in various measurement systems.
- Motor and SCR Control: Used in motor and SCR control applications where isolation is critical.
- Power Monitoring: Ideal for power monitoring and measurement systems.
- PC-Based Data Acquisition: Used in PC-based data acquisition systems for accurate and isolated measurements.
- Test Equipment: Employed in test equipment to ensure isolated and precise measurements.
Q & A
- What is the supply voltage range of the ISO122U?
The ISO122U operates with supply voltages ranging from ±4.5 V to ±18 V. - What is the maximum nonlinearity of the ISO122U?
The maximum nonlinearity is 0.020%. - What is the isolation voltage rating of the ISO122U?
The isolation voltage rating is 1500 Vrms. - What is the signal bandwidth of the ISO122U?
The signal bandwidth is 50 kHz. - What is the operating temperature range of the ISO122U?
The operating temperature range is from -25°C to 85°C. - What is the storage temperature range of the ISO122U?
The storage temperature range is from -40°C to 125°C. - How does the ISO122U achieve galvanic isolation?
The ISO122U achieves galvanic isolation through digital modulation of the input signal across a high-voltage differential capacitive barrier. - What is the quiescent current of the ISO122U?
The quiescent current is ±5 mA on VS1 and ±5.5 mA on VS2. - What are some common applications of the ISO122U?
Common applications include industrial process control, ground loop elimination, motor and SCR control, power monitoring, PC-based data acquisition, and test equipment. - Is the ISO122U still recommended for new designs?
No, the ISO122U is not recommended for new designs as it has been announced for discontinuation by Texas Instruments.
