1458 Optocoupler Datasheet

The HCPL-1458 (often referred to simply as the 1458 optocoupler) is a high-speed, hermetically sealed logic gate optocoupler primarily manufactured by Broadcom (formerly Avago). It is specifically engineered for high-reliability applications, including industrial, aerospace, and medical systems where signal integrity and electrical isolation are critical. Key Specifications and Performance

The HCPL-1458 is known for its high-speed performance and robust isolation capabilities. Below are the typical parameters found in its datasheet:

Propagation Delay: Typically 8 ns to 35 ns (depending on specific testing conditions and sub-variants like the HCPL-1458#060), allowing for high-frequency signal transmission.

Isolation Voltage: Provides a high insulation voltage of 5000 Vrms (or 3750 Vrms for certain packages like the standard 8-pin DIP).

Common Mode Rejection (CMR): Minimum of 15,000 V/μs at 1500 V peak, ensuring the device remains immune to high-voltage transients. Supply Voltage ( VCCcap V sub cap C cap C end-sub

): Operates within a range of 3.0V to 5.5V, making it compatible with standard TTL and CMOS logic levels.

Output Type: Open-collector output, which can handle voltages up to 20V. Pin Configuration (8-Pin DIP/SO-8)

The HCPL-1458 generally follows the standard high-speed optocoupler pinout: Description 1 No internal connection 2 Input LED anode 3 Input LED cathode 4 No internal connection 5 6 VOcap V sub cap O Output voltage (Open collector) 7 No internal connection (or sometimes VEcap V sub cap E 8 VCCcap V sub cap C cap C end-sub Positive supply voltage Typical Applications

Because of its hermetic sealing and high-speed operation, the 1458 is frequently used in:

Digital Logic Isolation: Protecting microcontrollers from high-voltage transients in industrial environments.

High-Speed Communication: Isolating line receivers and data transmission systems like RS-485 or CAN bus.

Power Supply Feedback: Providing isolated feedback in switching power supplies.

Medical Equipment: Ensuring patient safety through high-voltage galvanic isolation. Important Distinction: HCPL-1458 vs. MC1458 Single Channel, High Speed Optocouplers Technical Data

The HCPL-1458 (also referred to as the A1458) is a high-speed, logic-gate optocoupler primarily manufactured by Broadcom (formerly Avago/Agilent). It is designed to provide high-speed signal isolation between a circuit's input and output, protecting sensitive low-voltage components from high-voltage transients. Key Technical Specifications

The HCPL-1458 is characterized by its high common-mode rejection and speed, making it suitable for demanding industrial environments. Typical Value Description Data Rate Maximum signal transmission speed Propagation Delay 4 µs (typical) Signal delay time from input to output Isolation Voltage 3750 Vrms to 5300 Vrms Maximum rated isolation Operating Voltage (Vcc) 4.5 V to 5.5 V Standard logic-level supply voltage Operating Temperature -40°C to +85°C Range for industrial applications Current Transfer Ratio 60% (minimum) Ratio of output current to input current Pinout Configuration

The HCPL-1458 is typically housed in an SOP-8 or DIP-8 package. While specific internal diagrams vary by variant, a standard high-speed 8-pin optocoupler often follows this general layout:

Pin 1 & 4: Usually NC (No Connection) or specific anode/cathode pins. Pin 2: Anode (Input LED). Pin 3: Cathode (Input LED). Pin 5: GND (Output side). Pin 6: Vout (Output Signal). Pin 7: NC or Enable. Pin 8: Vcc (Supply Voltage). Common Applications

Industrial Control Systems: Maintaining electrical isolation between microcontrollers and high-power industrial equipment.

Switch-Mode Power Supplies (SMPS): Used in feedback loops to safely transmit regulation signals across isolation barriers.

Motor Drive Circuits: Protecting low-voltage control systems from the high voltages used in AC or DC motor drives.

Renewable Energy: Isolation in solar inverters and wind turbine controllers. Important Note on the "1458" Part Number

In the electronics industry, "1458" is also a very common designation for the MC1458 or LM1458. However, these are Dual Operational Amplifiers, not optocouplers. If your component is an 8-pin IC used for signal amplification rather than isolation, you are likely looking for the MC1458 Datasheet. MC1458 - STMicroelectronics

The 1458 designation typically refers to several distinct electronic components depending on the manufacturer prefix. In the context of optocouplers, it most commonly refers to the HCPL-1458 (a high-performance, hermetically sealed isolator) or the A1458 series.

