UVC LED Specifications: Reading the Figures Before You Buy

Per-model figures

The catalogue states its ranges — chips across 255–340 nm, the two package families, the module forms — and the figures for a specific model are established in the enquiry exchange, for the exact band and bin being sourced.

The fields, one by one

• Peak wavelength and tolerance: the centre wavelength and tolerance recorded for the named model, confirmed per model in the enquiry exchange. A serious specification names the centre wavelength and the bin tolerance around it. The band choice itself: the wavelength guide.
• Radiant output: the output figure recorded for the named model, and the conditions it was recorded under — the drive current, whether the figure is pulsed or continuous, and the temperature at which it was taken — confirmed per model in the enquiry exchange. State the product's sustained drive point and operating temperature in the enquiry, and ask for the figure recorded against them.
• Forward voltage and drive: the forward voltage recorded for the named model, confirmed per model in the enquiry exchange. State the drive the device will actually run at in the enquiry, and ask for the figure recorded at that drive.
• Thermal figures: for packaged devices, the thermal figures recorded for the model are read against the enclosure the product will run in. Ask what thermal data is recorded for the named model.
• Lifetime basis: the lifetime figure recorded for the named model, and the duty point it is recorded at, confirmed per model in the enquiry exchange. The questions are what output the device class retains at the product's service target, and on what recorded basis — endpoint definition, test conditions and the models the figure covers.
• Binning: wavelength bins and output bins are part of what a specification names. Ask which bin records exist for the model, band by band, and have what is recorded for that model confirmed in the enquiry exchange rather than assumed.

Comparing suppliers fairly

Every figure enters the comparison with its conditions attached, or it does not enter: state the drive point, the temperature and the duty assumptions behind each figure, your own and a supplier's alike. On that basis, compare delivered dose over the product's service interval: source output at end of rated life, in the actual enclosure, at the actual duty cycle. A figure quoted without its conditions is a figure whose conditions the enquiry should establish before the design uses it.

What an enquiry for a specification states

• The job: disinfection (which medium, what dose target) or another application the design names.
• The band: the target band, named from the catalogue's named bands.
• The form: bare chip, package or finished module.
• The conditions: drive point, duty, thermal environment and service target, stated as numbers.
• The documentation: for the named model, which of the fields above are recorded and what they show — asked and confirmed in the enquiry exchange.

Worked example: two figures, one decision

Consider a static water product choosing between two bands in this catalogue. The enquiry names the per-model figures the comparison needs — how much radiant power the dose arithmetic asks for at each band, and what each device supplies at the product's sustained drive point, on what thermal basis — and asks for each figure together with the conditions it was recorded under. That is the general pattern: the specification names its conditions, and the per-model figures are established in the enquiry exchange, for the exact models being compared.

Where are the actual numbers for a model we are sourcing?

With the model, in the enquiry exchange. Name the band, form and application in your enquiry and ask which figures are recorded for that model; the figures you design against are then the ones recorded for the band and bin you are actually buying.