UTP3303 3Ch Linear Power Supply

UNI-T UTP3303 Three-Channel Linear DC Power Supply

Precision Variable Power with Dual Adjustable Channels and Fixed 5V Output

The UNI-T UTP3303 is a professional three-channel linear DC power supply delivering precise, low-noise power for electronics development, testing, and repair. With dual independently adjustable channels providing 0-32V at 0-3A and a fixed 5V/3A output, this 207W power supply delivers the stable, clean power essential for sensitive electronic circuits. Featuring ultra-low ripple noise (≤1mVrms for constant voltage, ≤3mArms for constant current), exceptional load regulation, and automatic constant voltage/constant current mode switching, the UTP3303 provides the precision and reliability needed by electronics engineers, technicians, educational laboratories, and repair professionals working with analog circuits, digital systems, embedded development, and precision instrumentation.

Key Features

• Three Independent Channels: Two adjustable 0-32V/0-3A channels plus fixed 5V/3A output
• 207W Total Power Output: Ample power for most electronics development and testing
• Ultra-Low Ripple and Noise: ≤1mVrms (CV) and ≤3mArms (CC) for sensitive circuits
• Linear Design: Clean, noise-free power superior to switching supplies
• Dual 3-Digit Displays: Simultaneous voltage and current monitoring per channel
• Automatic CV/CC Mode Switching: Seamless transition with current limit protection
• Master-Slave Tracking: CH1 and CH2 tracking capability for synchronized outputs
• Series/Parallel Operation: Combine channels for higher voltage or current
• Exceptional Load Regulation: CV≤1×10⁻⁴+3mV, CC≤2×10⁻⁴+3mA
• Over-Current and Over-Voltage Protection: Comprehensive safety for connected circuits

Laboratory-Grade Linear Power Supply for Precision Applications

The UNI-T UTP3303 utilizes linear regulation technology to deliver exceptionally clean, stable power that is essential for sensitive electronic applications. Unlike switching power supplies that introduce high-frequency noise and ripple, the UTP3303's linear design provides pure DC power with minimal interference. With ripple and noise specifications of just 1mVrms in constant voltage mode and 3mArms in constant current mode, this power supply ensures that your measurements, test results, and circuit behavior remain unaffected by power supply artifacts.

The exceptional load regulation performance (CV≤1×10⁻⁴+3mV for voltage, CC≤2×10⁻⁴+3mA for current) means the output remains stable regardless of load changes, providing consistent power whether your circuit draws minimal current or approaches the full 3A rating. This stability is critical for precision measurements, audio circuit development, and any application where power supply variations could affect circuit performance or introduce measurement errors.

Comprehensive Three-Channel Configuration

The UTP3303's three-channel design provides exceptional flexibility for complex testing and development scenarios:

• Channel 1 and 2: Fully adjustable 0-32V at 0-3A with independent control and monitoring
• Channel 3: Fixed 5V at 3A for powering logic circuits, microcontrollers, and digital systems
• Independent Operation: Run all three channels simultaneously with different voltage and current settings
• Tracking Mode: Link CH1 and CH2 for synchronized dual-polarity supplies
• Series Connection: Combine channels for up to 64V output capability
• Parallel Connection: Combine channels for up to 6A current capacity

This versatility makes the UTP3303 ideal for powering mixed analog/digital circuits, testing multi-voltage systems, providing dual-polarity supplies for op-amp circuits, and handling complex development boards that require multiple supply voltages simultaneously. The 3A per channel rating is perfectly suited for most microcontroller development, analog circuit prototyping, and general electronics work.

Automatic Constant Voltage/Constant Current Operation

The UTP3303 automatically switches between constant voltage (CV) and constant current (CC) modes based on load conditions, providing intelligent power delivery and protection:

• Constant Voltage Mode: Maintains precise voltage output while current varies with load
• Constant Current Mode: Limits current to preset value, protecting circuits from overcurrent
• Automatic Mode Switching: Seamless transition between CV and CC based on load requirements
• Current Limit Protection: Set maximum current to protect sensitive components during testing
• Visual Mode Indication: Clear display indicators show active operating mode

This automatic operation is particularly valuable when powering unknown or prototype circuits, testing battery charging algorithms, characterizing component behavior under current-limited conditions, or protecting expensive devices from accidental overcurrent damage. The 3A current limit per channel provides ample protection for typical development and testing scenarios while preventing damage to sensitive components.