Note: If you are looking for the common MC1458, that is a dual operational amplifier, not an optocoupler. HCPL-1458 / HCPL-A1458 Technical Overview

The HCPL-1458 is a high-speed, high-gain optocoupler manufactured by Broadcom (formerly Avago/Agilent). It is designed for applications requiring high reliability in harsh environments, often featuring a hermetically sealed SOP-8 package. Key Features & Specifications

High-Speed Operation: Features a propagation delay of approximately 35 ns at 10 kHz, making it suitable for fast signal transmission. Wide Supply Range: Operates with a VCCcap V sub cap C cap C end-sub

range of 3.0V to 5.5V, allowing compatibility with both legacy 5V and modern 3.3V logic systems.

High Gain: Designed for applications where signal amplification and isolation are needed simultaneously.

Isolation Voltage: Typically provides high isolation levels (often cited up to 5300 Vrms for related series like HCPL-A1458) to protect sensitive logic from high-voltage transients.

Low Power Consumption: Designed for efficient operation with a typical ICCcap I sub cap C cap C end-sub around 1.2 mA. Core Applications

The HCPL-1458 series is frequently used in industrial and high-reliability sectors:

Industrial Control Systems: Ground loop elimination and signal isolation in noisy factory environments.

Motor Drives: Isolating power transistors and feedback elements.

Data Communications: High-speed logic ground isolation (TTL/CMOS compatible).

Military & Aerospace: Due to its hermetically sealed package, it is often selected for environments where moisture or contaminants would degrade standard plastic packages. Distinguishing the 1458 Family

Because "1458" is a popular part number, it is critical to verify the specific device type: MC1458 - STMicroelectronics

is a high-performance, high-speed optocoupler designed to provide reliable electrical isolation for high-frequency signal transmission. It is frequently used in industrial and power electronics to protect sensitive low-voltage components, like microcontrollers, from high-voltage spikes and noise. Key Technical Specifications 1458 optocoupler datasheet

is optimized for speed and stability across a wide range of operating conditions Operating Voltage ( cap V sub cap C cap C end-sub

3.0V to 5.5V, offering flexibility for both 3.3V and 5V logic systems. Propagation Delay:

35 ns (typical) at 10 kHz, making it suitable for high-data-rate communication. Output Type:

TTL-compatible open-collector output, allowing for direct interfacing with various logic families. Package Type: Typically available in a hermetically sealed

or 8-pin widebody package, ensuring long-term reliability in harsh environments. Isolation:

Designed for high-voltage galvanic isolation barriers to prevent ground loops. Core Functionality Like most optocouplers, the consists of two primary internal components: Input Side:

An infrared LED that converts an electrical signal into light. Output Side:

A photosensitive integrated photodetector (often a phototransistor or logic gate) that detects the light and converts it back into an electrical signal.

This light-based transmission path ensures that there is no direct electrical connection between the input and output, protecting the control circuitry from electromagnetic interference (EMI) and power surges. LTC1458/LTC1458L - Analog Devices

Daisy-Chained Control Outputs. The LTC®1458/LTC1458L are complete single supply, quad rail-to-rail voltage output, 12-bit digital- Analog Devices Single Channel, High Speed Optocouplers Technical Data

(often referred to simply as the 1458 optocoupler) is a high-performance, hermetically sealed high-speed optocoupler

manufactured by Broadcom (formerly Avago/Agilent). It is designed specifically for applications requiring reliable signal isolation in harsh environments, such as industrial control and medical equipment. 1. Key Specifications & Performance High-Speed Operation:

Features a propagation delay of approximately 35 ns, making it suitable for fast digital logic. Wide Supply Voltage ( cap V sub cap C cap C end-sub Operates across a range of 3.0V to 5.5V

, allowing flexibility for both legacy 5V systems and modern 3.3V logic. Low Input Drive: Designed with a "Low cap I sub cap F

" feature, meaning it requires minimal current from a microcontroller's GPIO to trigger. Common Mode Rejection (CMR):

Provides high transient immunity (up to 50 kV/μs), which protects signals from high-frequency noise. Hermetic Sealing: Packaged in a hermetically sealed SOP-8

to protect internal components from moisture and environmental contaminants. 2. Pin Configuration (SOP-8) While you should always verify with a specific manufacturer's PDF

, high-speed logic gate optocouplers like the 1458 typically follow this standard 8-pin layout: Input Side: Pins for the Anode and Cathode of the internal GaAsP LED. Output Side: cap V sub cap C cap C end-sub , Ground, and the Open Collector output. 3. Essential Design Considerations

