7.  SOME COMPONENT VALUES FOR THE PC17D-2

The next page is a sample output picture of an L-17D running on a PC-17D test board. The input came from a pulser through 50 ohms connected to the negative input of A1. The rail voltages were ± 6V. The picture was taken with a 7 pF x10 probe. The input pulse was the maximum that could be used without limiting A1 so that the figure shows the recovery time of the chip from full power.

The values of components used for this unit are listed below. (Note that resistors used to correct for offsets will vary from part to part, and therefore these values may not be appropriate for each specific case.)**

A1.
R1  51 Ω (not applicable if using a detector)
C1  10 nF
R2  360 Ω
R3  820 Ω*
C3  3.3 pF*
A1 also has a 51Ω cable attached. It is also run without any comp cap (C4)

A2.
C7  2.2 pF

A3.
None

Output Amp.
C14  68pF
R23  2 kΩ
C16  1 pF
C15  3.9 pF
R26  100 Ω (Pictures were taken with a 7 pF x10 probe)

Recovery nets were used but they were used largely to compensate for the pulser tail and the values used could be misleading so we have chosen not to list them. There was no limiter used between A1 and A2. Use of a limiter could improve the fall time further as the falling edge still shows some indication of a shoulder resulting from the recovery of A2.

*These values depend on your input configuration. See text page 24. With a pulser and 50Ω input resistor, we used either C2=1pf, or the R3-C3 combination.
** Approximate values for R4 (A1 offset): 91k to VCC
R10 (A2 offset): 300k to VEE
R15 (A3 offset): 500k to ground
R20 and R21 30k to VCC