Compensated Devices Incorporated (CDI) — legacy MIL-PRF-19500 JAN & JANS diode, Schottky, zener & rectifier sourcing
Compensated Devices, Inc. (CDI) was a Melrose, Massachusetts high-reliability diode house — JANS-certified against MIL-PRF-19500 across roughly 350 qualified part numbers — that Microsemi Corporation acquired in August 2001. The CDI brand is no longer a standalone qualified source on the DLA list; the surviving qualified line that inherited CDI's diode, rectifier, zener, and Schottky families is today listed as Microsemi Lawrence, a Microchip Company (CAGE Code 60991) on the current QML-19500. Legacy CDI-marked JAN parts (CAGE Code 55801) still show up on defense and space BOMs, which is why buyers keep searching for "CDI" specifically.
- 1974Founded
- Melrose, MAHistoric HQ
- 55801CDI CAGE
- Aug 2001Acquired
- JAN → JANSQuality Levels
- ~350 partsMIL-PRF-19500
About Compensated Devices Incorporated
Compensated Devices, Inc., universally known in the defense supply chain as CDI, was founded in 1974 and operated for 27 years as a small, specialist high-reliability diode manufacturer from a single site at 22 Corey Street, Melrose, Massachusetts 02176. The company was privately held (owned by Thomas J. Kachel at the time of sale) and reported revenue of $10.9 million for its last full year of independent operation in 2000. Despite its size, CDI held one of the wider JAN-level qualification portfolios among independent U.S. discrete-semiconductor houses — roughly 350 individual MIL-S / MIL-PRF-19500 qualified part numbers spanning switching diodes, voltage-reference diodes, low-leakage diodes, zener voltage regulators, silicon Schottky barrier diodes, current-regulator diodes, and rectifiers.
CDI's technical calling card was a proprietary high-temperature glass sealing
process for hermetic axial diodes. Microsemi Corporation, in the June 2001 press
materials announcing the acquisition, described the CDI process as
"the highest reliability manufacturing process available today" and cited it
as a primary strategic driver for the purchase. The process supported CDI's JANS
space-level certifications and its ability to hold parts to the narrow leakage, breakdown,
and long-term drift budgets that space-power and precision-analog customers required.
Compensated Devices supplied diodes and Schottky products to primes across satellite,
avionics, and missile programs and its parts show up in NASA GSFC Parts Selection List
(NPSL) records — including the well-known GSFC Advisory NA-GSFC-2002-01 on the
JANTXV1N4148UR-1 switching diode with lot date code 9918, which explicitly
identifies CDI at CAGE Code 55801 as the manufacturer ("now known as Microsemi CDI"
as of that 2002 advisory).
The 2001 Microsemi acquisition and how the line survives today
On June 12, 2001, Microsemi Corp. of Irvine, California announced concurrent agreements to acquire two Massachusetts high-reliability semiconductor houses: Compensated Devices Inc. of Melrose (for approximately $11.5 million in cash and one-year notes) and New England Semiconductor Corp. of Lawrence ($9.1 million). The Asset Purchase Agreement for CDI, filed later as a Microsemi SEC exhibit, was executed on August 15, 2001 among Compensated Devices, Inc. (seller), Thomas J. Kachel individually, Micro CDI Acquisition Corp. (a Microsemi subsidiary), and Microsemi Corporation. The transaction closed in August 2001 with a final value cited around $12 million after closing adjustments.
After closing, CDI operated for a period under the "Microsemi CDI" internal name at the Melrose site. Microsemi then consolidated its Massachusetts footprint — the neighbouring Watertown fab (originally Unitrode) closed in December 2004 — and the historic CDI operation at 22 Corey Street was ultimately rolled into the Microsemi Lawrence, Massachusetts facility at 6 Lake Street, Lawrence, MA 01841. In 2018, Microsemi Corporation was itself acquired by Microchip Technology Incorporated (Nasdaq: MCHP) for approximately $10.15 billion (closed May 29, 2018), placing the CDI-descended product families inside Microchip's aerospace and defense (HiRel) business.
Buyer takeaway. CDI parts today are qualified through the Microsemi Lawrence line. If you are searching for a JAN, JANTX, JANTXV, or JANS diode originally marked with the CDI logo and CAGE Code 55801, the equivalent current-production supply ships from Microsemi Lawrence, a Microchip Company under CAGE Code 60991, against the same MIL-PRF-19500 slash sheet.
QPL / QML-19500 status — what the DLA list actually shows
The Defense Logistics Agency (DLA) Land and Maritime real-time list of qualified sources for MIL-PRF-19500 no longer includes a standalone "Compensated Devices" entry. The surviving Microchip/Microsemi entries on the live QML-19500 are:
- Microchip Technology Inc. — Microsemi Lawrence, a Microchip Company (Lawrence, Massachusetts; HQ Chandler, AZ; CAGE Code 60991) — the direct successor line inheriting the CDI diode, rectifier, zener, and Schottky families.
- Microchip Technology Inc. — Microsemi Ireland, a Microchip Company (Ennis, County Clare, Ireland; HQ Chandler, AZ; CAGE Code 60991) — the sister QML-19500 line originally opened by Unitrode.
