Every H & M-Grade Maxi, Mini, and Micro as well as MI Family modules undergoes extensive post-production environmental stress screening (ESS) before shipment to verify compliance with Vicor's high quality and performance standards and to eliminate early life failures. To ensure the most effective routine for precipitating module failures, we continually evaluate our ESS program and make appropriate changes as new data become available or as product improvements occur. After burn-in and temperature cycling, each module undergoes final electrical testing over the specified temperature range. The program is outlined below.
|MI Family Module Screening||Maxi, Mini & Micro Module Screening|
|Operating Temperature||MI-200||MI-200||-40 to +100°C||-55 to +100°C|
|-55 to +85°C||-55 to +85°C|
|-40 to +100°C||40 to +100°C|
|Storage Temperature||MI-200||MI-200||-55 to +120°C||-65 to +125°C|
|-55 to +100°C||-65 to +100°C|
|-55 to +125°C||-65 to +125°C|
|Temperature Cycling||12 cycles||12 cycles||12 cycles||12 cycles|
|17°C per minute nominal rate of change, dwell time until product stabilization||-65 to +100°C||-65 to +100°C||-65 to +100°C||-65 to +100°C|
|Ambient Test @ 25°C||Yes||Yes||Yes||Yes|
|Power Cycling Burn-In||12 hours||96 hours||12 hours||24 hours|
||29 cycles||213 cycles||29 cycles||58 cycles|
|Functional & Parametric ATE TestsLow and high temperature||-40 to +85°C||-55 to +85°C||-40 to +100°C||-55 to +100°C|
AC or equivalent DC
Before packing into ESD containers
Because operating temperature is one of the most important factors in determining overall module reliability, it is imperative that the user's system design allow for efficient heat transfer from the baseplate to system ambient. Since temperature and failure rate are exponentially related, just a 10°C decrease in baseplate temperature can have a dramatic increase in MTBF. Due to patented zero-voltage/zero-current switching topology, Vicor converters are highly efficient compared to those with more traditional topologies. High efficiency translates into both smaller size and lower temperature rises. To minimize thermal impedance, all major power dissipating components are mounted directly to the baseplate.
Below are representative calculated MTBF values based on MIL-HDBK-217F. If you require information about a specific model, contact Vicor with the model number, expected baseplate temperature, and operating environment to obtain an individually prepared report.
|MTBF in 1000 Hours|
|Part Number||Baseplate Temperature||G.B.||G.F.||A.I.C.||N.S.|
Fully encapsulated, Vicor Maxi, Mini, Micro, and MI family modules utilize a proprietary spin fill process that assures complete, void free encapsulation making them suitable for the harshest environments. In addition to providing mechanical rigidity, the encapsulant is thermally conductive to eliminate hot spots and aid in heat transfer to the baseplate. Modules are available with temperatures down to -55°C operating and -65°C storage.
To verify the suitability of Vicor's H & M-Grade Maxi, Mini, and Micro as well as MI Family modules for harsh environments, these products have been subjected to the environmental testing requirements of MIL-STD-810, MIL-S-901 and MIL-STD-202. These tests, listed below, are performed at an independent laboratory. Additional environmental tests can be done upon individual customer request.
|Environment||MI Family Module||Maxi, Mini & Micro Module|