MAX1805

MAX1668/MAX1805† 19-1766; Rev 0; 8/00 Multichannel Remote/Local Temperature Sensor ________________General Description The MAX1668/MAX1805 are precise multichannel digital thermometers that report the temperature of all remote sensors and their own packages. The remote sensors are diode-connected transistors—typically lowcost, easily mounted 2N3904 NPN types—that replace conventional thermistors or thermocouples. Remote accuracy is ±3°C for multiple transistor manufacturers, with no calibration needed. The remote channels can also measure the die temperature of other ICs, such as microprocessors, that contain an on-chip, diode-connected transistor. The 2-wire serial interface accepts standard System Management Bus (SMBus™) Write Byte, Read Byte, Send Byte, and Receive Byte commands to program the alarm thresholds and to read temperature data. The data format is 7 bits plus sign, with each bit corresponding to 1°C, in two’s-complement format. The MAX1668/MAX1805 are available in small, 16-pin QSOP surface-mount packages. ________________________Applications Desktop and Notebook Computers Central Office Telecom Equipment LAN Servers Test and Measurement Industrial Controls Multichip Modules ____________________________Features o Multichannel 4 Remote, 1 Local (MAX1668) 2 Remote, 1 Local (MAX1805) o No Calibration Required o SMBus 2-Wire Serial Interface o Programmable Under/Overtemperature Alarms o Supports SMBus Alert Response o Accuracy ±2°C (+60°C to +100°C, local...