Semi Otter Edu SEMI OTTER EDU Co., Ltd.

A USB device measurement system for the classroom

OTTER I-V

Plug it into a laptop over USB and measure the device sitting on the breadboard.

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Otter I-V unit, with blue, green, red and black banana jacks on the front
±10 V
Source voltage
±8 mA
Measured current
8 routines
From diodes to memristors
USB
Bus powered · no separate adapter
8 measurement routines · test devices

From diodes to memristors, with off-the-shelf devices

The PC application and the tablet screen offer the same eight measurements with the same settings. The three memristor routines were added in application v1.2.0 in 2026.

RoutineWhat it measuresTypical devices
I-VSweeps the voltage and measures the current. Single, double or cycle sweepResistors, diodes, LEDs, memristors
FET TransferTransfer characteristic against gate voltage at a fixed drain voltagen- and p-type MOSFETs
FET OutputDrain current against drain voltage, stepping the gate voltagen- and p-type MOSFETs
BJT CollectorFamily of collector curves, stepping the base currentNPN and PNP transistors
I-tCurrent against time at a constant voltagePhotoresistors and other light-sensitive devices
RetentionWhether a state written by a pulse holds over timeMemristors
EnduranceRepeats SET, read, RESET, read and tracks the resistance windowMemristors
P-DConductance change under repeated identical pulses (potentiation and depression, LTP / LTD)Memristors, synaptic devices
Test devices included
  • Resistors 0.1, 1 and 10 kΩ — Ohm's law, series resistance
  • Light-emitting diode — rectification, threshold voltage
  • CD4007 — n-MOSFET transfer and output characteristics
  • BC546 — NPN BJT collector characteristics
  • Photoresistor — light and resistance, I-t

They plug straight into the breadboard. Being commodity parts, consumables cost little.

Four lab handouts

A semester of lab work comes with the instrument

There is no need to write handouts from scratch. A semester's worth of handouts written for Otter I-V and the included test devices is supplied with it. Every graph below was measured with Otter I-V.

Lesson 1

Diodes and LEDs

Current-voltage characteristics of an LED and a 1 kΩ resistor on a log axis
Students find the threshold voltage themselves
Lesson 2

MOSFET

Output characteristic curves of a CD4007 n-MOSFET
Gate voltage and drain current
Lesson 3

BJT

Collector characteristic curves of a BC546 NPN transistor
Base current and current gain
Lesson 4

Semiconductors and light

Current against time of a CdS photoresistor at 1 V while it is covered and then lit with a torch
Current that follows the light
How a handout is built

Theory → Objective → Guide → Measure and analyse

Every lesson follows the same order. The diode lesson is shown below as an example.

1 · Theory

How a P-N junction works

Theory page of the diode handout: energy band diagram of a P-N junction and the built-in potential (in Korean)
Explained with energy bands
2 · Objective

Circuit, quantities, analysis

Objective page of the diode handout: circuit diagram of Otter I-V with an LED and a 1 kΩ resistor (in Korean)
Sets the circuit and what to extract
3 · Guide

Breadboard wiring

Guide page of the diode handout: where to plug the LED and resistor on the breadboard and how to wire them to the red and black jacks (in Korean)
Shows where each part goes
4 · Measure and analyse

Students measure for themselves

They open the csv in a spreadsheet or Python, find the threshold voltage and fit the ideal diode equation.

Lesson plan

  1. 0Ohm's law primerCourse introduction · resistors and first measurements
  2. 1DiodeP-N junction · LED
  3. 2MOSFETCD4007 transfer and output
  4. 3BJTBC546 collector characteristics
  5. 4Semiconductors and lightPhotoresistor · light
  6. +MemristorRetention · endurance · potentiation and depression (supplementary)

See the lab handouts

Otter I-V unit and test devices in the ABS case
What is in the box

Instrument, devices and handouts together

  • Otter I-V unit, USB cable, USB A to C adapter
  • Banana-to-jumper cables, breadboard
  • Test devices — resistors 0.1 / 1 / 10 kΩ, light-emitting diode, CD4007, BC546, photoresistor
  • Software on a USB stick, four lab handouts
  • ABS case — holds the unit and the accessories

Your university or department logo is printed on the unit when you order.

Units are kept in stock and ship within five business days of the order. Please check with us first for large orders.

PC or tablet

An application on the PC, a browser on the tablet

The tablet opens the instrument in a browser with no app to install. Both offer the same measurements.

The same MOSFET output curves shown in the Otter I-V application on a laptop and in a tablet browser
  • USB — measure with the Windows 10 / 11 application and save the result as csv.
  • Wireless — the instrument opens its own wireless network and serves the control screen itself. Open it from the browser of an iPad, an Android tablet or a laptop.

Connecting a tablet in three steps

  1. Join the instrument's Wi-Fi
    The instrument creates the network itself. No router and no internet connection are needed.
  2. Enter 192.168.4.1 in the browser
    The control screen lives inside the instrument, so there is nothing to install.
  3. Measure → csv and png saved automatically
    The data and the graph land in the tablet's Download folder.

Wireless works the same

  • No computer, no installation and no internet connection.
  • A 100-point measurement takes 2.4 s, the same as over USB.
  • If the screen is closed or the connection drops, the output returns to 0 V.
  • Units already in use gain wireless operation by running the setup program once, in about a minute.
Connectors

Four 4 mm banana jacks

The four 4 mm banana jacks on the front of Otter I-V: blue, green, red and black from the left
BlueCurrent source 0 to 200 µA
BJT base
GreenVoltage source ±10 V
FET gate
RedVoltage source ±10 V
Resistor and diode bias / FET drain / BJT collector
BlackCurrent measurement
Resistor and diode ground / FET source / BJT emitter

Specifications

Voltage source±10 V (drain / collector, gate)
Current source0 to 200 µA (BJT base)
Current measurement±8 mA, resolution limit approx. 100 nA
Measurement routines8 — I-V, FET Transfer, FET Output, BJT Collector, I-t, Retention, Endurance, P-D
ConnectionUSB-C, Wi-Fi (tablet browser)
Power and connectorsUSB bus powered (no separate adapter), four 4 mm banana jacks
SoftwareBundled application (Windows 10 / 11) · tablet browser screen (nothing to install)
DataPC: csv / tablet: csv and a png graph. Saved automatically when the measurement ends

Considering the instruments for your lab?

We arrange demonstrations, quotations and technical support for Otter I-V and Otter I-V Expert.

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