# Otii Arc

**Type:** Product page · **SKU:** TOL-18585 · **Brand:** [Sparkfun](https://core-electronics.com.au/brands/sparkfun-australia)
**Page:** https://core-electronics.com.au/otii-arc-49805.html ([markdown](https://core-electronics.com.au/otii-arc-49805.html.md))

## Retired product

This product is retired and no longer available for purchase. Replaced by: CE06170.

**Replacement:** https://core-electronics.com.au/catalog/product/view/sku/CE06170

## Description

We love the Otii Arc! It is a truly versatile power supply and analyzer. Coupled with powerful but easy-to-use software, it is an ideal tool to help study the power draw of your IoT project or device. It can record and display real-time currents, voltages and/or UART logs. It provides nanoamp resolution current measurements with a sample rate of up to 4000 samples per second!

Otii (pronounced like naughty) is handy in all sorts of troubleshooting situations. The Otii truly shines with any device that needs to be designed to sleep for low power and has to run 'a long time' on a battery. The Otii Arc can measure current very accurately over 8 orders of magnitude from tens of nanoamps up to 5 Amps. This means you can measure the sleep current of a board and the peak current draw all in one continuous measurement. Leave the system logging for hours then read the minimum, maximum and average current and power use straight from the oscilloscope-like recording. By linking the Otii Arc to a UART (Serial) pin and/or a GPIO pin, you can immediately see what the current draw was while the code was performing a specific task. Stop guesstimating what your runtime will be and prove it!

One of the features we really love is that you can connect a battery to the Otii Arc. The Otii Arc can then discharge the battery while recording the voltage and current profile. The Otii Arc can then *emulate* that same battery, time and time again, saving you the trouble of having to replace or recharge the battery between tests. Want to see how your board will perform when connected to a particular LiPo battery? The Otii Arc lets you do exactly that. (Battery discharge, profiling and emulation requires an additional Otii Battery Toolbox license.)

The Otii Arc has a USB interface to connect to your laptop or computer. It can use USB as its main power source and deliver up to 4.2V at 250mA to the board under test. Connect an external power supply (7.5 - 9 V) and Otii Arc can deliver up to 5.0V at 2.5A continuous, 5A peak! The accompanying software is available for Windows (7 & 10, 64-bit), macOS (High Sierra or later) and Ubuntu (18.04 or later, Intel 64-bit).

- USB Power Supply 
    - Output voltage (auto range): 0.5V - 3.75V
    - Output voltage (locked to high current range): 0.5 V - 4.2 V
    - Output voltage setting resolution: 1 mV
    - Output current: 250 mA
- External 7.5 – 9 V Power Supply 
    - Output voltage (auto range): 0.5 V - 4.55 V
    - Output voltage (locked to high current range): 0.5 V - 5.0 V
    - Output voltage setting resolution: 1 mV
    - Output current (max continuous): 2.5 A
    - Output current (max peak): 5 A
- Programmable Current Sink (requires an [Otii Battery Toolbox license](https://www.qoitech.com/buy/)) 
    - Sink current: 0 A - 2.5 A
    - Sink current resolution: 39 µA
    - Sink voltage (USB power supply): 0.85 V - 4.2 V
    - Sink voltage (external power supply): 0.85 V - 5.0 V
- Current measurement 
    - Accuracy: ±(0.1% + 50 nA)
    - Sample Rate in ±19 mA range: 4 ksps
    - Sample Rate in ±2.7 A range: 1 ksps
    - Sample Rate in ±5.0 A range: 1 ksps
    - Analog bandwidth (3 dB): 400 Hz
- Voltage measurement 
    - Total accuracy: ±(0.1% + 1.5 mV)
    - Sample Rate: 1 ksps
- UART 
    - Bitrate: 110 bps - 5.25 Mbps
- Digital I/O; GPO1, GPO2, TX 
    - VIO Expansion port operating voltage: 1.2 V - 5 V
    - VIL Low-level input voltage: VIO \* 0.2 V
    - VIH High-level input voltage: VIO \* 0.8 V
    - Imax Maximum sink/source current: 10 mA
 
 Documents - [Otii Technical Specifications](https://cdn.sparkfun.com/assets/9/7/0/1/8/Otii_Arc_TechSpec_2021.pdf)
- [How accurate is my measurement?](https://cdn.sparkfun.com/assets/5/2/2/a/e/Qoitech_How_accurate_is_my_measurement.pdf)
- [Quick start](https://www.qoitech.com/docs/quick-start/connect-otii-arc)
- [User manual](https://www.qoitech.com/docs/user-manual/otii)
- [Advanced guides](https://www.qoitech.com/docs/advanced/scripting-with-lua)
- [Tech Papers](https://www.qoitech.com/techpapers/)
- [Software and firmware download](https://www.qoitech.com/download/)
- [Additional Toolbox Software for purchase](https://www.qoitech.com/buy/)
- [FAQs](https://www.qoitech.com/faq/)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/i/m/image_3368.jpg)