Joulescope JS220+ Precision Energy Analyzer

Superseded by the Joulescope JS320. The JS320 is Joulescope’s current third-generation analyzer; for accredited calibration, the JS320-K001 ships with an ISO 17025:2017 NIST-traceable certificate. The JS220+ is a previous-generation variant, kept here for reference. For current orders, see the JS320.

The Joulescope JS220+ Precision Energy Analyzer is a limited-edition variant of the JS220 engineered specifically for ultra-low current measurements where standard instruments introduce too much leakage to deliver meaningful results. With +/-1 nA accuracy at the +/-20 nA range, a redesigned low-leakage analog front end built on Rogers PCB material, and ISO 17025:2017 NIST-traceable calibration from an ANAB-accredited laboratory, the JS220+ targets applications where picoamp and nanoamp accuracy is not optional — in-circuit leakage characterization, capacitor leakage measurement, energy-harvesting system profiling, and deep-sleep current validation on sub-microamp designs.

Precision Specifications

Parameter	Specification
Current Accuracy	+/-1 nA at +/-20 nA range
Analog Front End	Redesigned low-leakage topology
PCB Material	Rogers (ultra-low dielectric loss, low leakage)
Sampling Rate	2 Msps, 16-bit simultaneous ADCs
Dynamic Range	34-bit (9+ decades)
Calibration	ISO 17025:2017 NIST-traceable (ANAB accredited)
Front Panel	Custom precision panel
Current Range	+/-10 A peak (+/-3 A sustained)
Voltage Range	+/-15 V
Burden Voltage	20 mV max
Autoranging	Enwavify, 1 us switching, zero data gaps
Isolation	Electrical (sensor ports isolated from USB)
Software	Joulescope UI + Python API
Platform	Windows, macOS, Linux
Price	Contact GSAS

Why Rogers PCB Material Matters

Standard FR-4 PCB substrates have measurable surface leakage currents that become significant when characterizing devices drawing nanoamps or less. At these current levels, the instrument’s own board leakage can exceed the device under test’s actual consumption, producing measurements that reflect the instrument rather than the target. The JS220+ replaces the standard FR-4 substrate with Rogers high-frequency laminate material, which offers dramatically lower surface leakage and dielectric absorption. This materials change, combined with a redesigned analog front-end layout that minimizes parasitic leakage paths, pushes the instrument’s noise floor well below the +/-1 nA accuracy specification.

The custom front panel complements the precision analog design with optimized connector placement and shielding, reducing pickup from external electromagnetic interference that can corrupt nanoamp-level measurements. Every JS220+ unit ships with an individual ISO 17025:2017 calibration certificate from an ANAB-accredited laboratory with NIST-traceable reference standards, providing documented measurement traceability for quality systems that require it — aerospace, medical device, automotive safety, and defense programs where calibration pedigree is a regulatory requirement.

Target Applications

The JS220+ addresses measurement challenges that the standard JS220 handles well at microamp and milliamp levels but where sub-nanoamp accuracy becomes critical. In-circuit leakage characterization reveals parasitic current paths through protection diodes, ESD structures, and high-impedance nodes that drain batteries during deep sleep. Capacitor leakage measurement quantifies the self-discharge behavior of decoupling and energy-storage capacitors under actual operating conditions rather than relying on datasheet specifications. Energy-harvesting system profiling demands nanoamp-level accuracy to measure the harvester output against the load consumption and determine whether the system achieves energy neutrality. Deep-sleep validation on ultra-low-power MCUs and SoCs requires distinguishing between 100 nA and 500 nA consumption — a difference that determines whether a device achieves a 10-year battery life target or falls short.

Despite the precision enhancements, the JS220+ retains the full JS220 measurement capability: 2 Msps 16-bit simultaneous ADCs, 34-bit dynamic range, Enwavify autoranging with 1 microsecond switching, +/-10 A peak current range, and full software compatibility with the Joulescope UI application and Python API. Engineers use the same workflows, scripts, and automation pipelines they have built for the standard JS220 — the JS220+ simply delivers higher accuracy at the lowest current ranges.

Watch Joulescope in an inrush current measurement workflow

GSAS Micro Systems provides the Joulescope JS220+ Precision Energy Analyzer with pre-sales consultation on measurement fixture design for nanoamp-level accuracy, calibration documentation support for quality system integration, and post-sales applications guidance for ultra-low-power profiling workflows across India.