interface compatible with SMBus 2.0. Using an 8-bit
危鈭?/div>
ADC, the LM96000 measures:
鈥?the temperature of two remote diode connected transis-
tors as well as its own die
鈥?the VCCP, 2.5V, 3.3VSBY, 5.0V, and 12V supplies (in-
ternal scaling resistors).
To set fan speed, the LM96000 has three PWM outputs that
are each controlled by one of three temperature zones. High
and low PWM frequency ranges are supported. The
LM96000 includes a digital filter that can be invoked to
smooth temperature readings for better control of fan speed.
The LM96000 has four tachometer inputs to measure fan
speed. Limit and status registers for all measured values are
included.
n
n
n
n
n
n
n
n
Noise filtering of temperature reading for fan control
1.0藲C digital temperature sensor resolution
3 PWM fan speed control outputs
Provides high and low PWM frequency ranges
4 fan tachometer inputs
Monitors 5 VID control lines
24-pin TSSOP package
XOR-tree test mode
Key Specifications
Voltage Measurement Accuracy
Resolution
Temperature Sensor Accuracy
Temperature Range
鈥?LM96000 Operational
鈥?Remote Temp Accuracy
n
Power Supply Voltage
n
Power Supply Current
n
n
n
n
鹵
2% FS (max)
8-bits, 1藲C
鹵
3藲C (max)
0藲C to +85藲C
0藲C to +125藲C
+3.0V to +3.6V
0.53 mA
Features
n
2-wire, SMBus 2.0 compliant, serial digital interface
n
8-bit
危鈭?/div>
ADC
n
Monitors VCCP, 2.5V, 3.3 VSBY, 5.0V, and 12V
motherboard/processor supplies
n
Monitors 2 remote thermal diodes
n
Programmable autonomous fan control based on
temperature readings
Applications
n
Desktop PC
n
Microprocessor based equipment
(e.g. Base-stations, Routers, ATMs, Point of Sales)
Block Diagram
20084601
漏 2004 National Semiconductor Corporation
DS200846
www.national.com
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