Page 22 - Chip Scale Review_November-December_2023-digital

Table 1: Key design criteria.
for optimized drive capability. Several external bill of
materials (BOM) components are reduced or removed though
features integrated into the gate drivers, thereby providing
system-level board space and cost savings. This new
GDIC incorporates programmable control for protections,
monitoring, and diagnostic features such as <1µs short-circuit
detection, temperature, over-voltage/over-current protection
and power device aging detection, which enable optimized
performance and predictive maintenance of the traction
inverter and power devices.

Table 2: Applicable standards and description.
Design objectives
Key performance, reliability, isolation and manufacturing
criteria necessary to satisfy the application requirements are
summarized in Table 1. Communication performance refers
to data transfer between voltage domains. In fact, galvanic
isolation demands a multitude of requirements driven by
a variety of industry standards, summarized in Table 2
(references in table). Component reliability qualification
followed the norms of AEC Q100 and Q006.
Package design
To achieve galvanic isolation, the package is divided into
LV and HV regions that could electrically connect to their
respective system domains but remain insulated from each
other by appropriate isolation barriers. The design required
isolation strategies external to the package (outside the mold
body) and internal to the package (inside the mold body).
The standards in Table 2 define a variety of metrics to
ensure packages and systems can meet their stated isolation
specifications. Table 3 summarizes exemplary parameters
from these standards.
External isolation is achieved by selecting a package
outline to meet the first two parameters in Table 3: creepage
and clearance. A 32-lead 7.5mm x 11.0mm wide-body SOIC
package is ideal. With leads on only two sides, leads 1-16
are connected to the LV domain and leads 17-32 to the HV
domain. Figure 2 illustrates that the creepage path around

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