General Description
 The MAX6639 monitors its own temperature and one external diode-connected transistor or the temperatures of two external diode-connected transistors, typically available in CPUs, FPGAs, or GPUs.
The 2-wire serial interface accepts standard System Management Bus (SMBusTM) write byte, read byte, send byte, and receive byte commands to read the temperature data and program the alarm thresholds.
Temperature data can be read at any time over the SMBus, and three programmable alarm outputs can be used to generate interrupts, throttle signals, or overtemperature shutdown signals.
The temperature data is also used by the internal dual-PWM fan-speed controller to adjust the speed of up to two cooling fans, thereby minimizing noise when the system is running cool, but providing maximum cooling when power dissipation increases.
Speed control is accomplished by tachometer feedback from the fan, so that the speed of the fan is controlled, not just the PWM duty cycle.
Accuracy of speed measurement is ±4%.
The MAX6639 is available in 16-pin QSOP and 16-pin thin QFN 5mm x 5mm packages.
It operates from 3.0V to 3.6V and consumes just 500μA of supply current.

Features
* Two Thermal-Diode Inputs
* Up to 25kHz PWM Output Frequency
* Three Selectable SMBus Addresses
* Local Temperature Sensor
* 1°C Remote Temperature Accuracy
* Two PWM Outputs for Fan Drive (Open Drain; Can be Pulled Up to +13.5V)
* Programmable Fan-Control Characteristics
* Automatic Fan Spin-Up Ensures Fan Start
* Controlled Rate-of-Change Ensures Unobtrusive Fan-Speed Adjustments
* ±3% Fan-Speed Measurement Accuracy
* Temperature Monitoring Begins at POR for Fail- Safe System Protection
* OT and THERM Outputs for Throttling or Shutdown
* Measures Temperatures Up to +150°C
* MAX6639F is Optimized for n = 1.021 for Penryn Compatability

Applications
* Desktop Computers
* Notebook Computers
* Projectors
* Servers
* Networking Equipment

MAX6639AEE
MAX6639ATE
MAX6639FAEE
MAX6639F

Trackback :: http://datasheetblog.com/trackback/1626

댓글을 달아 주세요 Comment

The ISL6256, ISL6256A is a highly integrated battery charger controller for Li-Ion/Li-Ion polymer batteries. High Efficiency is achieved by a synchronous buck topology and the use of a MOSFET, instead of a diode, for selecting power from the adapter or battery. The low side MOSFET emulates a diode at light loads to improve the light load efficiency and prevent
system bus boosting.
The constant output voltage can be selected for 2, 3 and 4 series Li-Ion cells with 0.5% accuracy over-temperature. It can also be programmed between 4.2V+5%/cell and 4.2V- 5%/cell to optimize battery capacity. When supplying the load and battery charger simultaneously, the input current limit for the AC adapter is programmable to within 3% accuracy to avoid overloading the AC adapter, and to allow the system to make efficient use of available adapter power for charging. It also has a wide range of programmable charging current. The
ISL6256, ISL6256A provides outputs that are used to monitor the current drawn from the AC adapter, and monitor for the presence of an AC adapter. The ISL6256, ISL6256A automatically transitions from regulating current mode to regulating voltage mode.
ISL6256, ISL6256A has a feature for automatic power source selection by switching to the battery when the AC adapter is removed or switching to the AC adapter when the AC adapter
is available. It also provides a DC adapter monitor to support aircraft power applications with the option of no battery charging.

Features
• ±0.5% Charge Voltage Accuracy (-10°C to +100°C)
• ±3% Accurate Input Current Limit
• ±3% Accurate Battery Charge Current Limit
• ±25% Accurate Battery Trickle Charge Current Limit
• Programmable Charge Current Limit, Adapter Current Limit and Charge Voltage
• Fixed 300kHz PWM Synchronous Buck Controller with Diode Emulation at Light Load
• Overvoltage Protection
• Output for Current Drawn from AC Adapter
• AC Adapter Present Indicator
• Fast Input Current Limit Response
• Input Voltage Range 7V to 25V
• Support 2-, 3- and 4-Cells Battery Pack
• Up to 17.64V Battery-Voltage Set Point
• Control Adapter Power Source Select MOSFET
• Thermal Shutdown
• Aircraft Power Capable
• DC Adapter Present Indicator
• Battery Discharge MOSFET Control
• Less than 10μA Battery Leakage Current
• Supports Pulse Charging
• Pb-Free Plus Anneal Available (RoHS Compliant)

Applications
• Notebook, Desknote and Sub-notebook Computers
• Personal Digital Assistant

ISL6256HRZ
ISL6256HAZ
ISL6256AHRZ
ISL6256AHAZ

Trackback :: http://datasheetblog.com/trackback/1300

댓글을 달아 주세요 Comment