Complete Thermal System
Management Controller

ADM1026


Rev. A
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However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
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Tel: 781.329.4700 www.analog.com
Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved.
FEATURES
Up to 19 analog measurement channels (including internal
measurements)
Up to 8 fan speed measurement channels
Up to 17 general-purpose logic I/O pins
Remote temperature measurement with remote diode (two
channels)
On-chip temperature sensor
Analog and PWM fan speed control outputs
2-wire serial system management bus (SMBus)
8 kB on-chip EEPROM
Full SMBus 1.1 support includes packet error checking (PEC)
Chassis intrusion detection
Interrupt output (SMBAlert)
Reset input, reset outputs
Thermal interrupt (THERM) output
Limit comparison of all monitored values
APPLICATIONS
Network servers and personal computers
Telecommunications equipment
Test equipment and measuring instruments

D2–/A
IN9
(0V – +2.5V)
D2+/A
IN8
(0V – +2.5V)
A
IN7
(0V – +2.5V)
A
IN6
(0V – +2.5V)
TO GPIO
REGISTERS
100kΩ
100kΩ
V
CC
V
CC
V
CC
FAN
SPEED
COUNTER
INPUT
ATTENUATORS
AND
ANALOG
MULTIPLEXER
GPIO
REGISTERS
SERIAL BUS
INTERFACE
ADDRESS
POINTER
REGISTER
BAND GAP
TEMPERATURE
SENSOR
AUTOMATIC
FAN SPEED
CONTROL
8k BYTES
EEPROM
8-BIT
ADC
BAND GAP
REFERENCE
V
BAT
+5 V
IN
–12 V
IN
+12 V
IN
+V
CCP
A
IN0
(0V – +3V)
A
IN1
(0V – +3V)
A
IN2
(0V – +3V)
A
IN3
(0V – +3V)
A
IN4
(0V – +3V)
A
IN5
(0V – +3V)
D1+
D1–/NTESTIN
DGND
DAC
AGND V
REF
(1.82V OR 2.5V)
SCLSDA 3.3V MAIN
ADD/
NTESTOUT
FAN7/GPIO7
FAN6/GPIO6
FAN5/GPIO5
FAN4/GPIO4
FAN3/GPIO3
FAN2/GPIO2
FAN1/GPIO1
FAN0/GPIO0
GPIO15
GPIO14
GPIO13
GPIO12
GPIO11
GPIO10
GPIO9
GPIO8
PWM
3.3V STBY
GPIO16/THERM
CI
ADM1026
INT
RESET IN
V
CC
V
CC
100kΩ
RESETMAIN
RESETSTBY
PWM REGISTER
AND CONTROLLER
LIMIT
COMPARATORS
INT MASK
REGISTERS
INTERRUPT
MASKING
CONFIGURATION
REGISTERS
VALUE AND
LIMIT
REGISTERS
3.3V MAIN
RESET
GENERATOR
3.3V STBY
RESET
GENERATOR
INTERRUPT
STATUS
REGISTERS
ANALOG
OUTPUT REGISTER
AND 8-BIT DAC
02657-A
-
001

Figure 1. Functional Block Diagram