Parts List:

Y1

HC49U, 8 MHz crystal

D1

1N4002

L1

33 µH

P1

DB37F; parallel connector

R1

10 M

R2

2 k

RN1

10 k

JP1, JP2 HX3, 3-pin jumper

S1

SW DIP-8; 8 SPST switches

C1–3, C6, C9–11,

C19, C22

0.1 µF, 50V, monolithic ceramic

C4

68 pF, 50V, ceramic disk

C5

15 pF, 50V, ceramic disk

C7, C21

100 µF, 25V, electrolytic

C8, C12, C20 10 µF, 35V, electrolytic

C13, C16

0.01 µF, 50V, monolithic ceramic

DS011711-24

Note: The layout utilizes a split ground plane. The analog ground plane is placed under all analog signals and U5 pins 1, 34–44. The remaining signals and

pins are placed over the digital ground. The single point ground connection is at U6, pin 2, and this is connected to the motherboard pin B1.

FIGURE 16. Schematic and Parts List for the LM12(H)454/8 Evaluation/Interface

Board for XT and AT Style Computers, Order Number LM12458EVAL

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