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For ESD test (HBM)' F7 r3 S0 q: ^; m) [) j+ A2 ^# N
The following are the test combination:9 ^& k- Y* [" B* H
1. Power to Power
% h3 ?* }$ k* f: \. f* E8 l2 U2. Power to Ground
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4. Io to Ground' O. O1 N( Q) ]1 d$ P+ r, U! T
5. IO to IO3 v$ ^) q# c4 @9 k
(different power domain need to be treated as different power. For ground usually you can treat as one group_silicon use substrate as common ground. But if you measure two different ground pin/ball > 2ohms. It should be seperated as 2 grond.)4 |, L1 T+ T2 {# Z; L
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the total zap time fomula will be~ 2(+/- polarity) X (IO#X(P#+G#)+IO#+P#X(P#-1)X(P#-2)X...X1+P#XG)3 B4 }( k/ H; b6 S# _/ P
For example: You have IO1/IO2/IO3/P1/P2/G1: W. `: V g- P2 y5 U6 j$ l
2x((3X(2+1)+3+2X1+2X1)=25(multiple the zap interval)% @! h1 {* G( _7 q1 s
So for high pin count it will take a lot of time. But it won't take more than a week(for one chip). . `6 ~. o/ W3 w4 R" j/ l$ a
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For your reference. |
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