Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsMAX6695YAUB+

General Description

The MAX6695/MAX6696 are precise, dual-remote, and

local digital temperature sensors. They accurately mea-

sure the temperature of their own die and two remote

diode-connected transistors, and report the tempera-

ture in digital form on a 2-wire serial interface. The

remote diode is typically the emitter-base junction of a

common-collector PNP on a CPU, FPGA, GPU, or ASIC.

The 2-wire serial interface 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 MAX6695/MAX6696 can func-

tion autonomously with a programmable conversion

rate, which allows control of supply current and temper-

ature update rate to match system needs. For conver-

sion rates of 2Hz or less, the temperature is

represented as 10 bits + sign with a resolution of

+0.125°C. When the conversion rate is 4Hz, output data

is 7 bits + sign with a resolution of +1°C. The MAX6695/

MAX6696 also include an SMBus timeout feature to

enhance system reliability.

Remote temperature sensing accuracy is ±1.5°C be-

tween +60°C and +100°C with no calibration needed.

The MAX6695/MAX6696 measure temperatures from

-40°C to +125°C. In addition to the SMBus ALERT out-

put, the MAX6695/MAX6696 feature two overtempera-

ture limit indicators (OT1 and OT2), which are active

only while the temperature is above the corresponding

programmable temperature limits. The OT1 and OT2

outputs are typically used for fan control, clock throt-

tling, or system shutdown.

The MAX6695 has a fixed SMBus address. The

MAX6696 has nine different pin-selectable SMBus

addresses. The MAX6695 is available in a 10-pin

μMAX

and the MAX6696 is available in a 16-pin QSOP

package. Both operate throughout the -40°C to +125°C

temperature range.

Applications

Notebook Computers

Desktop Computers

Servers

Workstations

Test and Measurement Equipment

Features

♦ Measure One Local and Two Remote

Temperatures

♦ 11-Bit, +0.125°C Resolution

♦ High Accuracy ±1.5°C (max) from +60°C to +100°C

(Remote)

♦ ACPI Compliant

♦ Programmable Under/Overtemperature Alarms

♦ Programmable Conversion Rate

♦ Three Alarm Outputs: ALERT, OT1, and OT2

♦ SMBus/I

C-Compatible Interface

♦ Compatible with 65nm Process Technology

(Y Versions)

MAX6695/MAX6696

Dual Remote/Local Temperature Sensors with

SMBus Serial Interface

________________________________________________________________

Maxim Integrated Products

Ordering Information

Typical Operating Circuit

19-3183; Rev 3; 4/11

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

PART TEMP RANGE PIN-PACKAGE

MAX6695AUB+ -40°C to +125°C 10 μMAX

MAX6695YAUB+ -40°C to +125°C 10 μMAX

MAX6696AEE+ -40°C to +125°C 16 QSOP

MAX6696YAEE+ -40°C to +125°C 16 QSOP

Devices are also available in tape-and-reel packages. Specify

tape and reel by adding “T” to the part number when ordering.

Denotes a lead(Pb)-free/RoHS-compliant package.

Pin Configurations appear at end of data sheet.

CLOCK

DATA

TO SYSTEM

SHUTDOWN

GND

OT2

SMBCLK

OT1

SMBDATA

INTERRUPT

TO μP

0.1μF

DXN

DXP1

47Ω

10kΩ

EACH

ALERT

+3.3V

CPU

TO CLOCK

THROTTLING

DXP2

GRAPHICS

PROCESSOR

MAX6695

Typical Operating Circuits continued at end of data sheet.

μMAX is a registered trademark of Maxim Integrated Products, Inc.

Summary of content (19 pages)