Professional Applications

Electronics Development and Prototyping

Design engineers and developers rely on the UTP3303's clean power and flexible configuration for:

• Powering breadboard circuits and development boards
• Testing prototype designs under controlled voltage and current conditions
• Providing dual-polarity supplies for analog circuit development
• Characterizing component behavior across voltage and current ranges
• Simulating battery discharge characteristics with current limiting

Educational and Training Laboratories

Educational institutions utilize the UTP3303's multiple channels and safety features for:

• Student electronics experiments and circuit analysis
• Demonstrating voltage and current relationships in active circuits
• Teaching constant voltage and constant current concepts
• Providing safe, current-limited power for student projects
• Supporting multiple power requirements in single experiments

Electronics Repair and Service

Service technicians depend on the UTP3303's precision and protection for:

• Powering and testing repaired circuits before reassembly
• Performing current consumption analysis to identify faulty components
• Testing power supply circuits with precisely controlled loads
• Providing clean power for sensitive audio and video equipment testing
• Charging and testing battery-powered devices under controlled conditions

Embedded Systems and Microcontroller Development

Embedded developers leverage the UTP3303's multiple outputs for:

• Powering microcontroller development boards with fixed 5V output
• Providing adjustable voltage for testing circuit operation across supply range
• Simultaneous power for processor core, peripherals, and sensor modules
• Current monitoring to optimize battery-powered device power consumption
• Testing system behavior under varying supply voltage conditions

Technical Specifications

General Specifications

• Input Voltage: 115V AC/230V AC (switchable)
• Input Frequency: 47Hz-63Hz
• Display Type: Dual 3-digit LED display per channel
• Operating Features: Automatic CV/CC mode switching with current limit protection, CH1 and CH2 master-slave tracking capability
• Configuration Options: Series connection (up to 64V), Parallel connection (up to 6A)
• Product Color: White and grey professional chassis
• Product Net Weight: 8.7kg (19.2 lbs)
• Product Dimensions: 260mm × 170mm × 315mm (10.2" × 6.7" × 12.4")
• Cooling: Forced air cooling with internal fan

Package Contents

• UNI-T UTP3303 Three-Channel Linear DC Power Supply
• Power Cord (suitable for your region)
• Output Cables (banana plug to alligator clip sets)
• User Manual

Product Comparison

Frequently Asked Questions

What is the difference between linear and switching power supplies, and why does it matter?

Linear power supplies like the UTP3303 use transformer-based regulation to provide exceptionally clean DC power with minimal ripple and noise. This design produces pure, stable power that won't interfere with sensitive measurements or introduce artifacts into analog circuits. Switching power supplies, while more compact and efficient, generate high-frequency noise from their switching circuitry that can affect analog circuits, interfere with radio frequency applications, and create measurement errors in precision instruments. For applications requiring the cleanest possible power, development work with analog circuits, audio equipment testing, or precision measurement scenarios, the linear design's superior noise performance justifies the larger size and weight.

How do I use the tracking mode between Channel 1 and Channel 2?

The UTP3303's tracking mode links Channel 1 and Channel 2 in a master-slave configuration, allowing both channels to track together for creating dual-polarity power supplies essential for operational amplifier circuits and other analog applications. When tracking is enabled, adjusting the voltage on the master channel causes the slave channel to follow automatically, maintaining synchronized output. This feature is particularly useful for providing matched positive and negative supply rails for audio circuits, instrumentation amplifiers, or any application requiring symmetrical bipolar power supplies. The tracking bias specification of 5×10⁻³+10mV ensures the channels remain closely matched even as you adjust voltage levels.

What happens when I exceed the current limit in constant current mode?

