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7.0 Computer Modelling Parameters

7.1 Device Dissipation Calculations

Fast Recovery Diode Types M0863LC260 to M0863LC360

I AV = − Vo +

Vo + 4 ⋅ ff 2 ⋅ rs ⋅WAV

2 ⋅ ff 2 ⋅ rs

Where VT0 =1.308V, rT = 0.538mΩ

ff = form factor (normally unity for fast diode applications)

WAV

=

∆T

Rth

∆T = Tj(MAX ) − TK

7.2 Calculation of VF using ABCD Coefficients

The forward characteristic IF Vs VF, on page 6 is represented in two ways;

(i) the well established VT0 and rT tangent used for rating purposes and

(ii) a set of constants A, B, C, and D forming the coefficients of the representative equation for VF in

terms of IF given below:

VF = A + B ⋅ ln(IF ) + C ⋅ I F + D ⋅ IF

The constants, derived by curve fitting software, are given in this report for hot characteristics. The

resulting values for VF agree with the true device characteristic over a current range, which is limited to

that plotted.

25°C Coefficients 125°C Coefficients

A 1.365043

0.039917902

B -0.1023829

0.2045307

C 9.1211×10-5

D 0.0343427

4.10581×10-4

9.62577×10-5

8.0 Frequency Ratings

The curves illustrated in figures 8 to 16 are for guidance only and are superseded by the maximum ratings

shown on page 1.

9.0 Square wave ratings

These ratings are given for load component rate of rise of forward current of 100 and 500 A/µs.

10.0 Duty cycle lines

The 100% duty cycle is represented on all the ratings by a straight line. Other duties can be included as

parallel to the first.

Data Sheet. Types M0863LC260 to M0863LC360 Issue 1

Page 5 of 11

November, 2003