UNI-T UDP3305S Performance Series Programmable Linear DC Power Supply
Overview
The UNI-T UDP3305S is a 4-channel programmable linear DC power supply with 1 mV / 1 mA setting resolution, 328W total output, and full automation-grade connectivity — USB-Host, LAN, RS-232, and Digital I/O. CH1 and CH2 deliver 0–30V at up to 5A independently or in software-routed series (up to 60V) or parallel (up to 10A) without external wiring. CH3 provides a 0–6V/3A logic-level channel. The linear topology holds output ripple under 350 µVrms (5 Hz–1 MHz) — clean enough for sensor-bridge excitation, ADC reference rails, and any work where switching-supply artifacts would land in the measurement budget.
For embedded prototyping, sensor characterization, automated test integration, and R&D workflows where 1 mV setpoint precision matters, the Performance-Series tier is the target configuration of the UDP3000S platform. The 4.3-inch TFT displays voltage, current, and power waveforms in real time across all configured channels — transient load behavior, inrush events, and power-up sequences are visible at the supply itself, no oscilloscope required for routine power-behavior observation.
UDP3305S — 4-channel programmable linear bench supply with 1 mV / 1 mA setting resolution
Across the Design. Debug. Deploy.™ Lifecycle
Across the design-debug-deploy lifecycle: Design. Four isolated linear-topology channels at low ripple set the bias and supply rails that analog and sensor designs need from first prototype. Debug. 1 mV / 1 mA setting resolution and series/parallel/tracking modes characterize multi-rail DUT behavior under load. Deploy. SCPI over USB and LAN with web control drive production characterization without leaving the supply’s front panel. Affordability meets precision — design, debug, deploy.
Key Features
- 1 mV / 1 mA Setting Resolution Across All Channels — 5-digit voltage / 4-digit current readout. Displayed value is the actual programmed value, not a rounded approximation. 10× finer voltage resolution than the Advanced-Series tier UDP3305S-E.
- 4 Fully Isolated Channels (328W Total) — CH1 & CH2: 0–30V/5A independent; CH3: 0–6V/3A logic-level; CH4: 5V/2A USB charging output. Channel grounds are isolated — connect them where you need them, leave them floating where the test demands it.
- One-Key Series and Parallel — Software-routed combination of CH1 + CH2: up to 60V in series or 10A in parallel without external wiring between channel terminals. No jumper cables, no shorting bars, no risk of miswiring.
- Linear Topology, < 350 µVrms Ripple — Linear pass-element regulation, not a switching converter. Output ripple stays under 350 µVrms (5 Hz–1 MHz) and 2 mVpp peak-to-peak. Line and load regulation hold inside 0.01% + 2 mV.
- 4.3-Inch TFT with Real-Time Waveform Display — Plots voltage, current, and power waveforms across all configured channels simultaneously. Inrush, transient steps, and power-up sequences visible at the supply itself.
- List Output and Delayer Functions — Programmable voltage/current waveforms with built-in templates (sine, ramp, pulse). 10 list profiles + 10 delayer files + 5 preset configurations.
- SCPI over LAN, RS-232, USB-Host + Web Server Browser Control — Full automation reach plus driverless web-page control from any laptop on the same subnet.
- External Trigger via Digital I/O — Hardware input/output trigger lines for cross-instrument timing coordination beyond software loops.
- OVP / OCP / OTP with Configurable Monitor — Per-channel protection with free-form trigger condition (V/I/P upper limits, OR logic) and selectable response (output off, beeper, both). Voltage/current limit caps for guarded operation. Keyboard lock prevents accidental reconfiguration.
- Industry-leading 3+2 Warranty — Three-year standard plus two additional years with free registration. Free firmware updates over the product's lifetime.
Detailed Features
1 mV / 1 mA Setting Resolution
1 mV voltage and 1 mA current setting resolution across all four channels — fine enough to bias an op-amp test fixture exactly at threshold, set a precise battery-charge cut-off, or characterize sleep-mode current draw on an IoT sensor without resorting to a separate source-meter. The 5-digit voltage / 4-digit current readout matches the setting resolution end-to-end so the displayed value is the actual programmed value, not a rounded approximation.
UDP3305S 4.3-inch TFT — voltage, current, and power readouts plus configured limits in one view
Linear Topology < 350 µVrms Output Ripple
Linear pass-element regulation, not a switching converter — output ripple stays under 350 µVrms (5 Hz–1 MHz) and 2 mVpp peak-to-peak. Line and load regulation hold inside 0.01% + 2 mV. For low-noise analog work, sensor-bridge excitation, ADC reference rails, and any measurement that lives close to its noise floor, the linear topology is the difference between a clean signal and chasing supply artifacts. Transient response under 50 µs handles real load steps; the 10 ms command processing time keeps automated sweeps responsive.
UDP3305S — one-key series (60V) or parallel (10A) combination of CH1 + CH2
Real-Time Voltage / Current / Power Waveform Display
The 4.3-inch TFT LCD plots voltage, current, and power waveforms in real time across all configured channels — every channel, simultaneously. Inrush events, load steps, and power-up transients are visible directly on the supply's display, no oscilloscope required for routine power-behavior observation. Set/limit values for voltage, current, OVP, and OCP all appear next to live readouts so the configuration and the actual output stay on one screen.
Real-time V/I/P waveform display across all configured channels
List Output and Delayer Functions
The list function generates programmable voltage and current waveforms with up to 10 stored list profiles per supply. Built-in templates (sine, ramp, pulse) accelerate setup; the editor lets you define waveform points, dwell intervals, voltage/current limits, and inversion freely. The delayer function adds programmable on/off sequencing — useful for power-on/off reliability testing, sequenced rail bring-up, and stress cycling. 10 delayer files plus 5 preset configurations keep frequently used setups one keypress away.