PAGE 1
9-3183; Rev 3; 4/11 Dual Remote/Local Temperature Sensors with SMBus Serial Interface The MAX6695/MAX6696 are precise, dual-remote, and local digital temperature sensors. They accurately measure the temperature of their own die and two remote diode-connected transistors, and report the temperature in digital form on a 2-wire serial interface. The remote diode is typically the emitter-base junction of a common-collector PNP on a CPU, FPGA, GPU, or ASIC.
PAGE 2
MAX6695/MAX6696 Dual Remote/Local Temperature Sensors with SMBus Serial Interface ABSOLUTE MAXIMUM RATINGS VCC ...........................................................................-0.3V to +6V DXP1, DXP2................................................-0.3V to (VCC + 0.3V) DXN ......................................................................-0.3V to +0.8V SMBCLK, SMBDATA, ALERT ...................................-0.3V to +6V RESET, STBY, ADD0, ADD1, OT1, OT2 ...................-0.
PAGE 3
Dual Remote/Local Temperature Sensors with SMBus Serial Interface (VCC = +3.0V to +3.6V, TA = 0°C to +125°C, unless otherwise noted. Typical values are at VCC = +3.3V and TA = +25°C) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS ALERT, OT1, OT2 Output Low Sink Current VOL = 0.4V 6 mA Output High Leakage Current VOH = 3.6V 1 μA 0.3 V INPUT PIN, ADD0, ADD1 (MAX6696) Logic Input Low Voltage VIL Logic Input High Voltage VIH 2.
PAGE 4
Typical Operating Characteristics (VCC = 3.3V, TA = +25°C, unless otherwise noted.) AVERAGE OPERATING SUPPLY CURRENT vs. CONVERSION RATE CONTROL REGISTER VALUE 3 2 1 500 4 TEMPERATURE ERROR (°C) 4 5 MAX6695 toc02 5 600 OPERATING SUPPLY CURRENT (μA) MAX6695 toc01 STANDBY SUPPLY CURRENT (μA) 6 TEMPERATURE ERROR vs. REMOTE-DIODE TEMPERATURE 400 300 200 MAX6695 toc03 STANDBY SUPPLY CURRENT vs. SUPPLY VOLTAGE 3 REMOTE CHANNEL1 2 1 0 -1 REMOTE CHANNEL2 -2 100 -3 0 -5 -4 0 3.1 3.2 3.3 3.
PAGE 5
Dual Remote/Local Temperature Sensors with SMBus Serial Interface PIN MAX6695 MAX6696 1 2 NAME FUNCTION VCC Supply Voltage Input, +3V to +3.6V. Bypass to GND with a 0.1μF capacitor. A 47 series resistor is recommended but not required for additional noise filtering. See Typical Operating Circuit. 2 3 DXP1 Combined Remote-Diode Current Source and A/D Positive Input for Remote-Diode Channel 1. DO NOT LEAVE DXP1 UNCONNECTED; connect DXP1 to DXN if no remote diode is used.
PAGE 6
MAX6695/MAX6696 Dual Remote/Local Temperature Sensors with SMBus Serial Interface Detailed Description The MAX6695/MAX6696 are temperature sensors designed to work in conjunction with a microprocessor or other intelligence in temperature monitoring, protection, or control applications. Communication with the MAX6695/MAX6696 occurs through the SMBus serial interface and dedicated alert pins. The overtemperature alarms OT1 and OT2 are asserted if the softwareprogrammed temperature thresholds are exceeded.
PAGE 7
Dual Remote/Local Temperature Sensors with SMBus Serial Interface MAX6695/MAX6696 VCC (RESET) RESET/ UVLO CIRCUITRY 3 DXP1 MUX DXN DXP2 REMOTE1 REMOTE2 CONTROL LOGIC ADC LOCAL DIODE FAULT ALERT (STBY) SMBus S Q 8 READ SMBDATA 8 WRITE SMBCLK R REGISTER BANK 7 COMMAND BYTE REMOTE TEMPERATURES OT1 Q S (ADD0) ADDRESS DECODER (ADD1) LOCAL TEMPERATURES R ALERT THRESHOLD ALERT RESPONSE ADDRESS OT2 OT1 THRESHOLDS Q S R OT2 THRESHOLDS () ARE FOR MAX6696 ONLY. Figure 1.
PAGE 8
MAX6695/MAX6696 Dual Remote/Local Temperature Sensors with SMBus Serial Interface In this example, the effect of the series resistance and the ideality factor partially cancel each other. Discrete Remote Diodes When the remote-sensing diode is a discrete transistor, its collector and base must be connected together. Table 1 lists examples of discrete transistors that are appropriate for use with the MAX6695/MAX6696.
PAGE 9
Dual Remote/Local Temperature Sensors with SMBus Serial Interface MAX6695/MAX6696 Write Byte Format S ADDRESS WR ACK COMMAND 7 bits ACK DATA 8 bits Slave Address: equivalent to chip-select line of a 3-wire interface ACK P 8 bits Command Byte: selects which register you are writing to 1 Data Byte: data goes into the register set by the command byte (to set thresholds, configuration masks, and sampling rate) Read Byte Format ADDRESS WR ACK 7 bits COMMAND ACK RD ACK 7 bits Command Byt
