Known-Brand EOL High Voltage Diode Replacements — Fuji, Origin, Philips, Semtech

Status, stated honestly

Not every "obsolete" label means the same thing. A written abolishment notice, a line retired with its market, and a part dropped by distribution are three different risks for a buyer. We keep them separate.

Brand index

Fuji Electric ESJC — the only written death certificate

Fuji Electric issued an abolishment notice on 4 November 2005 for the ESJC series: ESJC03, 04, 07, 13, 15, 16, 30, 32, 34, 35 and 37 types. Final order receipt was the end of January 2006, final production the end of March 2006. The stated reasons were order volume too small for stable production and ageing equipment.

The parts were built for microwave oven high voltage supplies and remain in service across installed appliances. An official notice still exists on Fuji's own site, which is why this is the one line on the page we can call discontinued without qualification.

Fuji Electric ESJA — retired with the CRT

ESJA was the flyback and voltage multiplier diode for CRT televisions and monitors. The ESJA09 group was marked obsolete in March 2007 as flat panels took the display market. The series was not abolished by notice; it simply had no market left.

Origin Electric MD — the medical X-ray line

Origin Electric discontinued the MD8CP5 (8 kV / 500 mA / 50 ns) in spring 2023 and moved production toward higher voltage silicon stacks. The part traces its lineage to Sanken's UX-FOB and sits inside medical X-ray generators and DR systems, including Shimadzu equipment.

Related MD numbers still in service include MD4CN6, MD4CH5, MD4CU4, MD6CH4, MD6DH7, MD15EP06 and MD15FP3. HVC publishes a dedicated MD8CP5 replacement note.

Philips / NXP BY84xx — oil and SF6 rectification

BY8404 through BY8424 covered 5 kV to 30 kV at 3 to 20 mA in the SOD61 axial outline, used in oil-immersed and gas-insulated rectifier stacks. Philips Semiconductors became NXP and left the category; exact replacements have to respect the insulation medium, not just the electrical rating.

Semtech SCH and Toshiba CL01 — middle state

Both have stepped back from primary distribution while stock still circulates through brokers. Treat them as a lead-time risk: qualify a second source before the next build rather than waiting for a last-time buy. CL01-12 is widely second-sourced and behaves like a commodity; SCH remains a slow recovery part that needs the exact rating quoted.

Ce que nous ne prétendons pas

Sanken UX-F, HVCA, EDI and VMI are still in production. They appear in our cross-reference tables because customers ask for them by number, not because anyone discontinued them. Writing "discontinued" on a live part is how a supplier loses a customer in one email.

Sanken's active UX-F range is handled on a separate page as a deuxième source.

Model-by-model cross reference

97 of 121 discontinued numbers on this page carry a mapped HVC equivalent. Where no HVC part sits inside the original envelope, the row reads "Quote on application" instead of guessing a number.

Same equipment, other high voltage parts

An assembly that still runs one of these diodes usually carries high voltage ceramic capacitors and a rectifier stack on the same chassis. We supply those too, so a spare-parts list does not have to be split across three vendors.

HV ceramic disc capacitors, 2KV–50KV ·Rectifier stacks, 267 standard parts ·Résistances haute tension