Product category: Analogue and Mixed Signal ICs
News Release from: National Semiconductor | Subject: LM63
Edited by the Electronicstalk Editorial Team on 17 September 2002
Sensor provides a degree of control over
fans
The LM63 is a +/-1C accuracy remote diode temperature sensor with integrated fan control.
The LM63 is a +/-1C accuracy remote diode temperature sensor with integrated fan control The pulsewidth modulated (PWM) signal output of National's LM63 controls the fan speed based on the temperature of the remote diode sensor
This article was originally published on Electronicstalk on 5 Jan 2001 at 8.00am (UK)
Related stories
Dual-port Gigabit Ethernet transceiver
National Semiconductor has announced the DP83862, a low-cost, highly integrated dual-port 10/100/1000 physical layer transceiver.
World's smallest multifunction supervisory ICs
National Semiconductor has announced a family of supervisory ICs with a variety of factory-programmable features that can be configured in hundreds of possible combinations.
The flexibility in fan control programming in this device enables the same design to be used with different fans, processors or remote diodes, which will reduce design cost for systems providers.
"National Semiconductor has one of the industry's broadest portfolios of thermal management products, and to continue this trend, we are adding products with integrated fan control, like the LM63, to our portfolio", said Uwe Kopp, marketing manager for National's data conversion systems product group in Europe.
"As a leader in temperature sensor innovation, National continues to drive the market by developing products with the highest accuracy, lowest power and smallest packaging in the industry".
Further reading
Leadless leadframe package shrinks LDO
National Semiconductor has introduced a full-featured 500mA LDO regulator for medium-current applications in computing devices and portable products.
Boomer shrinks stereo headphone amplification
New from National Semiconductor, the LM4811 Boomer audio amplifier is a 105mW stereo headphone amplifier for use in 3 and 5V systems requiring a headphone output and volume control.
National's LM63 is targeted for applications in PC notebooks, desktops, workstations, servers, and other CPU-based systems such as thin clients.
It can also be used in basestations, routers, fan modules, or any system that requires fan control based on temperature.
The LM63 has a local and remote diode temperature sensor, which senses the temperature of an integrated diode in a target IC, such as a Pentium III or IV processor, or a discrete transistor, such as 2N3904, and its own location.
It has +/-1C accuracy including the quantisation error and features a programmable PWM output, which controls the fan speed based on the remote diode temperature.
This device also has an eight-step look-up table, which can be programmed to create a non-linear transfer function fan control based on the temperature.
This allows designers to avoid the resonant frequency of the fan or housing cabinet and achieve better acoustic performance in their systems.
This product contains a fan tachometer-monitoring system that monitors the fan tachometer correctly when the fan voltage is modulated by either a low- or high-frequency PWM output.
The LM63 also has an offset register, which helps designers maintain accuracy while using CPUs with different nonideality factors or different trace lengths (parasitic resistance) by simply adjusting the register.
The LM63 also incorporates a programmable digital filter to reduce the noise in thermal measurement of integrated diodes.
The LM63 is sampling now in SO-8 packaging and is priced at $2.10 in 1000-unit quantities.
• National Semiconductor: contact details and other news
• Email this article to a colleague
• Register for the free Electronicstalk email newsletter
• Electronicstalk Home Page
