eeZ LED: Real-Time LED Tuner and Resistor Calculator (3.3V–24V)

Stop Calculating. Start Building.
Connect the LED (plug it in or wire it up). Turn the knob until it looks right.
The screen tells you the exact resistor value and wattage.

No datasheets. No guess-and-check. No burnt LEDs.

Built for engineers, technicians, and anyone who values their time.

White paper: https://drive.google.com/file/d/1KEsmdaaokYvFiiu6CklJ0g154uweEUtk/view?usp=sharing
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Why calculations LIE

Calculations tells you the minimum resistance to keep an LED alive. It tells you nothing about how that LED will look on your front panel, in daylight, or behind a diffuser.

The eeZ LED replaces the guess-and-check cycle with real visual feedback.
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WHAT IT DOES

• Measures your LED's actual forward voltage (Vf) — not the datasheet nominal
• Analog dimming from 300 µA to 25 mA: see the brightness before you build
• Calculates exact resistor value and minimum wattage for your chosen supply
• Auto-rounds to standard E96 1% values — the same series pros use
• Works with 3.3 V to 24 V systems (9 preset rails + custom)

One LED. One minute. Measure and GO.
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WHO IT'S FOR

Designed for professional use:

✓ Hardware Designers — Match intensity across batches, colors, and viewing angles
before committing to a PCB spin
✓ Embedded Engineers — Move from ESP32/STM32/Arduino prototype to production
schematic with verified values
✓ Repair Technicians — Match replacement LEDs without trial and error
✓ STEM Educators — Demonstrate Ohm's Law with real, measurable data
✓ Serious Hobbyists — Tired of experimenting and having to take your models apart each time?
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No multimeters. No thermal runaway. No "close enough."
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WHAT MAKES IT DIFFERENT

💡 True Analog Dimming — Clean DC, no PWM ripple or EMI. Safe for camera sensors and adjacent analog circuits.

💡 Auto-Calibrating — Dual voltage references (5V LDO + 1.1V bandgap) run a calibration routine at every power-up. No drift. No manual calibration. Ever.

💡 2.2 µA Resolution — Oversampled 14-bit ADC gives meaningful data even at sub-milliamp levels. Critical for battery-powered IoT and sleep-mode indicators.

💡 High-Contrast OLED — Readable in all bench lighting conditions.
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WHAT'S INCLUDED

• eeZ LED — fully assembled, calibrated, and tested
• Instructions for Use

NOTE: USB-C cable not included. Standard phone charger or battery bank compatible.
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HAND-ASSEMBLED & TESTED

Each eeZ LED is hand-assembled, individually tested, and calibrated before shipping.
No mass production — just a tool built by someone who uses it.
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📢 Q and A

Q: Why not just use an online resistor calculator or a table of LED forward voltages?
A: Calculators and tables assume a nominal Vf. Real LEDs vary by batch, chemistry, temperature, and color. The eeZ LED measures your actual LED at your actual current and gives you the resistor for the brightness you see.

Q: Why analog instead of a PWM dimmer?
A: PWM introduces switching noise and can confuse camera sensors or adjacent analog circuits. The eeZ LED uses a true analog constant-current source — clean DC, no ripple, no EMI.

Q: Do I need to calibrate it?
A: No. Auto-calibration at every power-up using dual voltage references.
Factory-tested, field-stable.

Q: Why does it show a "weird" resistor value like 102 Ω instead of 100 Ω?
A: The eeZ LED rounds up to the next standard E96 1% value. This guarantees your
LED runs at or below the tuned brightness, accounting for tolerance and drift.

Q: Do I really need 2.2 µA resolution?
A: If you design battery-powered IoT, sleep-mode indicators, or any low-current LED,
yes. Sub-milliamp characterization is where cheap LED testers fall apart.