MAX1617AMEE Integrated Circuit Chip Remote/Local Temperature Sensor with SMBus Serial Interface

Remote/Local Temperature Sensor with SMBus Serial Interface

General Description

The MAX1617A (patents pending) 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 MAX1617A is nearly identical to the popular MAX1617, but has improved SMBus timing specifications, improved bus collision immunity, software manufacturer and device identification available via the serial interface, and a poweron reset function that can force a reset of the slave address via the serial interface.

Applications

Desktop and Notebook     Central Office

Computers                        Telecom Equipment

Smart Battery Packs         Test and Measurement

LAN Servers                      Multichip Modules

Industrial Controls

Features

♦ Two Channels: Measures Both Remote and Local Temperatures

♦ No Calibration Required

♦ SMBus 2-Wire Serial Interface

♦ Programmable Under/Overtemperature Alarms

♦ 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

♦ Small 16-Pin QSOP Package

ABSOLUTE MAXIMUM RATINGS

V_CC to GND..............................................................-0.3V to +6V

DXP, ADD_ to GND ....................................-0.3V to (V_CC + 0.3V)

DXN to GND ..........................................................-0.3V to +0.8V

SMBCLK, SMBDATA, ALERT, STBY to GND ...........-0.3V to +6V

SMBDATA, ALERT Current .................................-1mA to +50mA

DXN Current .......................................................................±1mA

ESD Protection (SMBCLK, SMBDATA,

    ALERT, Human Body Model) ......................................... 4000V

ESD Protection (other pins, Human Body Model)..............2000V

Continuous Power Dissipation (TA = +70°C)

    QSOP (derate 8.30mW/°C above +70°C).....................667mW

Operating Temperature Range .........................-55°C to +125°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +165°C

Lead Temperature (soldering, 10sec) .............................+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.

Pin Configuration

Typical Operating Circuit