ADM1021ARQZ ON Semiconductor, ADM1021ARQZ Datasheet - Page 14

• Manufacturer Part Number: ADM1021ARQZ
• Description: IC SENSOR TEMP DUAL3/5.5V 16QSOP
• Manufacturer: ON Semiconductor

Specifications of ADM1021ARQZ

• Function: Temp Monitoring System (Sensor)
• Topology: ADC, Comparator, Multiplexer, Register Bank
• Sensor Type: External & Internal
• Sensing Temperature: 0°C ~ 100°C, External Sensor
• Output Type: SMBus™
• Output Alarm: Yes
• Output Fan: No
• Voltage - Supply: 3 V ~ 5.5 V
• Operating Temperature: 0°C ~ 100°C
• Mounting Type: Surface Mount
• Package / Case: 16-QSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

current sources, excessive cable and/or filter capacitance
can affect the measurement. When using long cables, the
filter capacitor can be reduced or removed.
resistance of 1 W introduces about 1°C error.
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
*The “Z’’ suffix indicates Pb−Free part.
ORDERING INFORMATION
Specifications Brochure, BRD8011/D.
ADM1021AARQZ
ADM1021AARQZ−R
ADM1021AARQZ−R7
Because the measurement technique uses switched
Cable resistance can also introduce errors. A series
5. Place a 0.1 mF bypass capacitor close to the V
6. If the distance to the remote sensor is more than
7. For very long distances (up to 100 feet), use
GND
GND
Device Number
D+
D–
Where copper/solder joints are used, ensure they
are in both the D+ and D− paths and at the same
temperature.
Thermocouple effects should not be a major
problem as 1°C corresponds to about 240 mV, and
thermocouple voltages are about 3 mV/°C of
temperature difference. Unless there are two
thermocouples with a big temperature differential
between them, thermocouple voltages should be
much less than 240 mV.
pin, and 2200 pF input filter capacitors across D+,
D− close to the ADM1021A.
eight inches, the use of twisted pair cable is
recommended. This works up to about 6 to 12 feet.
shielded twisted pair, such as Belden #8451
microphone cable. Connect the twisted pair to D+
and D− and the shield to GND close to the
ADM1021A. Leave the remote end of the shield
unconnected to avoid ground loops.
Figure 18. Arrangement of Signal Tracks
Temperature Range
0°C to +100°C
0°C to +100°C
0°C to +100°C
10MIL
10MIL
10MIL
10MIL
10MIL
10MIL
10MIL
10MIL
10MIL
10MIL
10MIL
http://onsemi.com
DD
ADM1021A
16−Lead QSOP
16−Lead QSOP
16−Lead QSOP
Package Type
14
Application Circuits
ADM1021A, using a discrete sensor transistor connected
via a shielded, twisted pair cable. The pullups on SCLK,
SDATA, and ALERT are required only if they are not
already provided elsewhere in the system.
interfaced directly to the SMBus of an I/O chip. Figure 20
shows how the ADM1021A might be integrated into a
system using this type of I/O controller.
CD−ROM
2N3904
* C1 IS OPTIONAL
2 USB PORTS
2 IDE PORTS
DISPLAY
DISPLAY
CACHE
USB
Figure 19 shows a typical application circuit for the
The SCLK and SDATA pins of the ADM1021A can be
Figure 20. Typical System Using ADM1021A
USB
HARD
DISK
SHIELD
Figure 19. Typical Application Circuit
C1*
I/O CONTROLLER
(FIRMWARE HUB)
PROCESSOR
Package Option
D+
D–
ADM1021A
GMCH
HUB
ICH
FWH
GND
RQ−16
RQ−16
RQ−16
SYSTEM BUS
SDATA
ALERT
STBY
SCLK
ADD0
ADD1
V
DD
PCI BUS
PCI SLOTS
MEMORY
SYSTEM
SET TO REQUIRED
ADDRESS
SUPER
0.1µ F
I/O
2500 Tape & Reel
1000 Tape & Reel
ALERT
Shipping
ALL
D–
98 Tube
OUT
ADM1021A
I/O
IN
10k
3.3 V
SDATA
SMBus
TO CONTROL
CHIP
†
SCLK
D+