PAGE 10
MAX6695/MAX6696 Dual Remote/Local Temperature Sensors with SMBus Serial Interface extended temperature register (11h) (Table 3), which extends the temperature data to 10 bits + sign and the resolution to +0.125°C per LSB (Table 4). When a conversion is complete, the main register and the extended register are updated almost simultaneously.
PAGE 11
Dual Remote/Local Temperature Sensors with SMBus Serial Interface MAX6695/MAX6696 Table 5.
PAGE 12
MAX6695/MAX6696 Dual Remote/Local Temperature Sensors with SMBus Serial Interface Table 5. Command-Byte Register Bit Assignments (continued) REGISTER ADDRESS POR STATE HYST 21 h 0000 1010 (10°C) RDID FE h 4D h FUNCTION Temperature hysteresis for OT1 and OT2 Read manufacturer ID The POR state of both internal and external ALERT lowtemperature limit registers is 1100 1001 or -55°C. Use bit 3 of the configuration register to select remote 1 or remote 2 when reading or writing remote thresholds.
PAGE 13
Dual Remote/Local Temperature Sensors with SMBus Serial Interface BIT NAME POR STATE 7(MSB) MASK1 0 Mask ALERT interrupts when 1. 6 RUN/STOP 0 Standby mode control bit. If 1, immediately stops converting and enters standby mode. If zero, it converts in either one-shot or timer mode. 5 Fault Queue 0 Fault queue enables when 1. When set to 1, four consecutive faults must occur before OT2 output is asserted. 4 RFU 0 Reserved.
PAGE 14
MAX6695/MAX6696 Dual Remote/Local Temperature Sensors with SMBus Serial Interface Table 7. Status Register 1 Bit Assignments BIT NAME POR FUNCTION 7(MSB) BUSY 1 A/D is busy converting when 1. 6 LHIGH 0 When 1, internal high-temperature ALERT has tripped, cleared by POR or by reading this status register. If the fault condition still exists, this bit is set again after the next conversion.
PAGE 15
Dual Remote/Local Temperature Sensors with SMBus Serial Interface CONVERSION RATE (Hz) REMOTE CHANNEL 1 CONVERSION PERIOD (s) REMOTE CHANNEL 2 AND LOCAL CONVERSION PERIOD (s) REMOTE CHANNEL 1 BIT 3 BIT 1 BIT0 HEX CONVERSION RATE (Hz) REMOTE CHANNEL 2 AND LOCAL 0 0 0 00h 0.0625 0.125 16 8 0 0 1 01h 0.125 0.25 8 4 0 1 0 02h 0.25 0.5 4 2 0 1 1 03h 0.5 1 2 1 1 0 0 04h 1 2 1 0.5 1 0 1 05h 2 4 0.5 0.25 1 1 0 06h 4 8 0.25 0.125 1 1 1 07h 4 8 0.
PAGE 16
MAX6695/MAX6696 Dual Remote/Local Temperature Sensors with SMBus Serial Interface A tLOW B C tHIGH D E F G H I J K L M SMBCLK SMBDATA tHD:STA tSU:STA tSU:DAT A = START CONDITION B = MSB OF ADDRESS CLOCKED INTO SLAVE C = LSB OF ADDRESS CLOCKED INTO SLAVE D = R/W BIT CLOCKED INTO SLAVE E = SLAVE PULLS SMBDATA LINE LOW tHD:DAT tSU:STO tBUF J = ACKNOWLEDGE CLOCKED INTO SLAVE K = ACKNOWLEDGE CLOCK PULSE L = STOP CONDITION M = NEW START CONDITION F = ACKNOWLEDGE BIT CLOCKED INTO MASTER G
PAGE 17
Dual Remote/Local Temperature Sensors with SMBus Serial Interface 10 mils 10 mils DXP 10 mils DXN MINIMUM 10 mils GND Figure 5. Recommended DXP-DXN PC Traces Leakage currents from PC board contamination must be dealt with carefully since a 20MΩ leakage path from DXP to ground causes about +1°C error. If high-voltage traces are unavoidable, connect guard traces to GND on either side of the DXP-DXN traces (Figure 5).
PAGE 18
Dual Remote/Local Temperature Sensors with SMBus Serial Interface MAX6695/MAX6696 Pin Configurations TOP VIEW N.C. 1 16 N.C. VCC 2 15 STBY 14 ADD0 DXP1 3 VCC 1 DXP1 2 DXN 3 DXP2 OT1 10 OT2 DXN 4 MAX6696 13 OT2 9 SMBDATA DXP2 5 12 SMBDATA 8 ALERT ADD1 6 11 ALERT 4 7 SMBCLK RESET 7 10 OT1 5 6 GND MAX6695 μMAX 9 GND 8 SMBCLK QSOP Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages.
PAGE 19
Dual Remote/Local Temperature Sensors with SMBus Serial Interface REVISION NUMBER REVISION DATE 0 2/04 Initial release 1 5/04 Removed future status from MAX6696 in the Ordering Information table; updated the OT1 and OT2 Overtemperature Alarms section 1, 12 2 11/05 Updated the Features section, Ordering Information table, Electrical Characteristics table, and Effect of Ideality Factor section 1, 2, 6 3 4/11 DESCRIPTION PAGES CHANGED — Added lead(Pb)-free and tape-and-reel options to the Orde