Two historic CAGE Codes matter for anyone auditing a legacy JAN BOM against the Microsemi/Microchip lineage:
- CAGE 55801 — Compensated Devices, Inc., 22 Corey St., Melrose MA (pre-August 2001). Widely present on legacy JAN date codes; still referenced on NASA NPSL and NEPP archives.
- CAGE 60991 — Microchip Technology Inc., Chandler, AZ — covers both current Microsemi QML-19500 plants (Lawrence and Ireland).
Legacy CAGE codes for the former Microsemi Watertown, Scottsdale, and Colorado Springs fabs, and CDI's own CAGE 55801, may still appear on old traveler paperwork. All are consolidated administratively under CAGE 60991 today, and products bearing those markings remain genuine JAN-level parts by original qualification.
MIL-PRF-19500 quality levels — what JAN, JANTX, JANTXV, and JANS actually mean
MIL-PRF-19500 is the U.S. Department of Defense performance specification for hermetically-sealed discrete semiconductor devices — diodes, rectifiers, transistors, thyristors, SCRs, and TVS devices — administered by the DLA Land and Maritime office in Columbus, Ohio (the successor to DSCC-VQ). Every CDI JAN part number carried one of the following prefixes; the same prefix structure applies today to the Microsemi Lawrence successor line:
| Prefix | Level name | What it adds vs. previous level | Typical use case |
|---|---|---|---|
| JAN | Joint Army-Navy | Baseline slash-sheet qualification with Group A/B/C conformance | Ground defense, ruggedized industrial |
| JANTX | JAN with eXtra Testing | Adds 168-hour burn-in and additional 100% electrical screening | Airborne, avionics, missile |
| JANTXV | JANTX with Visual inspection | Adds 100% pre-cap internal visual inspection | Higher-reliability avionics, tactical space |
| JANS | Joint Army-Navy-Space | Adds wafer lot acceptance, Group E conformance and full space screening | Launch vehicles, satellites, deep space |
| JANHC / JANKC | Chip / die-level | Unencapsulated die screening for downstream hybrid assembly | MIL-PRF-38534 hybrids, custom modules |
For JANTXV and JANS parts, MIL-PRF-19500 further defines eight Radiation Hardness Assurance (RHA) levels encoded as a single character (M, D, P, L, R, F, G, H) inserted into the part number, corresponding to Total Ionizing Dose (TID) guarantees from 3 krad(Si) at "M" up to 1 Mrad(Si) at "H". On top of individual part-type qualification (the older Qualified Products List, QPL), the DoD now operates a line-level certification model called the Qualified Manufacturers List (QML), which is the current framework Microsemi Lawrence (and, therefore, the CDI-descended product line) is certified against.
CDI's historic MIL-PRF-19500 product portfolio
This page intentionally lists slash-sheet families and device classes rather than individual JAN part numbers. Individual part-number availability — whether an original CDI-marked lot or an equivalent current-production part from Microsemi Lawrence — is confirmed on quote.
Silicon switching diodes
CDI was a long-standing qualified source for the workhorse 1N914 / 1N4148 switching-diode family under slash sheet /116 (JAN, JANTX, JANTXV, and unencapsulated die JANHC / JANKC). Both axial through-hole (glass DO-35 style) and hermetic MELF surface-mount variants were qualified. This family is the most likely reason a buyer today searches specifically for "CDI" against a legacy JAN drawing.
Temperature-compensated voltage-reference diodes
CDI qualified silicon voltage-reference (temperature-compensated) diodes under the /156 family (9 V low-level references) and the broader 6.4 V precision reference family later published as /452. These required tight temperature-coefficient and drift performance, well suited to CDI's high-temperature glass sealing.
Low-leakage / controlled-forward-voltage diodes
Under slash sheet /241 (silicon low-leakage controlled-forward-voltage diodes, 1N3595 device family) CDI produced JAN, JANTX, JANTXV, and JANS parts to the tighter reverse-leakage and forward-voltage windows required by precision-analog and space-instrumentation designs.
Microminiature zener voltage regulators
CDI qualified microminiature 500 mW zener voltage regulators in families that map to today's /609 slash sheet. Higher-power hermetic zener regulators (1.5 W and 5 W axial glass) also formed part of the original ~350 qualified CDI part-number list.
Silicon Schottky barrier diodes
Schottky was a named CDI specialty and one of the three product areas Microsemi cited by name in the June 2001 announcement. CDI's Schottky families — including low-barrier signal Schottkys in surface-mount MELF packages — were qualified against the /620 Schottky series and adjacent slash sheets.
Rectifier diodes
CDI produced hermetic rectifiers across standard, fast, and superfast recovery classes in glass axial packages. On the Microsemi Lawrence successor line these families sit alongside the wider Microsemi rectifier catalog and remain qualified to JAN, JANTX, JANTXV, and in many cases JANS.