When integrating the 1458 into your circuit, pay close attention to these parameters found in the Vishay datasheet guidelines Current Transfer Ratio (CTR): Even for high-speed logic gates, ensure the input current ( cap I sub cap F ) is sufficient to drive the output stage. Open Collector Output: This device often requires an external pull-up resistor

on the output pin to interface correctly with digital logic. Isolation Voltage ( cap V sub i s o end-sub Rated for up to cap V sub r m s end-sub

, ensuring safety between high-voltage power stages and low-voltage control circuits. 4. Typical Applications Isolated Data Acquisition:

Protecting sensitive measurement systems from noisy ground loops. Motor Control:

Providing feedback loops for motor drives while isolating high-voltage power stages. Inverter Circuits:

Used in renewable energy systems like solar or wind inverters. Ovaga Technologies or a list of equivalent components if the 1458 is unavailable in your region?

Understanding the 1458 Optocoupler Datasheet: A Comprehensive Guide

The 1458 optocoupler is a type of optoelectronic device that combines a light-emitting diode (LED) and a phototransistor to provide electrical isolation between two circuits. This device is commonly used in applications where high voltage insulation is required, such as in power supplies, motor control circuits, and industrial automation systems. In this article, we will provide an in-depth analysis of the 1458 optocoupler datasheet, covering its features, specifications, and applications.

Overview of the 1458 Optocoupler

The 1458 optocoupler is a dual-channel device that consists of two independent optocouplers in a single package. Each channel consists of an infrared LED and a phototransistor, which are optically coupled to provide electrical isolation between the input and output circuits. The device is available in a variety of packages, including DIP-8, SMD-8, and SOP-8.

Key Features of the 1458 Optocoupler

The 1458 optocoupler datasheet highlights several key features that make this device suitable for a wide range of applications. Some of the key features include:

• High voltage insulation: The 1458 optocoupler provides a high level of electrical isolation between the input and output circuits, with a withstand voltage of up to 5000V RMS.
• High current transfer ratio: The device has a high current transfer ratio (CTR) of up to 600%, which ensures efficient signal transfer between the input and output circuits.
• Low input current: The 1458 optocoupler requires a low input current of 1mA to 10mA, making it suitable for use in low-power applications.
• High-speed operation: The device has a fast response time of up to 10μs, making it suitable for high-speed applications.

Specifications of the 1458 Optocoupler

The 1458 optocoupler datasheet provides a detailed list of specifications that define the device's performance and characteristics. Some of the key specifications include:

• Absolute maximum ratings:
  • Input voltage: 30V
  • Output voltage: 30V
  • Input current: 20mA
  • Output current: 50mA
  • Power dissipation: 100mW
• Electrical characteristics:
  • CTR: 50% to 600%
  • Input current: 1mA to 10mA
  • Output current: 1mA to 50mA
  • Response time: 10μs to 50μs
• Optical characteristics:
  • Wavelength: 940nm
  • Spectral sensitivity: 400 to 1100nm

Applications of the 1458 Optocoupler

The 1458 optocoupler is widely used in a variety of applications where high voltage insulation and efficient signal transfer are required. Some of the common applications include:

• Power supplies: The 1458 optocoupler is used in power supplies to provide electrical isolation between the primary and secondary circuits.
• Motor control circuits: The device is used in motor control circuits to provide isolation between the control circuit and the motor.
• Industrial automation systems: The 1458 optocoupler is used in industrial automation systems to provide isolation between the control circuit and the actuator.
• Medical equipment: The device is used in medical equipment to provide isolation between the patient and the equipment.

How to Use the 1458 Optocoupler Datasheet

The 1458 optocoupler datasheet provides a wealth of information that can be used to design and develop applications that utilize this device. Here are some tips on how to use the datasheet: The HCPL-1458 (often referred to simply as the

• Understand the device's limitations: The datasheet provides information on the device's absolute maximum ratings, which define the limits of the device's performance.
• Select the right package: The datasheet provides information on the different packages available, which can affect the device's performance and compatibility with other components.
• Design for high voltage insulation: The datasheet provides information on the device's high voltage insulation capabilities, which can be used to design applications that require high voltage insulation.

