Biomedical Engineering Reference
In-Depth Information
180
Routing-oblivious synthesis
Routing-aware synthesis
160
140
120
100
80
60
320
340
360
380
400
420
440
Time Limit (s)
Figure 2.8
Feasibility frontier and feasible design region for [15] and the routing-aware synthesis method.
As shown in Figure 2.8, routing-aware synthesis leads to a lower feasibility
frontier and a larger feasible design region. For tight time limits, for example,
320 s, the routing-aware method achieves a routable synthesis result with less
than 140 electrodes, while the routing-oblivious method fails when the area
limit is lower than 170 electrodes. On the other hand, for a fixed array size,
for example, 110 electrodes, routing-aware synthesis leads to a much lower
assay completion time (less than 360 s) than the routing-oblivious method
(between 380 and 400 s). The improvement becomes more significant when
routing time is considered and added to the assay completion time. In addi-
tion to assay-time reduction, routing-aware synthesis allows us to reduce chip
area, and thereby the product cost for disposable and reusable biochips.
Next, we carry out postsynthesis routing for all the routable synthesis
results corresponding to the feasible layouts and use schedule relaxation as
defined in Section 2.2 to derive the adjusted completion time. We add the
droplet transportation time to the assay completion time in each case. The
results are shown in Figure 2.9. These results show that in addition to provid-
ing a greater range of feasible design points, routing-aware synthesis leads to
lower assay completion times.
2.4.2 results for Postsynthesis Defect Tolerance
Next, we investigate defect tolerance using the previous example. Assume that
the preceding biochip has been fabricated. Suppose that due to particle con-
tamination, three cells in the 10 × 10 microfluidic array in Figure 2.6 are ren-
dered defective, as shown in Figure 2.10a. In order to ensure that the protein
assay can still be carried out on this biochip, we need to bypass these faulty
cells during assay operation. Moreover, due to defective cells, some nonrecon-
figurable resources may no longer be available. In this example, we assume
Search WWH ::




Custom Search