AD694AQ
4-20mA current transmitter ICs in 16-pin CDIP packages
Manufacturer： ['rochester', 'analog-devices']
series introduction
# AD694AQ Product Series Introduction
## 1. Overview
The AD694AQ is a high - performance, precision current - output transducer integrated circuit that belongs to Analog Devices' extensive portfolio of signal conditioning and conversion products. This product series is specifically designed to meet the demanding requirements of industrial and instrumentation applications where accurate and reliable current transmission is crucial.
## 2. Key Features
### 2.1 High Precision
- The AD694AQ offers excellent accuracy in converting input voltage signals to output current signals. It has a low offset error and gain error, which ensures that the output current accurately represents the input voltage. This high precision is essential in applications such as process control, where even small errors can lead to significant deviations in the controlled process.
- The device also features a high linearity, typically better than 0.01%, which means that the relationship between the input voltage and the output current is highly linear over a wide range of input values. This linearity is crucial for maintaining the integrity of the signal being transmitted.
### 2.2 Wide Input and Output Ranges
- **Input Voltage Range**: It can accept a wide range of input voltages, usually from 0 - 10V. This flexibility allows it to interface with a variety of sensors and signal sources that produce voltage outputs within this range.
- **Output Current Range**: The AD694AQ is capable of providing an output current in the standard industrial range of 4 - 20mA. This 4 - 20mA current loop is widely used in industrial applications because it is immune to electrical noise and can be transmitted over long distances without significant signal degradation.
### 2.3 Low Power Consumption
In today's energy - conscious world, the AD694AQ is designed to consume minimal power. This low power consumption not only reduces the overall energy requirements of the system but also helps in minimizing heat generation, which can be beneficial for the long - term reliability of the device and the surrounding components.
### 2.4 Robustness and Reliability
- The AD694AQ is built with high - quality semiconductor materials and advanced manufacturing processes, which make it highly resistant to environmental factors such as temperature variations, humidity, and electrical noise.
- It also has built - in protection features such as short - circuit protection and over - voltage protection. These features safeguard the device from damage due to abnormal operating conditions, ensuring its long - term reliability in harsh industrial environments.
## 3. Functional Block Diagram and Working Principle
### 3.1 Block Diagram
The AD694AQ consists of several key functional blocks, including an input amplifier, a voltage - to - current converter, and an output current driver. The input amplifier is responsible for buffering and amplifying the input voltage signal to a suitable level for further processing. The voltage - to - current converter then converts the amplified voltage signal into a proportional current signal. Finally, the output current driver provides the necessary power to drive the output current through the load.
### 3.2 Working Principle
When an input voltage is applied to the AD694AQ, the input amplifier first amplifies the signal. The amplified voltage is then fed into the voltage - to - current converter, which uses a precision resistor network to convert the voltage into a current. The output current is then regulated and driven through the load, which can be a long - distance transmission line or a receiving device such as a controller or a display.
## 4. Applications
### 4.1 Industrial Process Control
In industrial process control systems, the AD694AQ is used to convert the output signals of sensors such as temperature sensors, pressure sensors, and flow sensors into 4 - 20mA current signals. These current signals can then be transmitted over long distances to a central control room, where
Images for reference
16-CDIP Pkg
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