Current-regulator diodes and packaging heritage
Current-regulator diodes (constant-current diodes) were a smaller but recognisable part of CDI's catalog and one reason CDI parts persist on aging analog-instrumentation and space-power designs. Across all families, CDI's hermetic glass packages centered on DO-35, DO-41, and DO-7 axial-lead bodies plus surface-mount MELF (DO-213AA / DO-213AB) with the "US" and "UR" suffixes. The proprietary high-temperature glass sealing process was the key reason the parts held up over the −65 °C to +200 °C ranges called out in the underlying slash sheets.
How Hybrid Electronics sources legacy CDI JAN parts
Hybrid Electronics Corporation is a Sanford, Florida-based independent stocking distributor and sourcing agent, founded in 1981 as Knight Electronics. We are not an authorized distributor, agent, licensee, or franchised partner of Compensated Devices, Inc., Microsemi Corporation, or Microchip Technology. Where we help defense and aerospace buyers — and where CDI most often comes up — is on legacy JAN BOMs that call out the CDI CAGE Code 55801 explicitly, or where a program has aging traveler paperwork that references CDI-marked date codes and needs either the original lot or a like-for-like current-production replacement.
Legacy CDI-marked JAN inventory
Original CDI-marked JAN, JANTX, JANTXV, and JANS diode, Schottky, zener, and rectifier lots — pre-August-2001 date codes bearing CAGE Code 55801 — sourced from OEM, CM, and long-term-storage stocks. We can typically provide date-coded traceability back through the original CDI manufacturing certifications where documentation exists.
Current-production Microsemi Lawrence equivalents
Where the exact CDI-marked lot is not available, we source the equivalent current-production part from the successor Microsemi Lawrence line (CAGE 60991) against the same MIL-PRF-19500 slash sheet and quality level. This is the standard path for buyers who need JAN, JANTX, JANTXV, or JANS supply in-tolerance to the underlying spec, regardless of manufacturer marking.
Slash-sheet cross-reference
Have a MIL-PRF-19500 slash-sheet reference (e.g. /116, /156, /241, /452, /609, /620) but no settled manufacturer part number? We can quote CDI-descended options and equivalents from other qualified suppliers on the current DLA QML-19500 list.
Frequently asked questions
Is Compensated Devices (CDI) still in business as a standalone company?
No. CDI was acquired by Microsemi Corporation in August 2001. The historic operation at 22 Corey Street in Melrose, MA (CAGE Code 55801) was consolidated into Microsemi's Lawrence, MA facility. The current DLA real-time QML-19500 list shows the surviving qualified line as Microchip Technology Inc. — Microsemi Lawrence, a Microchip Company under CAGE Code 60991.
Are legacy CDI-marked JAN parts still genuine?
Yes. JAN, JANTX, JANTXV, and JANS diodes bearing CDI markings and CAGE Code 55801 were qualified against MIL-PRF-19500 when manufactured and remain genuine JAN-level product. Equivalent current-production parts ship from the Microsemi Lawrence line under CAGE 60991 today.
When was CDI founded and what did it specialize in?
CDI was founded in 1974 in Melrose, Massachusetts and specialized in high-reliability diode, rectifier, and Schottky products. It was JANS-certified and, at the time of acquisition, was qualified against MIL-PRF-19500 for approximately 350 individual part numbers — built using a proprietary high-temperature glass sealing process.
When did Microsemi acquire Compensated Devices?
Microsemi announced the CDI acquisition on June 12, 2001 for approximately $11.5 million. The Asset Purchase Agreement between CDI, Micro CDI Acquisition Corp. (a Microsemi subsidiary), and Microsemi was executed on August 15, 2001 and the deal closed that month. Microsemi itself later became part of Microchip Technology (Nasdaq: MCHP) on May 29, 2018.
Which MIL-PRF-19500 slash sheets did CDI historically produce parts against?
CDI's ~350 qualified part numbers spanned families including /116 (1N914 / 1N4148 switching diodes), /156 and /452 (temperature-compensated voltage-reference diodes), /241 (low-leakage controlled-forward-voltage diodes), /609 (500 mW microminiature switching / zener), and Schottky barrier diode families in the /620 series, plus current-regulator diodes. Specific part-number availability is confirmed on quote.
Is Hybrid Electronics an authorized Microsemi, Microchip, or CDI distributor?
No. Hybrid Electronics is an independent stocking distributor and sourcing agent. We are not a distributor, reseller, agent, licensee, partner, or authorized service provider of Compensated Devices, Inc., Microsemi Corporation, or Microchip Technology Incorporated. All trademarks are property of their respective owners.
Trademark and affiliation notice. All company names, product names, and trademarks referenced on this page are the property of their respective owners. Hybrid Electronics Corporation is an independent stocking distributor and sourcing agent; we are not a distributor, reseller, agent, licensee, partner, or authorized service provider of Compensated Devices, Inc., Microsemi Corporation, or Microchip Technology Incorporated unless expressly stated. Component sourcing is subject to availability and inspection. Hybrid Electronics does not sell counterfeit parts and does not offer repair services. MIL-PRF-19500 and JAN quality-level designations are administered by the U.S. Defense Logistics Agency (DLA).