Conclusion

The 1458 optocoupler datasheet provides a comprehensive overview of the device's features, specifications, and applications. By understanding the device's performance and characteristics, designers and engineers can develop applications that utilize the 1458 optocoupler to provide high voltage insulation and efficient signal transfer. Whether you're designing a power supply, motor control circuit, or industrial automation system, the 1458 optocoupler datasheet is an essential resource that can help you get the job done.

References

• 1458 Optocoupler Datasheet: [Insert datasheet link or attachment]
• Optocoupler Applications: [Insert application notes or reference designs]
• Design Considerations: [Insert design considerations or guidelines]

Appendix

The following appendix provides additional information on the 1458 optocoupler datasheet:

• Package Dimensions: [Insert package dimensions]
• Pin Configuration: [Insert pin configuration]
• Schematic Diagrams: [Insert schematic diagrams]

By providing a comprehensive overview of the 1458 optocoupler datasheet, this article aims to help designers and engineers understand the device's features, specifications, and applications, and to provide a valuable resource for designing and developing applications that utilize this device.

is most famously associated with the classic MC1458 / LM1458 Dual Operational Amplifier

. However, if you are strictly looking for an optocoupler, you are likely referring to the high-speed

(often colloquially called the A1458) manufactured by Avago (now Broadcom). STMicroelectronics

Because datasheets vary wildly based on the exact component you have in hand, official documentation and highly-rated repositories for both options are listed below. 1. High-Speed Optocoupler (HCPL-1458 / A1458)

If your part is an 8-pin SOIC or DIP high-speed logic gate optocoupler, this is the component you need. Manufacturer: Avago Technologies / Broadcom Key Features:

High-speed propagation, low power consumption, and high common-mode transient immunity (CMR). Datasheet Archive:

You can view technical parameters and search for the exact PDF on the ALLDATASHEET HCPL-1458 Search Page 2. Dual Operational Amplifier (MC1458 / LM1458)

If your part is a classic 8-pin analog amplifier (not an optical isolator), it is a dual op-amp derived from the industry-standard mu cap A 741 STMicroelectronics MC1458 - STMicroelectronics

The HCPL-1458 (also known as the A1458) is a high-speed, hermetically sealed logic gate optocoupler originally manufactured by Avago Technologies (now Broadcom). It is primarily used for electrical isolation in high-reliability and industrial applications. Key Features

High-Speed Performance: Supports data rates with a maximum propagation delay ( ) of 8 ns. Wide Power Supply Range: Operates on a VCCcap V sub cap C cap C end-sub

range of 3.0V to 5.5V, allowing flexibility for different logic levels.

High Noise Immunity: Provides high common-mode transient immunity (CMR) of at least 50 kV/µs.

Superior Isolation: Rated for an isolation voltage of 5300 Vrms. Low Power Consumption: Maximum supply current ( ICCcap I sub cap C cap C end-sub

) is approximately 1.2 mA, making it suitable for power-sensitive designs.

Hermetic Packaging: Available in an 8-pin hermetically sealed package (SOP-8 or similar), protecting internal components from environmental factors. Electrical Specifications Typical/Max Value Forward Current ( IFcap I sub cap F ) 20 mA (Max) Output Current ( ICcap I sub cap C ) Operating Temperature -55°C to +100°C Propagation Delay 35 ns at 10 kHz Common Applications

Industrial Control Systems: Protecting microcontrollers from high-voltage spikes and ground loops.

Telecommunications: High-speed digital signal switching and line receivers.

Medical Equipment: Ensuring electrical isolation for patient safety in diagnostic devices.

Power Supplies: Used as a feedback element in switched-mode power supplies (SMPS). Comparison Note

Be careful not to confuse the HCPL-1458 with the LM1458 or MC1458. While they share the "1458" number, the LM1458 is a Dual Operational Amplifier and does not provide optical isolation.

If you are looking for specific pinout diagrams or price availability from distributors like Broadcom or Utsource, let me know. LM1458/LM1558 Dual Operational Amplifier datasheet (Rev. D)

, which is not an optocoupler. However, if you are looking for an optocoupler with a similar designation, the Go to product viewer dialog for this item.

is a high-performance component manufactured by Avago Technologies (now Broadcom). HCPL-1458 High-Gain Optocoupler The

is a hermetically sealed, high-gain optocoupler designed for reliable signal isolation. It combines a GaAsP LED with an integrated high-gain photodetector to provide electrical insulation between input and output circuits. Key Specifications & Features

High Performance: Optimized for high-speed and low-voltage operations. Voltage Supply ( VCCcap V sub cap C cap C end-sub

): Features a wide supply range, allowing for flexibility in various system designs. Power Consumption: Low input current ( IFcap I sub cap F ) requirements help reduce total drive power needs.

