LM393 Dual Comparator IC – Low Power, Wide Voltage Range
LM393 Dual Comparator IC – Low Power, Wide Voltage Range
The LM393 is a dual differential comparator designed to operate from a single or split power supply. It compares two input voltages and outputs a digital signal based on which is higher. With a wide supply voltage range, low current drain, and open-collector outputs, it's a go-to IC for signal conditioning, level detection, and voltage monitoring in embedded systems.
Key Specifications
| Specification | Value |
|---|---|
| Supply Voltage | 2V to 36V (single) or ±1V to ±18V (dual) |
| Input Offset Voltage | Typically 2mV |
| Input Bias Current | 25nA (typical) |
| Output Type | Open Collector (requires pull‑up) |
| Number of Comparators | 2 |
| Package | DIP‑8 (through‑hole) |
What You Can Build With This
- Window comparator for battery voltage monitoring
- Overvoltage protection circuit with relay driver
- Light/dark detection threshold switch
- Zero‑crossing detector for AC signal processing
Compatibility
The LM393 operates over a supply range that matches common 3.3V and 5V logic levels, making it suitable for direct connection to Arduino, Raspberry Pi, or ESP32 boards. Its open‑collector outputs can sink up to 16mA, allowing direct drive of small relays or LEDs with a pull‑up resistor. It's often paired with transistor or MOSFET drivers for higher current loads.
Wiring Notes
Connect Vcc (pin 8) to your positive supply and GND (pin 4) to ground. Apply input signals to the non‑inverting (pins 3,5) and inverting (pins 2,6) terminals. Outputs (pins 1,7) require a pull‑up resistor (typically 4.7kΩ to 10kΩ) to Vcc to obtain a high logic level. Keep input voltages within the common‑mode range (0V to Vcc−1.5V) for reliable operation.
Why Buy from Compoden
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Is this compatible with Arduino Uno?
Yes, you can power the LM393 from the Arduino's 5V pin. Connect its output to any digital input; a 10kΩ pull‑up resistor to 5V is needed for proper logic levels.
How do I use it as a zero‑crossing detector?
Set one input to ground and the other to your AC signal through a series resistor. The output will toggle on each zero crossing; a software debounce may be required.
What pull‑up resistor value should I choose?
A 4.7kΩ resistor is a good starting point for most applications. Lower values increase speed but draw more current; a 10kΩ value works well for low‑speed logic interfacing.
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Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items