Otii Arc Pro

Hardware overview

The front side of the Otii Arc Pro has the main connectors, additional ports to extend measurement capabilities, plus a status LED.

Arc front

The back side of the Otii Arc Pro has the host Micro-USB connector and an input socket to power up the unit with an external DC adapter when required.

Arc back

Main connections

The Otii Arc Pro has the voltage(+) and voltage(-) binding post (red and black connectors located on the right side of the instrument), which are used to source the DUT but also to measure the current, voltage, and power of the device. The DUT can be connected through its battery connectors or DC input; refer to the connection diagram below for better understanding.

Arc connected to DUT

To power up the Otii Arc Pro and enable communication with the host computer, connect the unit to your computer using the provided USB micro B to USB A cable.

Arc connected to a computer

Check out the Wiring up page to explore all possible connection configurations between the Otii Arc Pro and your DUT.

Expansion Port

The expansion port on the front of the Otii Arc Pro is designed to enhance the hardware's functionality, allowing users to measure additional voltages and currents or trigger external events. These additional pins feature multi-input and multi-output for analog and digital signals, serial communication, and additional power and ground points. Below is a general overview of the additional pins available:

ConnectorDescriptionMaximum rating
+5V5 V output500 mA
DGNDDigital ground (return current)
RXUART RX / Digital Input (Exclusively under Scripting)0 V to 5.5 V
TXUART TX / Digital Output (Exclusively under Scripting)0 V to 5.5 V
GPI1Digital input 10 V to 5.5 V
GPI2Digital input 20 V to 5.5 V
GPO1Digital Output 10 V to 5.5 V
GPO2Digital Output 20 V to 5.5 V
DGNDDigital ground (return current)
AGNDAnalog ground (return current) / Analog measurements
ADC+Differential input for current measurement. It also measures single ended voltage with respect to AGND0 V to 5.5 V
ADC-Input for current measurement0 V to 5.5 V
SENSE+Analog input with the AGND as reference/return0 V to 5.5 V
SENSE-Analog input with the AGND as reference/return0 V to 5.5 V

Status LED

The table below explains the Otii Arc Pro's status LED behaviors and their meanings to help you quickly identify the device's state.

LED behaviorOtii Arc Pro Status
Flashing greenOtii Arc Pro is active
Solid greenRelay closed, sinking/sourcing power

Arc Tech spec

General

Operating environmentMinTypicalMax
Temperature10°C / 50°F30°C / 86°F
Humidity30 %60 %
USB power supply1MinTypicalMax
Output voltage (auto range)0.5 V3.75 V
Output voltage (locked to high current range)0.5 V4.2 V
Output voltage setting resolution1 mV
Output current, max continuous 3up to 1 A 12.4 A
Output current, max peak 3up to 1 A 15 A
External 7.5 v - 9 v power supply2MinTypicalMax
Output voltage (auto range)0.5 V4.55 V
Output voltage (locked to high current range)0.5 V5.0 V
Output voltage setting resolution1 mV
Output current, max continuous 32.4 A
Output current, max peak 35 A
Programmable current sink (requires an Otii Toolbox)MinTypicalMax
Sink current0 A2.5 A
Sink current, setting resolution39 µA
Sink voltage, USB power supply0.85 V 44.2 V
Sink voltage, external power supply0.85 V 45.0 V
Current measurementMinTypicalMax
Accuracy±(0.1 % + 50 nA)5
Sample Rate in ±19 mA range4 ksps
Sample Rate in ±2.7A range1 ksps
Sample Rate in ±5.0 A range1 ksps
Analog bandwidth (3 dB)400 Hz
Voltage measurementMinTypicalMax
Total accuracy±(0.1 % + 1.5 mV)
Sample rate1 ksps

Expansion port

UARTMinTypicalMax
Bitrate110 bps5.25 Mbps
Digital I/O6MinTypicalMax
Digital IO operating voltage1.2 VVio 75 V 8
VIL Low-level input voltageVio * 0.2 V
VIH High-level input voltageVio * 0.8 V
Imax, Max sink/source current (total for GPIOs)-10 mA10 mA
Differential ADC, pins ADC- and ADC+9MinTypicalMax
Voltage input0 V5 V
Shunt voltage range-81.9175 mV81.2 mV
Resolution2.5 µV
Accuracy±(0.1 % + 10 µV)
Input impedance220 kΩ
Single ended ADC, pins ADC- and ADC+9MinTypicalMax
Voltage input0 V5 V
Resolution1.25 mV
Accuracy±(0.1 % + 7.5 mV)
Input impedance830 kΩ
SENSE, pins SENSE- and SENSE+MinTypicalMax
Voltage input0 V5 V
Resolution1.5 mV
Accuracy1 %
Input impedance1 MΩ
Expansion port power supplyMinTypicalMax
Output voltage5 V 10
Output current500 mA

USB and DC jack

DC jackMinTypicalMax
Input voltage7 V9 V
Input current5 A
USBMinTypicalMax
VBUS voltage4.75 V5.25 V
VBUS current3 A