Isolation: Provides high isolation voltage, typically around 5300 Vrms, and high common-mode transient immunity (CMR) of 50 kV/µs.

Packaging: Commonly available in a compact SOP-8 or SOIC package style. Pin Configuration (Standard SOP-8) While pinouts can vary by manufacturer, the typically follows this configuration: Input Pins: Dedicated to the LED power supply and ground.

Output Pins: Connect to the high-gain photodetector for signal retrieval and isolation. Applications The

is frequently used in environments where noise sensitivity is high and reliable isolation is critical: High voltage insulation : The 1458 optocoupler provides

Industrial Control Systems: Used for signal switching and motor control.

Power Supplies: Found in switching power supplies and DC-DC converters.

Communications: Applied in data communication systems and automotive electronics. Note on Potential Confusion If your project involves the MC1458 Dual Op-Amp Go to product viewer dialog for this item.

, note that it is an analog component with two μA741-style amplifiers

in one package. Some modern digital-to-analog converters, like the Go to product viewer dialog for this item.

, are designed with clock inputs that allow for a direct optocoupler interface for better isolation.

with other high-speed optocouplers, or were you specifically looking for the MC1458 Op-Amp Go to product viewer dialog for this item. details? LTC1458 Datasheet and Product Info - Analog Devices

) is a high-performance, hermetically sealed optocoupler designed for high-speed digital isolation in demanding environments. Type: High-speed logic gate optocoupler. Key Specs: Speed: Typically 10 MBd (megabaud).

Isolation Voltage: Standard models offer around 1500V to 5300Vrms isolation.

Common Mode Rejection (CMR): High immunity to noise transients (often >50 kV/µs). Supply Voltage: Wide range, often 3.0V to 5.5V.

Packaging: Commonly found in DIP-8, DIP-16, or SOP-8 packages, sometimes with hermetic sealing for military or aerospace use.

Datasheet: You can find technical specifications on distributor sites like Alldatasheet or the manufacturer’s product page. 2. Other Components with "1458"

Because "1458" is a very common part number, ensure you aren't actually looking for one of these: MC1458 Dual Op-Amp Go to product viewer dialog for this item.

: One of the most famous chips with this number. It is a dual version of the classic 741 operational amplifier, used for general-purpose analog signal processing. LTC1458 12-Bit DAC

: A quad 12-bit digital-to-analog converter from Analog Devices. Its datasheet mentions an "optocoupler interface," which might be why it appeared in your search. Quick Verification Checklist: Does your part have 8 or 16 pins? (Likely the HCPL-1458 optocoupler Is it used for analog signal gain in a circuit? (Likely the MC1458 op-amp Is it in a larger SO-28 package? (Likely the LTC1458 DAC

Which of these specific 1458 components are you building into your project? AI responses may include mistakes. Learn more MC1458 - STMicroelectronics

Report: 1458 Optocoupler Datasheet Analysis

Introduction

The 1458 optocoupler, also known as the PC817 or 817 optocoupler, is a popular optoelectronic device used for electrical isolation and signal transfer between two circuits. This report provides an in-depth analysis of the 1458 optocoupler datasheet, highlighting its key features, specifications, and applications.

Overview

The 1458 optocoupler is a dual-channel device that consists of two LEDs and two phototransistors, packaged in a 8-pin DIP (Dual In-line Package) or SOP (Small Outline Package). Its primary function is to transfer signals between two electrically isolated circuits while providing protection against high voltage spikes, noise, and other forms of electrical interference.

Key Features

1. High Isolation Voltage: The 1458 optocoupler offers a high isolation voltage of up to 5000V RMS, making it suitable for applications requiring high voltage insulation.
2. High Current Transfer Ratio: The device has a high current transfer ratio (CTR) of 50% to 600%, ensuring efficient signal transfer between the input and output circuits.
3. Low Input Current: The 1458 optocoupler requires a low input current of 1mA to 10mA, making it suitable for low-power applications.
4. High Speed: The device has a fast response time, with a typical rise and fall time of 4µs and 5µs, respectively.

