Joulescope JS220

Now succeeded by the Joulescope JS320. The JS320 is Joulescope’s third-generation precision DC energy analyzer, with improved low-current accuracy (24-bit measurement path, Enwavify v2). The JS220 is currently shown out of stock on the Joulescope store. For current orders, see the JS320.

The Joulescope JS220 is a precision DC energy analyzer purpose-built for embedded systems power profiling. With 0.5 nA resolution across a 34-bit dynamic range — from nanoamps in deep sleep to +/-10 A peak current bursts during wireless transmission — it captures power behavior that conventional multimeters and oscilloscope-based shunt measurements cannot see. Simultaneous 16-bit ADCs sampling at 2 Msps measure current, voltage, power, energy, and charge concurrently, with 300 kHz bandwidth that resolves fast transients like ISR wake-ups, inrush currents, and regulator switching artifacts.

Measurement Ranges

Parameter	Range	Resolution
Current	+/-10 A peak (+/-3 A sustained)	0.5 nA
Voltage	+/-15 V	2 uV
Power	Computed real-time	Derived from I x V
Energy	Integrated over capture	Joules and Ah
Bandwidth	300 kHz	2 Msps 16-bit ADCs
Autoranging	Enwavify, 1 us switching	Zero data gaps
Burden Voltage	20 mV max	Minimal target perturbation
Isolation	Electrical	Prevents ground loops
Capture Duration	Unlimited	Streaming to disk
Dynamic Range	34-bit (9+ decades)	nA to 10 A

The proprietary Enwavify autoranging technology switches ranges in 1 microsecond with zero gaps in the data stream, eliminating the dead zones that plague traditional autoranging instruments. A low 20 mV burden voltage ensures the target device operates within normal parameters — critical for accurate low-power profiling where even small voltage drops alter firmware behavior. The JS220 is electrically isolated, preventing ground loops between the instrument and device under test. Unlimited data capture duration with the Joulescope UI (Windows, macOS, Linux) enables multi-day battery life validation, while the Python API supports scripted automation for production test, regression profiling, and CI-integrated power budgeting. Swappable front panels and customizable configurations adapt the instrument to bench, rack-mount, and automated test environments.

The JS220 addresses the fundamental challenge of modern embedded power profiling: the dynamic range between deep-sleep nanoamp currents and peak milliamp-to-amp active bursts spans nine or more decades, far exceeding the capability of conventional instruments. By capturing this entire range simultaneously and continuously, the JS220 enables engineers to measure actual battery life under real firmware behavior, identify unexpected wake-ups that drain batteries, and quantify the energy cost of individual firmware operations — from BLE advertisement to sensor acquisition to flash write.

Watch the Joulescope JS220 demo

GSAS Micro Systems provides the JS220 with applications guidance for power profiling workflows, fixture integration, and Python API automation for teams building power-aware IoT, wearable, and battery-operated products across Bengaluru, Hyderabad, Chennai, Pune, Mumbai, and Delhi NCR.