G.1.1. User input/output pin connections

Table G.1 shows the user input/output pin connections.

Table G.1. User I/O connections

Pin

Signal

I/O

Description

Pin 1

TestClk

-

For production test only. This pin must be left unconnected.

Pin 2

GND

-

-

Pin 3

Test1

-

For production test only. This pin must be left unconnected.

Pin 4

Test2

-

For production test only. This pin must be left unconnected.

Pin 5

Test3

-

For production test only. This pin must be left unconnected.

Pin 6

Test4

-

For production test only. This pin must be left unconnected.

Pin 7

Test5

-

For production test only. This pin must be left unconnected.

Pin 8

Reset

-

For production test only. This pin must be left unconnected.

Pin 9

+5V

Output

This is intended for use as a supply for a small amount of external logic circuitry. There is a recommended current limit of 20mA from this pin. You must remember that due to the DC-DC converter, the additional current taken from the target to supply any external logic is approximately Iout * (5V / target voltage).

Pin 10

V+HP

-

For production test only. This pin must be left unconnected.

Pin 11

Vt_out

-

For production test only. This pin must be left unconnected.

Pin 12

out-1

Output

This is a user output bit.

Pin 13

Vt_in

-

This is the voltage threshold used for input logic detection, derived from the target logic reference voltage (VTref on pin 1 of the target connector). Use this as one of the inputs to the comparator if a target logic level is being monitored.

Pin 14

out-2

Output

This is a user output bit.

Pin 15

Comp-

Input

This is connected to the inverting input of a spare LM339D comparator for use with the user-defined input/output. There is a 1MO pull-down resistor to GND on this pin.

Pin 16

in-1

Input

This is a user input bit. This uses 74ACT family input thresholds and has a 10kO pull-up to +5V.

Pin 17

Comp+

Input

This is connected to the non-inverting input of a spare LM339D comparator for use with the user-defined input/output. There is a 1MO pull-up resistor to +5V on this pin.

Pin 18

in-2

Input

This is a user input bit. This uses 74ACT family input thresholds and has a 10kO pull-up to +5V.

Pin 19

Compout

Output

This is connected to the output of a spare LM339D comparator for use with the user-defined input/output. This is an open collector output so it requires a pull-up resistor (user inputs in-1 and in-2 already have suitable pull-ups (10kO to 5V)).

Pin 20

GND

-

-

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