The provided text describes the EL817 series, an electronic component that combines an infrared emitting diode with a phototransistor detector, along with its characteristics as a micropower instrumentation amplifier.1 The description highlights its packaging, electrical specifications, and typical applications.
Dual Functionality and Packaging
The EL817 series devices are presented as versatile components, primarily consisting of an
infrared emitting diode optically coupled to a phototransistor detector.2 This optical isolation capability is fundamental to its design. It is available in a standard
4-pin DIP package, with options for wide-lead spacing and surface-mount device (SMD) configurations, catering to different design and manufacturing needs.3
Micropower Instrumentation Amplifier Features
Beyond its optical coupling, the EL817 is specifically designed as a
micropower instrumentation amplifier. It is optimized for
single-supply operation, accommodating a voltage range from +2.4V to +5.5V, making it suitable for low-power applications. A notable feature is its
rail-to-rail input and output operation, which maximizes dynamic range in single-supply environments.4 The amplifier is highly efficient, consuming only
65µA typical supply current, which is crucial for power-sensitive designs.
As an instrumentation amplifier, the EL817 boasts
very high common-mode rejection due to its pair of independent inputs. Its feedback terminals offer flexibility, allowing the translation of a zero input to any output offset, including ground.5 The overall gain of the amplifier is controlled by a feedback divider.6 The EL817 is compensated for gains of 100 or more and features
bipolar input devices to achieve optimal offset and 1/f noise performance.7 Its ability to operate from a single lithium cell or two Ni-Cd batteries further underscores its low-power credentials.
The input range of the EL817 extends from ground to slightly above the positive rail, and its output stage can swing to both ground and the positive supply, eliminating the need for external pull-up or pull-down resistors.8
Key Applications
The article lists several typical applications where the EL817's characteristics are particularly beneficial:
- Battery- or solar-powered systems: Due to its micropower consumption and ability to operate from low voltage sources.
- Strain gauge current monitors: Leveraging its precision and common-mode rejection for accurate measurements.
- Thermocouple amplifiers: Utilizing its low noise and ability to amplify small differential signals.
In summary, the EL817 series is presented as a highly efficient and versatile component, serving both as an optocoupler and a low-power instrumentation amplifier, making it suitable for a range of sensitive measurement and power-constrained applications.
There is no need for a tool code block as all the necessary information has been extracted from the user's provided text.This informative text describes the EL817 series of devices, highlighting their dual nature as both infrared optocouplers and micropower instrumentation amplifiers. The explanation covers their technical specifications, operational characteristics, and common applications.
Optocoupler and Packaging Details
The EL817 series is introduced as a device comprising an
infrared emitting diode optically coupled to a phototransistor detector.9 This optical isolation characteristic is a core feature. The devices are housed in a
4-pin DIP package, with additional options for wide-lead spacing and Surface Mount Device (SMD) configurations, providing flexibility for various design and manufacturing needs.10
Micropower Instrumentation Amplifier Capabilities
Beyond its optocoupler function, the EL817 is detailed as a
micropower instrumentation amplifier specifically optimized for
single-supply operation, ranging from +2.4V to +5.5V.11 A significant advantage is its
rail-to-rail input and output operation, which maximizes signal range even with low supply voltages.12 The amplifier is highly power-efficient, consuming only
65µA typical supply current, making it ideal for battery-powered or energy-harvesting systems.
As an instrumentation amplifier, it offers
very high common-mode rejection, thanks to its independent input pair.13 The flexible feedback terminals allow for output offset adjustments, including translation of zero input to ground.14 The overall gain is controlled by a feedback divider, and the EL817 is compensated for gains of 100 or more.15 The inclusion of
bipolar input devices contributes to excellent offset and 1/f noise performance.16 The device can be powered by a single lithium cell or two Ni-Cd batteries, and its input range extends from ground to slightly above the positive rail, with an output stage that swings to both ground and the positive supply, eliminating the need for external pull-up or pull-down resistors.17
Key Applications
The versatility of the EL817 is further highlighted by its suggested applications:
- Battery- or solar-powered systems: Directly benefiting from its low power consumption and flexible power supply requirements.
- Strain gauge current monitors: Leveraging its high precision and common-mode rejection for accurate sensing.
- Thermocouple amplifiers: Utilizing its ability to amplify very small differential voltages from thermocouples with low noise.
In essence, the EL817 series is presented as a robust and energy-efficient component suitable for precise measurement and isolation applications in power-sensitive environments.