Specifications

Electrical Characteristics

• Input
  • Forward voltage: 1.2V to 1.4V
  • Reverse voltage: 6V
  • Input current: 1mA to 10mA
• Output
  • Collector-emitter voltage: 30V
  • Emitter-collector voltage: 5V
  • Output current: 50mA
• Isolation
  • Isolation voltage: 5000V RMS
  • Isolation resistance: 10^12 Ω

Optical Characteristics

• Current Transfer Ratio (CTR): 50% to 600%
• Response Time
  • Rise time: 4µs
  • Fall time: 5µs

Absolute Maximum Ratings

• Storage Temperature: -40°C to 125°C
• Operating Temperature: -30°C to 100°C
• Lead Soldering Temperature: 260°C

Applications

The 1458 optocoupler is widely used in various applications requiring electrical isolation and signal transfer, including:

1. Power Supplies: Feedback control, isolation, and protection
2. Industrial Control Systems: Motor control, process control, and data acquisition
3. Medical Equipment: Patient monitoring, diagnostic equipment, and medical imaging
4. Communication Systems: Data transmission, signal isolation, and noise reduction
5. Automotive Systems: Battery management, motor control, and lighting control

Conclusion

The 1458 optocoupler is a reliable and versatile device that offers high isolation voltage, high current transfer ratio, and fast response time. Its wide range of applications and compatibility with various packages make it a popular choice among designers and engineers. By analyzing the datasheet, we have highlighted the key features, specifications, and applications of the 1458 optocoupler, providing valuable insights for users and designers.

Pinout (common transistor-output optocoupler, DIP-4)

• Pin 1: Anode (LED)
• Pin 2: Cathode (LED)
• Pin 3: Emitter (phototransistor)
• Pin 4: Collector (phototransistor)

Part 4: How to Read the Graphs – Beyond the Numbers

A true datasheet wizard reads the graphs, not just the tables. For your 1458-style optocoupler, focus on these three graphs:

1. IF vs. VF (LED Current vs. Voltage): This helps you calculate the exact current-limiting resistor. If your VCC is 5V, and VF is 1.3V at 10mA, the resistor is (5-1.3)/0.01 = 370 ohms (use 330 or 390 standard).
2. Normalized CTR vs. IF: This shows that running the LED at 1mA might give only 30% of the rated CTR. For reliable switching, run the LED between 5mA and 20mA.
3. CTR vs. Ambient Temperature: At -25°C, CTR might be 80% of nominal. At 85°C, it could drop to 50%. Always derate your design for the highest temperature your product will see.

Reliability & Compliance

• IEC 60747‑5‑1 (Optoelectronic devices)
• RoHS compliant – lead‑free, halogen‑free.
• MTBF: > 100 000 h at 85 °C, 50 % duty cycle.

3.1 General Description

The PC1458 is an optically coupled isolator consisting of a Gallium Arsenide (GaAs) infrared emitting diode (IRED) optically coupled to a silicon phototransistor detector. It is housed in a standard 4-pin DIP (Dual In-line Package).

10. Application Circuit Example

Microcontroller to 24V PLC Input Isolation:

• Input side: Connect microcontroller pin → 330Ω resistor → Pin 1 (Anode). Pin 2 (Cathode) → GND.
• Output side: Pin 5 (Collector) → ( V_CC ) = 24V via 10kΩ pull-up → also to PLC input. Pin 4 (Emitter) → GND.
• No external base connection (Pin 6 open).

Conclusion

The 1458 optocoupler is a robust component essential for noise reduction and safety in circuit design. By understanding the datasheet parameters—specifically Forward Voltage, CTR, and Isolation Voltage—you can safely implement it in your designs to bridge the gap between low-power logic and high-power peripherals.

Just remember to double-check that you haven't accidentally picked up a 1458 Op-Amp!

Have you used this component in a project? Are you having trouble identifying a specific marking? Drop a comment below with a photo or description!

Typical Use Cases

• Microcontroller I/O isolation – protects low‑voltage logic from high‑voltage transients.
• Switch‑mode power supply feedback – isolates control loop from noisy power stage.
• Serial communication (UART/RS‑232) isolation – prevents ground loops.

1. Features and Package

The first page tells you the physical format. Look for:

• Package Type: DIP-6 (6-pin dual inline package) or DIP-8. The 4N35 uses DIP-6.
• Isolation Voltage: This is the key spec. Typically, V_ISO (RMS) is 2.5kV to 5kV. For a 1458-equivalent, expect >2500Vrms.
• Current Transfer Ratio (CTR): The gain of an optocoupler. The 4N35 has a minimum CTR of 100% at 10mA. This means if you put 10mA into the LED, you get at least 10mA out of the transistor.