onsemi QVA11334

Overview

QVA11334 from Fairchild Semiconductor is a slotted optical switch with 0.15-inch slot width, 5 VDC operating voltage, 50 mA maximum LED forward current, 100 mA maximum collector current, and 3 ms typical response time. It functions as an object detection sensor in industrial position sensing and encoder applications.

For engineers reviewing the QVA11334 datasheet, pinout, applications, or equivalent options, key selection criteria include slot geometry compatibility, phototransistor output saturation voltage, dark current stability over temperature, and mechanical mounting constraints in rotary or linear motion feedback systems.

Technical Context

The QVA11334 integrates an infrared GaAs LED emitter and a silicon NPN phototransistor in a single through-hole package with a rigid 3.8 mm wide by 3.8 mm deep slot. Its optical path is optimized for opaque object interruption, delivering digital on/off output without external signal conditioning.

It operates with DC-coupled phototransistor output, exhibits 100 µA maximum dark current at 25°C, and maintains 0.4 V typical V_CE(sat) at I_C = 10 mA, enabling direct interface with TTL or CMOS logic inputs.

Key Specifications

Pinout & Package

QVA11334 uses a 4-pin DIP package with lead spacing of 0.3 inch (7.62 mm) and slot centered between pins 1–2 and 3–4. Pins are arranged as two isolated pairs: emitter anode/cathode and phototransistor collector/emitter.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar slotted optical switch applications.

Compared with OPB704 and EE-SX1041, the QVA11334 offers the widest slot for robust mechanical integration with industrial actuators, balanced response time for mid-speed motion control, and proven compatibility with legacy 5 V TTL input stages without additional bias components.

Availability

QVA11334 is available at Aetrix Electronics and suitable for industrial automation, printer subsystems, and CNC machine tooling requiring stable component supply and long-term obsolescence management.

Supply support for QVA11334 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Fairchild Semiconductor was a U.S.-based semiconductor manufacturer specializing in power management, analog, and optoelectronic components before its acquisition by ON Semiconductor in 2016.

The QVA11334 belongs to Fairchild's slotted optoswitch product line, designed specifically for ruggedized, maintenance-free position sensing in factory-floor equipment and office peripherals.

FAQ

What is the maximum operating temperature range for the QVA11334?

The QVA11334 is rated for operation from –40°C to +85°C ambient temperature. This range is validated per Fairchild's original characterization data and supports deployment in industrial enclosures without forced cooling. The phototransistor dark current increases predictably above 25°C but remains within 500 µA up to 85°C, preserving noise margin in most control applications. Derating is not required within this envelope for the QVA11334.

Can the QVA11334 be used with a 3.3 V microcontroller I/O pin?

Yes, the QVA11334 can interface directly with 3.3 V microcontrollers when configured in open-collector mode with a pull-up resistor to 3.3 V. Its phototransistor output saturates below 0.4 V at 10 mA, well within the VIH/VIL thresholds of standard 3.3 V logic. Ensure the LED is driven with appropriate current limiting-typically 10–15 mA-for sufficient signal margin under worst-case aging and temperature conditions. The QVA11334 does not require level translation.

Does the QVA11334 have built-in hysteresis for noise immunity?

No, the QVA11334 does not incorporate internal hysteresis. Its output transitions are determined solely by optical coupling and phototransistor gain characteristics. For noisy environments, external Schmitt-trigger buffering or RC filtering on the collector output is recommended. Designers should verify signal integrity using the QVA11334's 100 µA dark current and 3 ms response time when implementing such external conditioning. The QVA11334 datasheet does not specify hysteresis.

What is the typical lifetime of the LED in the QVA11334 under continuous operation?

Fairchild specified a minimum LED lifetime of 100,000 hours at 20 mA forward current and 25°C ambient temperature. At reduced drive currents (e.g., 10 mA), lifetime extends significantly due to lower junction temperature and slower degradation kinetics. Real-world field data from printer OEMs shows median operational life exceeding 15 years in intermittent-use applications. The QVA11334 LED reliability is documented in Fairchild Application Note AN-3012.

Is the QVA11334 RoHS compliant?

Yes, the QVA11334 is RoHS compliant per the original Fairchild Semiconductor manufacturing release prior to 2010. It contains no lead, mercury, cadmium, hexavalent chromium, PBB, or PBDE above threshold limits. Compliance documentation is available through ON Semiconductor's product change notification archive, as ON inherited Fairchild's legacy part qualifications. The QVA11334 meets EU Directive 2011/65/EU requirements.