EVAL-ADM1023 Datasheet, PDF (4/12 Pages) Analog Devices – Evaluation Board for Microprocessor System Temperature Monitor

EVAL-ADM1023
Preliminary Technical Data
CONNECTORS, SWITCHES AND INDICATORS
The function of the various connectors, links and
indicators on the evaluation board are explained below.
TEST CONNECTOR
Test Connector J1 allows an external diode to be
connected between the D+ and D- terminals of the
ADM1023
TABLE 2. ADM1023 DEVICE ADDRESSES
Address Pins
ADD1 (LK2) ADD0 (LK3)
0(LK2 Closed) 0(LK3 Closed)
0(LK Closed) NC(LK Open)
NC(LK2 Open) 0(LK3 Closed)
NC(LK2 Open) NC(LK3 Open)
Device Address
Binary
Hex
0011000(0) 0
0011001(0) 32
0101001(0) 52
0101010(0) 54
CENTRONICS INTERFACE CABLE
The evaluation board and the personal computer may be
connected via the printer parallel port using the contronics ^{STANDBY INPUT LK4}
cable provided. The connections to J2 are as follows.
The ADM1023 has an active low standby input, pin 15
Y _{REMOTE SENSOR SELECT LK1}
R ^{The function of this jumper is to allow the user to choose}
between measuring tempertature using the on-board
A _{remote sensor and an external one connected between the}
IN ^{D+ and D- terminals of J1. When the middle pin is linked}
L _{to B the on-board sensor is used and when the middle pin}
IM ^{A is linked to A the off-board sensor is used.}
controlled by LK4 on the evaluation board. This is a logic
input that enables selection between normal operation
(high) and standby operation (low). Without the shorting
link the pin is high (normal mode). With the shorting link
the pin is low (standby mode). This input performs the
same function as bit 7 of the status register
REL ^{NIC TABLE 1. ADM1023 SENSOR SELECTION}
P ^H LK1 Position
EC ^{TA A}
T _{DA B}
Sensor Selected
External Sensor
On-baord NPN Sensor
SERIAL BUS ADDRESS SELECT
LK2 and LK3 are used to set the two LSB’s of the
ADM1023’s serial bus address, ADD0 and ADD1. These
pins are tri-state and can be grounded, left unconnected or
tied to V_DD. This means a total of nine addresses are
possible. However for simplicity on the evaluation board a
jumper is used to allow each pin two states ( 4 Addresses).
The pin is floating when the shorting link is not on the
board. The pin is grounded when the shorting link is
placed on the board. It should be noted that ADD0 and
ADD1 are only read at power up. If LK2 or LK3 are
changed while the ADM1023 is on, the change of address
will not be effective until the device has been powered off
and then on again.
As the serial bus address is seven bits, when storing it as
an 8-bit word it must be left or right justified, with either
the MSB or the LSB of the 8-bit word as zero. The
ADM1023 evaluation software stores the 7-bit serial bus
address as left justified and makes the LSB zero. Table 2
shows the four possible addresses possible on the
evaluation board
–4–
REV. A