Features: Two Alarm Outputs: ALERT and OVERT
Pin-Programmable Threshold for OVERT Limit
Programmable Under/Overtemperature ALERT Limit
Dual Channel: Measures Remote and Local Temperature
11-Bit, 0.125°C Resolution for Remote Temperature Measurements
High Accuracy ±1°C (max) from +60°C to +100°C (Remote)
No Calibration Required
SMBus/I2C™-Compatible Interface
SMBus Timeout Prevents SMBus LockupApplicationDesktop Computers
Notebook
Computers
Servers
Thin Clients
Workstations
Pin Configurations appear at end of data sheet.
SMBus is a trademark of Intel Corp.
I2C is a trademark of Philips Corp.Pinout
SpecificationsVcc...........................................................................-0.3V to +6V
DXP.............................................................-0.3V to (VCC + 0.3V)
DXN ......................................................................-0.3V to +0.8V
SMBCLK, SMBDATA, ALERT, OVERT ...........................-0.3V to +6V
RESET, INT_SEL, STBY, ADD0, ADD1........................-0.3V to +6V
CRIT1, CRIT0, SENS_SEL ........................................-0.3V to +6V
SMBDATA,ALERT, OVERT, Current .......................-1mA to +50mA
DXN Current .....................................................................±1mA
Continuous Power Dissipation (TA = +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C) ..........664mW
Junction Temperature ..................................................+150°C
Storage Temperature Range .......................-65°C to +150°C
Lead Temperature (soldering, 10s) .............................+300°C
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
DescriptionThe MAX6680/MAX6681 are precise, two-channel digital thermometers. Each accurately measures the temperature of its own die and one remote PN junction and reports the temperature on a 2-wire serial interface. The remote junction can be a diode-connected transistor like the low-cost NPN type 2N3904 or PNP type 2N3906. The remote junction of MAX6681 can also be a commoncollector PNP, such as a substrate PNP of a microprocessor.
The MAX6680/MAX6681 include pin-programmable default temperature thresholds for theOVERT output, which provides fail-safe clock throttling or system shutdown. In addition, the devices are pin programmable to select whether the OVERT output responds to either the local, remote, or both temperatures.
The 2-wire serial interface of MAX6681 accepts standard System Management Bus (SMBus)™ commands such as Write Byte, Read Byte, Send Byte, and Receive Byte to read the temperature data and program the alarm thresholds and conversion rate. The MAX6680/MAX6681 can function autonomously with a programmable conversion rate, which allows the control of supply current and temperature update rate to match system needs. For conversion rates of 4Hz or less, the remote sensor temperature can be represented in extended mode as 10 bits + sign with a esolution of 0.125°C. When the conversion rate is 8Hz, output data is 7 bits + sign with a resolution of 1°C. The MAX6680/MAX6681 also include an SMBus timeout feature to enhance system reliability.
The MAX6681 is an upgrade to the MAX6654. The MAX6680/MAX6681 remote accuracy is ±1°C with no calibration needed. They are available in a 16-pin QSOP package and operate throughout the -55°C to +125°C temperature range.
MAX6681 Data Sheet
