Electrical Requirements

4.Calibration – Cascade Calibration Substrates or equivalent.

5.Measurement objects – packages, sockets, motherboards.

Measurement Steps:

•Equipment Setup

R

Cables should be connected to the network analyzer and to the probes using the appropriate torque wrench to ensure consistent data collection every time the measurement is performed.

•Set VNA

Bandwidth = 30 0KHz – 3 GHz with 801 points.

Averaging Factor = 16.

•Perform Open/Short/Load calibration:

Calibration should be performed at the start of any measurement session.

Create Calibration Kit if necessary for 1st time.

Do not perform port extension after calibration.

•Check to ensure calibration successfully performed.

•Measure the inductance of configuration 4 of the package mounted on the socket, which is mounted to the motherboard fixture (Figure 4-5):

Call this Lsocket assembly .

Export data into MDS/ADS or (capture data at frequency specified in Item 6 of Table 4-1).

•Measure the inductance of configuration 4 of the package mounted on the socket, which is mounted to the motherboard fixture (Figure 4-5). Call this Lsandwich :

Measure 30 units.

The package for 30 units must be chosen from different lots. Use 5 different lots, 6 units from each lot.

Export data into MDS/ADS or (capture data at frequency specified in Item 6 of Table 4-1).

Calculate Lsandwich .

For each socket unit, calculate

Lsocket = Lsocket assembly − Lsandwich

It means Lsandwich will be subtracted from each Lsocket assembly and the result will be compared with spec value for each individual socket unit.

4.3.2Correlation of Measurement and Model Data Inductance

To correlate the measurement and model data for loop inductance, one unit of measured socket assembly (socket and shorted test fixture) and one unit of measured sandwich (shorted test fixture) will be chosen for cross-sectioning. Both units will be modeled based on data from cross-sectioning using Ansoft 3D*. The sandwich inductance will be subtracted from socket assembly inductance for both measured and modeled data. This procedure results in loop inductance for socket pin + interposer pin. This final result can be compared with the loop inductance from the supplier model

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mPGA604 Socket Design Guidelines