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3.5 JP7
The 20 pin header JP7 allows access to VID0-VID4, RESET#, INT# and THERM# input and outputs pins
of the LM87. The board comes shipped with shorting bars installed across the following pins:
Pins 9 and 10
as shown in FIGURE 1.
Table 3 JP7 Description
Pin Number
Description
1
Pin 1 of LM87, ADD_HI (Connects ADD to Vcc through a 3.9k resistor)**
2
Vcc
3
Pin 1 of LM87, ADD_LO (Connects ADD to GND through a 3.9k resistor)**
4
GND
5
Pin 2 of LM87, THERM#In (Allows THERM# to be jumpered to GND for input use)
6
GND
7
Pin 2 of LM87, THERM#Out (Allows THERM# to be monitored by software)
8
LED D5 cathode and Pin 11 of Connector P1 DB25 (parallel printer port)
9
Pin 10 of LM87, INT# (Allows INT# to be monitored by software)
10
LED D5 cathode and Pin 11 of Connector P1 DB25 (parallel printer port)
11
Pin 12 of LM87, RESET#
12
R5 and D7 (Allows PC to apply a Reset Input to the LM87 RESET#)
13
Pin 24 of LM87, VID0
14
GND
15
Pin 23 of LM87, VID1
16
GND
17
Pin 22 of LM87, VID2
18
GND
19
Pin 21 of LM87, VID3
20
GND
21
Pin 20 of LM87, VID4
22
GND
**Caution: Do NOT install jumpers for both ADD_HI and ADD_LO at the same time. This will short Vcc
to GND and can cause damage to the on board voltage regulator.
3.6
JP2 and JP4
In addition to these headers, JP2 has been provided to permit measurement of the LM87 supply current.
This connector is not installed in the circuit board. To measure the LM87 supply current, cut the printed
circuit board trace between pin 1 and pin 2 of JP2. Then install a two-pin header and measure the current
that flows between the two pins. A shorting jack can be used to operate the LM87 normally when you are
finished measuring. JP4 has been providing for monitoring the NTEST_OUT signal when evaluating the
NAND tree test mode of the LM87.