KY-028 Digital Temperature Sensor Module – NTC LM393 for Arduino

KY-028 Digital Temperature Sensor Module with LM393 for Arduino

Buy the KY-028 Digital Temperature Sensor Module with LM393 online in Pakistan from Robostan.pk. This compact temperature detection module features an NTC thermistor, an LM393 comparator, adjustable temperature threshold control, and both analog and digital outputs.

Designed for Arduino, ESP32, Raspberry Pi, robotics, IoT, and DIY electronics projects, the KY-028 is suitable for monitoring temperature changes and detecting when a selected temperature threshold is reached.

The module uses a Negative Temperature Coefficient (NTC) thermistor whose electrical resistance decreases as temperature increases. Its analog output provides a temperature-dependent signal, while the LM393 comparator generates a digital switching output based on the threshold adjusted using the onboard potentiometer.

Key Features

• KY-028 NTC temperature sensing module
• Integrated LM393 voltage comparator
• Analog temperature sensing output (AO)
• Digital temperature threshold output (DO)
• Adjustable threshold using onboard potentiometer
• Typical operating voltage of 3.3V to 5V DC
• NTC thermistor with resistance decreasing as temperature increases
• Commonly specified thermistor sensing range of -55°C to +125°C
• Four-pin interface for simple microcontroller connections
• Onboard power and threshold indicator LEDs
• Compatible with Arduino UNO, Nano and Mega
• Suitable for ESP32 and STM32 with appropriate connections
• Usable with Raspberry Pi through digital GPIO or external ADC
• Compact PCB design for embedded applications
• Suitable for temperature alarm and monitoring projects

Technical Specifications

• Product Name: KY-028 Digital Temperature Sensor Module
• Model Number: KY-028
• Sensor Type: NTC Thermistor
• Comparator IC: LM393
• Supply Voltage: Typically 3.3V to 5V DC
• Nominal Thermistor Range: -55°C to +125°C
• Output Type: Analog and Digital
• Analog Output: Temperature-Dependent Voltage
• Digital Output: Comparator-Based HIGH/LOW Signal
• Threshold Adjustment: Onboard Potentiometer
• Indicator LEDs: Power and Detection Status
• Interface: Four-Pin Header
• Pin Labels: AO, GND, VCC and DO (depending on PCB layout)
• Measurement Principle: NTC Resistance Variation
• Digital Threshold: Adjustable
• Compatible Controllers: Arduino, ESP32, STM32 and Raspberry Pi with Suitable Interfacing
• Mounting Type: PCB Sensor Module

Applications

• Arduino temperature monitoring projects
• Temperature threshold detection
• Overtemperature warning prototypes
• Temperature-triggered fan control
• Robotics and automation systems
• ESP32 IoT temperature monitoring
• Electronic thermostat experiments
• Temperature alarm circuits
• Smart home monitoring prototypes
• Educational sensor experiments
• Microcontroller analog input projects
• Embedded electronics temperature sensing
• Heating and cooling control demonstrations

How Does the KY-028 Temperature Sensor Work?

The KY-028 Temperature Sensor measures temperature changes using an NTC thermistor.

As temperature increases, the thermistor resistance decreases. The module converts this resistance change into an analog voltage signal.

The analog signal can be read through the analog-to-digital converter (ADC) of a compatible microcontroller.

The KY-028 also includes an LM393 comparator that compares the temperature-dependent signal with an adjustable reference voltage.

When the comparator threshold is crossed, the digital output changes state. This allows the controller to detect a temperature event without continuously calculating an exact temperature value.

Dual Analog and Digital Outputs

The KY-028 provides two output options:

• AO (Analog Output): Produces a voltage that varies with thermistor temperature. A controller can convert the reading into an estimated temperature using suitable calibration and thermistor equations.
• DO (Digital Output): Produces a HIGH or LOW signal when the adjustable threshold is crossed.

The analog output is useful for temperature measurement experiments, while the digital output is convenient for alarms and temperature-triggered switching.

