General Description
The MAX1619 is a precise digital thermometer that reports the temperature of both a remote sensor and its own package. The remote sensor is a diode-connected transistor—typically a low-cost, easily mounted 2N3904 NPN type—that replaces conventional thermistors or thermocouples. Remote accuracy is ±3°C for multiple transistor manufacturers, with no calibration needed. The remote channel 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. Measurements can be done automatically and autonomously, with the conversion rate programmed by the user or programmed to operate in a single-shot mode. The adjustable rate allows the user to control the supply-current drain.
The MAX1619 is nearly identical to the popular MAX1617A, with the additional feature of an overtemperature alarm output (OVERT) that responds to the remote temperature; this is optimal for fan control.
Features
♦ Two Channels Measure Both Remote and Local Temperatures
♦ No Calibration Required
♦ SMBus 2-Wire Serial Interface
♦ Programmable Under/Overtemperature Alarms
♦ OVERT Output for Fan Control
♦ Supports SMBus Alert Response
♦ Supports Manufacturer and Device ID Codes
♦ Accuracy ±2°C (+60°C to +100°C, local) ±3°C (-40°C to +125°C, local) ±3°C (+60°C to +100°C, remote)
♦ 3µA (typ) Standby Supply Current
♦ 70µA (max) Supply Current in Auto-Convert Mode
♦ +3V to +5.5V Supply Range
♦ Write-Once Protection
♦ Small 16-Pin QSOP Package
Applications
- Desktop and Notebook
- Central Office
- Computers
- Telecom Equipment
- Smart Battery Packs
- Test and Measurement
- LAN Servers
- Multichip Modules
- Industrial Controls
Feature
- Fast Conversion Time: 20μsec (MAX161)
- No Missing Codes Over Temperature
- On Chip 8x 8 Dual Port RAM
- Interfaces Directly To Z80/8085/6800
- Ratiometric Capability
- Interleaved DMA Operation
Applications
- Automatic Test Equipment
- Data Loggers
- Digital Signal Processing
- Process Control
- Robotics
(Picture: Pinout)
