Joulescope JS320

The Joulescope JS320 is the third-generation Joulescope precision DC energy analyzer, succeeding the JS110 and JS220 with a redesigned measurement path focused on improved low-current accuracy. It measures current from nanoamps to amps while simultaneously measuring voltage, power, energy, and charge, making it especially well-suited to modern low-power embedded systems: BLE devices, sensors, remote controls, energy-harvesting products, and battery-powered IoT designs.

Measurement Specifications

Parameter	Specification
Current	+/-3 A continuous, 10 A pulses
Current resolution	0.1 nA
ADC	24-bit, 18 effective number of bits (ENOB)
Sample rate	1 Msps, simultaneous current and voltage
Dynamic range	36-bit (64-bit internal digital path)
Voltage	+/-15 V
Bandwidth	200 kHz
Autoranging	Enwavify v2, 1 us switching
Isolation	Sensor ports electrically isolated from USB
Platforms	Windows, macOS, Linux + Python API
Variants	JS320-K000 (factory calibration), JS320-K001 (ISO 17025 calibration)

The JS320 keeps the simultaneous current, voltage, power, energy, and charge measurement that defines the Joulescope, and pairs it with Enwavify v2 autoranging. Where the previous generation held to a fixed range during transitions, Enwavify v2 measures using any current range during range changes, reducing accumulated error for low-current systems while preserving the 1 microsecond switching with no gaps in the data stream. The sensor ports are electrically isolated from USB, and the instrument accepts Joulescope’s interchangeable front panels, including the existing JS220 front panels.

What is new in the JS320

According to Joulescope, the JS320 improves on the JS220 in several measured ways:

• Offset stability: nanoamp-level stability over a day, with significantly improved offset behavior across all current ranges, benefiting low-power measurements.
• ADC: upgraded from a 16-bit ADC (15 ENOB) to a 24-bit ADC (18 ENOB); the internal digital path expands from 36-bit to 64-bit, reducing quantization from approximately 0.9 nA to 22 fA.
• Enwavify v2: measurement using any current range during current-range changes, rather than being fixed to the 10 A range during transitions.
• Analog filtering: the 6th-order Butterworth filter is replaced with a 2nd-order maximally flat Bessel filter for greatly reduced step-response overshoot and a cleaner time-domain response.
• Clock accuracy: improved by 5x for better multi-instrument synchronization.
• USB: operating range extends down to 4.5 V (versus the JS220’s 4.75 V minimum).

Calibration options: JS320-K000 and JS320-K001

The JS320 is offered in two variants, identical instruments that differ only in calibration:

• JS320-K000: factory calibration, supplied with a factory calibration certificate. The standard choice for engineering and product-development benches.
• JS320-K001: ISO 17025:2017 NIST-traceable calibration, for teams that need accredited, traceable calibration to satisfy a quality system or audit.

Both carry the same measurement performance. GSAS can also arrange periodic recalibration and validation for JS320 units already in the field through a partner lab in India. Talk to GSAS for India pricing and to choose the right calibration option for your programme.

The JS320 (ordering SKUs JS320-K000 and JS320-K001) is Joulescope’s current third-generation instrument, succeeding the JS220.

GSAS Micro Systems supplies the Joulescope JS320 in India with applications guidance for power-profiling workflows, fixture integration, and Python API automation, supporting teams building power-aware IoT, wearable, and battery-operated products across Bengaluru, Hyderabad, Chennai, Pune, Mumbai, and Delhi NCR.