Michaël Chemin

Preliminary failure-mode characterization of emerging direct-lead-bonding power module. Comparison with standard wire-bonding interconnection

Abstract Direct-lead-bonding (DLB) and wire-bonding, in epoxy-moulded package, are compared in terms of functional characteristics, failure-mode and post-fault high-current capability of a dual-chip power module (PM), with respect to I 2 T and critical energy. Wire-bonding power modules have shown poor thermal behaviour, a high and unstable R CE (the chip fault residual resistance), and sometimes a fuse-effect when used in gel-filled power modules. However, DLB power modules demonstrated a very good thermal and electrical behaviour, a very low and stable R CE under high energy failure. After non-destructive defect localization thanks to Lock-In Thermography coupled to RX tomography, the authors were able to confirm the formation of a metallic bridge under wire-bondings and through the chips and solder in DLB, which explains low R CE values for this technology. The DLB interconnection appears to be a promising technology for power module. Nevertheless, the absence of wire-fuse-effect in case of extreme failure, compared to classical wire-bonding, leads the authors to rethink fail-safe and fault-tolerant strategies for critical converter.

Failure to short-circuit capability of emerging direct-lead-bonding power module. Comparison with standard interconnection. Application for dedicated fail-safe and fault-tolerant converters embedded in critical applications

The Direct-Lead-Bonding (DLB) interconnection appears to be a promising technology for power-module (PM). Nevertheless, the absence of wire-fuse-effect in case of extreme failure, compared to classical wire-bonding, leads authors to rethink fail-safe and fault-tolerant strategies for critical converter. Therefore, this paper will provide a comparative study between these two designs in terms of failure-mode and post-fault high-current capability.

Linear Voltage Stabilization System for Stop & Start vehicles

This article presents a new Linear Voltage Stabilization System (LVSS) specially meant for μ-hybrid vehicles using the “Stop & Start” function. The LVSS stabilize the battery voltage mainly during the start-up of the Internal Combustion Engine (ICE) limiting the load current using parallels MOSFETs working in linear mode [1]. The mains advantages are its small volume, avoid of EMC perturbations and specially its low price allowing Stop & Start vehicles to be more accessible to the market. The concept is validated testing the prototype in a real car.

Low cost linear current limiter for Stop-Start vehicles

This article presents a Linear Current Limiter (LCL) specially meant for μ-hybrid vehicles using the Stop-Start function. The LCL limits the current mainly during the start-up of the Internal Combustion Engine (ICE) in order to maintain the battery voltage stable. Its main advantages is the low price and the fact of avoiding EMC perturbation since it is composed of MOSFETs working in linear mode [1]. The concept is validated limiting the charging current of a capacitor by simulation and comparing with experimental results.