Adjustable Temperature Threshold

The onboard potentiometer allows users to adjust the comparison threshold of the LM393 circuit.

By rotating the potentiometer, the switching point can be selected for an electronic alarm, notification system, or suitable control circuit.

Note: The potentiometer does not directly display or set a calibrated temperature in degrees Celsius. Use a thermometer and suitable calibration procedure when a specific switching temperature is required.

KY-028 Module Pinout

• AO: Analog temperature-dependent output
• GND: Ground connection
• VCC: Positive DC supply voltage
• DO: Digital temperature-threshold output

Pin order varies between manufacturers. Follow the markings printed on the actual PCB before connecting the module.

Arduino Compatibility

The KY-028 LM393 Temperature Sensor Module is compatible with Arduino UNO, Nano, Mega and other suitable development boards.

A typical Arduino UNO connection is:

• KY-028 VCC: Arduino 5V
• KY-028 GND: Arduino GND
• KY-028 AO: Arduino A0
• KY-028 DO: Arduino D3

The Arduino can use analogRead() to monitor analog voltage changes and digitalRead() to detect the comparator output state.

For example, the module can activate a buzzer or LED when a temperature threshold is crossed.

ESP32 and Raspberry Pi Compatibility

The KY-028 can be integrated with ESP32 and other compatible 3.3V microcontrollers using suitable voltage levels.

For Raspberry Pi applications, its digital output can be monitored using a GPIO input.

Reading the analog output with a standard Raspberry Pi requires an external ADC, such as an MCP3008 or ADS1115, because Raspberry Pi GPIO pins do not provide built-in analog inputs.

KY-028 vs KY-013 Temperature Sensor

The KY-028 and KY-013 both use NTC thermistors but offer different features.

• KY-013: Simple three-pin analog temperature sensor module.
• KY-028: Four-pin temperature sensor module with analog output, LM393 comparator, adjustable threshold and digital output.

Choose the KY-028 when a temperature threshold indicator or digital switching output is needed alongside analog temperature information.

Why Choose the KY-028?

Dual Output: Provides both analog temperature information and digital threshold detection.

Adjustable Switching Point: The onboard potentiometer allows threshold adjustment without modifying program code.

Simple Integration: Connects to common microcontrollers through analog and digital inputs.

Compact Design: Suitable for small electronic circuits and prototyping projects.

Educational Value: Useful for learning about NTC thermistors, voltage dividers, comparators and temperature control.

Important Usage Notes

• The KY-028 is an NTC thermistor module with an LM393 comparator.
• The digital output indicates threshold crossing; it does not provide a numerical temperature reading.
• The analog output requires suitable calibration for temperature conversion.
• Measurement accuracy depends on thermistor tolerances, circuit components and calibration.
• Do not assume the entire PCB assembly is rated for continuous use at 125°C.
• The module is not waterproof and is not intended for immersion in liquids.
• Use suitable voltage levels for 3.3V-only microcontrollers.
• Verify the actual board pinout and digital output polarity before use.
• Do not connect the module directly to AC mains.
• Do not connect high-current loads directly to the sensor outputs.
• For motor or fan control, use a suitable external driver or relay module.
• This hobby module should not be the sole protective device in safety-critical temperature systems.

Package Contents

• 1 x KY-028 Digital Temperature Sensor Module with LM393

Buy KY-028 Digital Temperature Sensor in Pakistan

Looking for a KY-028 Digital Temperature Sensor Module with LM393 in Pakistan? Shop online at Robostan.pk for Arduino sensors, NTC thermistor modules, ESP32 accessories, Raspberry Pi components, robotics parts and electronics project supplies.

The KY-028 is suitable for students, engineers, makers and electronics enthusiasts developing temperature sensing and automation projects.

Order your KY-028 LM393 Temperature Sensor Module from Robostan.pk with nationwide delivery across Pakistan, including Lahore, Karachi, Islamabad, Rawalpindi, Faisalabad, Multan, Peshawar and other cities.

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