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5.  PC17D-2 TEST & EVALUATION BOARD
This is a 3000-mil-square multilayer board. It is drilled for many more components than would in practice be used in any one design, but affords the opportunity to try out various configurations. The use of this board, along with the guidance below, should ensure that layout issues are not a problem for first-time users. The experienced gained should be very helpful when new layouts are subsequently undertaken. Figures 8(a) and 8(b), pictures of both sides of the board, and the circuit diagram for the board are difficult to read, but if you have received this document electronically, they can be blown up since this is a pdf file. For users who receive a hard copy of these notes, we will email the pdf files for these figures to you. The plots for each layer are also available in pdf files, which will be sent to users if they request them.
 

The PC17D-2 uses the same component names as those shown in figs 2a through 2d. There are some minor differences that are listed below.
  1. On the PC board there is a space for an input resistor, Rin, between the input connector and pin 35. This is for users who are using a pulse generator, rather than a detector to test the chip. Detector users should bridge this connection.
  2. RLIN is tapped from pin 6 rather than pin 34 to provide linear extension.
  3. A1 out is connected to the A2 input directly on the board. Similarly A2 out is connected to the A3 input on the board. Users who wish to AC couple, or who wish to insert a limiter between A1 and A2 should not connect pin 32 and/or pin 28 to the board. They can then make the desired connection through a capacitor, or limiter, directly to the pin, since neither pin 32 nor pin 28 requires any other connection.
  4. RT0X is not shown in fig 2. Read the section on temperature compensation to learn how to use the temp compensation on this board.
  5. R8 and C8 shown in figure 2 are not on the board as they were found to be unnecessary.
  6. There is provision for an extra recovery net for A2 on the board. The components are labeled RV4 and CV4.
  7. There is an option to take RT3 to VCC or VEE. See the section on how to use the temperature compensation.
  8. R12 and C12 are not on the board. They are not necessary.
  9. An RC net RS3 and CS3 is provided to speed up A3. This has been found to be more effective than C13.
  10. There is no provision for R22. It is rarely useful.

Note: for several of the offset corrections, places are provided to insert pots. In some cases jumpers are necessary. Once the value has been determined, the jumper should be removed and a fixed resistor should be put in place on the other side of the jumper. This avoids long exposed lines.
After using the PC17D-2 for some time, we have found that some components not shown in fig 2 are necessary under certain conditions. These are listed below.
  1. When running the board with rail voltages greater then +/-6V, it is necessary to place a capacitor of 3pf to 5pf across R21. There is no provision for this, but it is easy to add; simply solder the cap across R21.
  2. There is no provision for a limiter between A1 and A2. If you wish to use a limiter please see the section about A2 on page 24 where the procedure for AC coupling is described.
 
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February 20, 2008
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