List output editor — sine/ramp/pulse templates, programmable dwell intervals
External Trigger via Digital I/O
The rear-panel digital I/O port supports input-trigger mode (external systems control the supply remotely — toggle outputs, advance through list steps, change channels) and output-trigger mode (the supply provides trigger pulses and status flags to drive other instruments in a coordinated test setup). Falling-edge / rising-edge triggering and selectable response (output toggle, output on, output off) cover the common automation patterns directly without an additional sequencer.
SCPI over LAN, RS-232, USB — and Web Server Browser Control
SCPI command control runs over LAN, RS-232, and USB-Host. The built-in Web Server adds browser-based remote control: any laptop or workstation on the same subnet operates the front panel through a web page — no driver install, no application. Combined with included PC software, the UDP3305S drops into existing automated test environments and serves remote-bench scenarios where the rack-mount supply isn't physically accessible. Digital I/O adds hardware trigger lines for tighter timing coordination than software loops alone.
Rear-panel data interfaces: USB-Host, LAN, RS-232, Digital I/O
OVP / OCP / OTP with Configurable Monitor Conditions
Per-channel over-voltage protection, over-current protection, and over-temperature protection guard the device under test. The Monitor function allows free configuration of the protection trigger condition (V upper limit, I upper limit, P upper limit, with logical OR combination) and the response — output off, warning beeper, or both. Voltage and current limit functions cap the adjustable range for guarded teaching-lab or operator-supervised configurations. Keyboard lock prevents accidental reconfiguration during an unattended run.
Intelligent Fan Control and Channel Isolation
Fan speed adjusts automatically with internal temperature, keeping noise low at light loads and ramping up only when the chassis needs the airflow. All four channels are fully isolated from each other — connect grounds where you need them, leave them floating where the test demands it. CH1+CH2 one-key series and parallel modes use software-routed combination, no external wiring required between the channel terminals.
UDP3305S rear panel — data interfaces, AC input, fan exhaust, protected ground
Detailed Specifications
| Output Topology | DC Linear |
| Output Channels | 4 channels |
| Headline Voltage | 30V |
| Headline Current | 5A |
| Total Output Power | 328W |
| Voltage Resolution | 1 mV |
| Current Resolution | 1 mA |
| Programmable | Yes (SCPI command set) |
| Touch Screen | No |
| Data Interface | USB-Host, LAN, RS-232, Digital I/O |
| Certifications | CE |
| RoHS Compliant | Yes |
| Warranty | 3+2 years |
Applications
R&D Engineering
Precision-resolution programmable bench power for embedded prototyping, sensor characterization, and analog circuit development — 1 mV resolution and <350 µVrms ripple keep the supply out of the noise budget.
- IoT sensor sleep-mode current measurement (1 mA resolution at the supply, no external shunt required)
- Op-amp / instrumentation amplifier bias point sweeps with 1 mV step granularity
- Multi-rail embedded designs — digital core (CH3 logic level), analog front-end, I/O, and sensor power simultaneously from one chassis
- Battery-charge curve emulation via list output, with delayer for power-cycle reliability runs
Test Lab / Consultancy
Multi-channel automation-grade bench supply for contract test labs and engineering consultancies — SCPI over LAN/RS-232/USB plus Web Server browser control means it integrates with whatever automation framework the lab runs.
- Drop-in replacement for ageing programmable linears in existing test stations
- Web Server browser control for remote-bench access without driver install
- 5 preset configurations + 10 list profiles + 10 delayer programs cover stored sequences for frequent test rotations
- Digital I/O hardware trigger for tight cross-instrument timing
Power Electronics Engineering
Linear topology removes switching-supply confounds when characterizing low-power analog rails, sensor frontends, and gate-drive auxiliary supplies in power-electronics designs — combined with the waveform display, transient behavior is visible without a separate scope.
- Auxiliary rail emulation (bias supply for gate drivers, sense-amp Vcc, ADC reference)
- Real-time waveform display catches inrush and transient events at the supply itself
- CH1+CH2 series mode delivers up to 60V for higher-bias analog work
- OVP/OCP with configurable Monitor protects the DUT during automated sweeps
Accessories & In the Box
Included
- UDP3305S
- Power cord (matched to country of destination)
- USB data cable
- Quick-start guide
Optional
- Alligator-clip test leads (replacement / additional)
- Rack-mount kit (if applicable to deployment)
Frequently Asked Questions
What's the difference between the UDP3305S and the UDP3305S-E?
Identical hardware platform — same 4-channel chassis, same 328W headline, same one-key series/parallel, same SCPI over LAN/RS-232/USB-Host, same Web Server browser control, same OVP/OCP/OTP, same real-time waveform display. The difference is voltage setting resolution: UDP3305S has 1 mV resolution; UDP3305S-E has 10 mV. For embedded prototyping, sensor characterization, and analog work where setpoint precision is part of the measurement budget, the UDP3305S Performance tier is the target. For teaching labs, multi-station deployments, and R&D benches where 10 mV resolution suffices, the UDP3305S-E is the same hardware at 10 mV resolution (Advanced-Series budget tier).
Is the front-panel USB port a data interface?
No — the front-panel USB-A connector on CH4 is a fixed 5V/2A USB charging output for powering devices under test directly. It is not a data interface. The data interfaces are on the rear panel: USB-Host (data), LAN, RS-232, and Digital I/O.
Data Sheets and Manuals
Software / Firmware Downloads
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