LM393QT

LM393QT is a dual, low-power voltage comparator in the LM393 family. It contains two independent comparators with open-collector outputs, allowing simple wired-OR connections and easy level shifting. How it works: when the non-inverting input exceeds the inverting input, the corresponding output sinks current; otherwise an external pull-up resistor pulls the output high. Key specs (typical): supply 2–36 V; low quiescent current (a few hundred µA per comparator); input common-mode includes ground but typically goes only up to about Vcc − 1.5 V; each output can sink up to ~16 mA. No built-in hysteresis; add positive feedback if you need noise immunity. Applications: simple threshold detectors, zero-cross detectors, battery/level sensing, and other basic comparator tasks. The QT suffix mainly indicates packaging/grade for a vendor; electrically it behaves like a standard LM393 dual comparator. Remember to use proper pull-ups and respect input/output voltage ranges for reliable operation.

LM393QT is TI’s dual, open-collector comparator. Direct cross-refs include:
- LM393 (same device, TI) and LM393N (older/legacy)
- LM2903 (dual comparator, open-collector; pin-compatible in many packages)
- KA393 / KA393A (ROHM)
Note: exact pinouts and voltage ranges vary by vendor and package; verify datasheets for drop-in compatibility before substitution.

LM393QT features (dual comparator, open-collector)
- Dual, general-purpose voltage comparators
- Open-collector outputs (sink current only; requires pull-up resistors)
- Wide supply range: 2 to 36 V
- Input common-mode includes ground; up to VCC−1.5 V
- Outputs suitable for wired-OR and TTL/CMOS interfaces via pull-ups
- Low power consumption
- Temperature range: −40 °C to +125 °C (industrial)
- Fast switching (propagation delay on the order of microseconds, varies with VCC)
- Available in standard packages (e.g., DIP-8/SO-8) with QT packaging option
Note: Specifications vary by exact device variant and package.

- Pin count: 8 pins (DIP-8/SO-8).
- Function: Dual voltage comparator with open-collector outputs (two independent comparators, A and B). Each compares a non-inverting input (+) to an inverting input (−); outputs sink to ground and require pull-up resistors to Vcc. Supply typically 2–36 V.

The LM393QT is manufactured by Texas Instruments. TI is an American multinational semiconductor company that designs and manufactures analog and embedded processing integrated circuits, and is one of the world’s largest semiconductor makers.

LM393QT is a dual, low-power voltage comparator with open-collector outputs (2–36 V). Common application areas include:
- Threshold and level detection: undervoltage/overvoltage protection, battery monitoring, power-supply regulation
- Window detectors and level shifters for sensors
- Zero-crossing/AC line detection and PWM control
- Motor/fan speed sensing and protection
- Sensor interfacing: thermistors, photo sensors, gas/IR detectors for microcontrollers
- Automotive-grade sensing and alarms (QT variant)
- Simple oscillators/relaxation circuits with positive feedback for Schmitt-like behavior

LM393QT is an 8-pin surface-mount package, specifically an SOIC‑8 (Small Outline Integrated Circuit). Check the datasheet for the exact lead finish/variant (e.g., RoHS/compliant versions).