When operating in constant current mode, the UTP3303 automatically limits the output current to your preset value, allowing the voltage to drop as necessary to maintain that current level. This provides excellent protection for circuits under test because if a short circuit or unexpected low-resistance condition occurs, the power supply will reduce voltage rather than delivering damaging current levels. The display will clearly indicate CC mode operation, and you'll see the voltage decrease while current remains at your set limit. This makes constant current mode ideal for testing unknown circuits, charging batteries with controlled current, or protecting sensitive components during development and troubleshooting.

Can I connect the channels in series or parallel for higher voltage or current?

Yes, the UTP3303 supports both series and parallel configurations of Channels 1 and 2 to extend capability beyond single-channel specifications. In series configuration, you can achieve up to 64V output by adding the voltages of both channels, which is useful for testing circuits designed for higher voltage industrial or automotive applications. In parallel configuration, you can combine the current capacity of both channels to achieve up to 6A output while maintaining the voltage setting, ideal for powering higher-current loads or testing power supply circuits. The user manual provides detailed connection diagrams and safety precautions for these configurations, ensuring proper operation and protection of both the supply and your circuits.

Is 3A per channel sufficient for most electronics work?

For the vast majority of electronics development, repair, and educational applications, 3A per channel provides ample power capacity. Most microcontroller development boards, analog circuits, sensor modules, and prototyping projects draw well under 1A, making the UTP3303's 3A rating more than sufficient with comfortable headroom. Common applications like Arduino boards typically draw 50-200mA, Raspberry Pi boards draw 500mA-2.5A depending on peripherals, and typical op-amp circuits draw just a few milliamps. The ability to parallel the channels for 6A combined output handles even more demanding applications when needed. If you're regularly working with high-power motor controllers, charging large battery packs, or testing power amplifier circuits that consistently require more than 3A, the UTP3305's 5A rating would be more appropriate.

Why would I need three independent channels instead of a single-channel power supply?

Modern electronic systems frequently require multiple supply voltages simultaneously: microcontrollers need 5V or 3.3V logic power, analog circuits require dual positive and negative supplies, and sensor modules often run on different voltages than the main processor. The UTP3303's three-channel design eliminates the need for multiple separate power supplies on your bench, reduces cable clutter, and ensures all your power sources share a common ground reference. The fixed 5V/3A Channel 3 is particularly convenient for digital circuits and development boards, while the adjustable Channels 1 and 2 provide flexibility for analog circuits, testing across voltage ranges, or providing dual-polarity supplies. This consolidation saves bench space, reduces cost compared to multiple separate supplies, and simplifies your test setup.

What is the warranty period for the UNI-T UTP3303?

The UTP3303 includes our Exclusive 3+2 Warranty program. You receive a standard 3-year warranty covering manufacturing defects and component failures under normal use conditions. Register your power supply on our website within 30 days of purchase to receive an additional 2 years of coverage at no cost, for a total of 5 years of protection. This comprehensive warranty ensures your investment in professional test equipment is protected, giving you confidence in your purchase decision.

Support and Warranty

UNI-T stands behind the UTP3303 with comprehensive technical support and our Exclusive 3+2 Warranty program (3 years standard, plus 2 additional years free with product registration). Our dedicated support team is available to assist with configuration questions, application support, and warranty service.

Professional Linear Power for Demanding Applications

The UNI-T UTP3303 Three-Channel Linear DC Power Supply delivers exceptional precision, stability, and flexibility for professional electronics development, testing, and repair. With its three independent outputs including dual adjustable 0-32V/0-3A channels and fixed 5V/3A output, ultra-low ripple and noise specifications, and comprehensive operating modes including tracking and series/parallel configurations, it provides the clean, stable power essential for sensitive electronics work. The 207W total power capacity, excellent load regulation, and automatic CV/CC mode switching make the UTP3303 the ideal power solution for engineers, technicians, and educational laboratories who need professional performance at an accessible price point.

Order Your UNI-T UTP3303 Today and Experience Professional-Grade Linear Power Supply Performance