MAX6648/MAX6692 19-2545 Rev 4 6/08 Precision SMBus-Compatible Remote/Local Temperature Sensors with Overtemperature Alarms General Description Features Dual Channel Measures Remote and Local The MAX6648/MAX6692 are precise, two-channel digi- Temperature tal temperature sensors. They accurately measure the temperature of their own die and a remote PN junction, +0.125C Resolution and report the temperature in digital form using a 2-wire High Accuracy 0.8C (max) from +25C to +125C serial interface. The remote PN junction is typically the (Remote), and 2C (max) from +60C to +100C emitter-base junction of a common-collector PNP on a (Local) CPU, FPGA, or ASIC. Two Alarm Outputs: ALERT and OVERT The 2-wire serial interface accepts standard System Two Default OVERT Thresholds Available Management Bus (SMBus) write byte, read byte, MAX6648: +110C send byte, and receive byte commands to read the MAX6692: +85C temperature data and to program the alarm thresholds. Programmable Conversion Rate To enhance system reliability, the MAX6648/MAX6692 include an SMBus timeout. A fault queue prevents the SMBus-Compatible Interface ALERT and OVERT outputs from setting until a fault has SMBus Timeout been detected one, two, or three consecutive times Programmable Under/Overtemperature Alarm (programmable). Thresholds The MAX6648/MAX6692 provide two system alarms: Compatible with 90nm, 65nm, and 45nm Process ALERT and OVERT. ALERT asserts when any of four tem- Technology perature conditions are violated: local overtemperature, remote overtemperature, local undertemperature, or Ordering Information remote undertemperature. OVERT asserts when the tem- perature rises above the value in either of the two OVERT PIN- MEASURED limit registers. The OVERT output can be used to activate PART PACKAGE TEMP RANGE a cooling fan, or to trigger a system shutdown. MAX6648MUA 8 MAX 0C to +125C Measurements can be done autonomously, with the MAX6648YMUA 8 MAX 0C to +125C conversion rate programmed by the user, or in a single- shot mode. The adjustable conversion rate allows the MAX6692MUA 8 MAX 0C to +125C user to optimize supply current and temperature MAX6692MSA 8 SO 0C to +125C update rate to match system needs. MAX6692YMUA 8 MAX 0C to +125C Remote accuracy is 0.8C maximum error between MAX6692YMSA 8 SO 0C to +125C +25C and +125C with no calibration needed. The MAX6648/MAX6692 operate from -55C to +125C, and Note: All devices operate over the -55C to +125C temperature range. measure temperatures between 0C and +125C. The MAX6648 is available in an 8-pin MAX package, and the Typical Operating Circuit MAX6692 is available in 8-pin MAX and SO packages. Applications 3.3V 0.1F 200 Desktop Computers Notebook Computers V CC 10k EACH Servers DXP DATA SDA Thin Clients MAX6648 CLOCK SCLK Workstations MAX6692 ALERT INTERRUPTED TO P DXN Test and Measurement 2200pF OVERT TO FAN DRIVER OR Multichip Modules GND SYSTEM SHUTDOWN P SMBus is a trademark of Intel Corp. Pin Configuration and Functional Diagram appear at end of MAX is a registered trademark of Maxim Integrated Products, Inc. data sheet. Maxim Integrated Products 1 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.Precision SMBus-Compatible Remote/Local Temperature Sensors with Overtemperature Alarms ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) ESD Protection (all pins, Human Body Model)................2000V V ...........................................................................-0.3V to +6V Junction Temperature......................................................+150C CC DXP.............................................................-0.3V to (V + 0.3V) Operating Temperature Range .........................-55C to +125C CC DXN .......................................................................-0.3V to +0.8V Storage Temperature Range .............................-65C to +150C SCLK, SDA, ALERT, OVERT.....................................-0.3V to +6V Lead Temperature (soldering, 10s) .................................+300C SDA, ALERT, OVERT Current .............................-1mA to +50mA DXN Current .......................................................................1mA Continuous Power Dissipation (T = +70C) A 8-Pin MAX (derate 5.9mW/C above +70C) .............471mW 8-Pin SO (derate 5.9mW/C above +70C)..................471mW 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. ELECTRICAL CHARACTERISTICS (V = 3.0V to 5.5V, T = -55C to +125C, unless otherwise specified. Typical values are at V = 3.3V and T = +85C.) (Note 1) CC A CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V 3.0 5.5 V CC 0.125 C Temperature Resolution 10 Bits V = 3.3V, CC T = +25C to +125C -0.8 +0.8 RJ T = +85C A V = 3.3V, CC T = +60C to +100C -1.0 +1.0 RJ Remote Temperature Error +60C T C A n = 1.008 T = 0C to +125C -1.6 +1.6 RJ +100C V = 3.3V, +0C CC T = 0C to +125C -3.0 +3.0 RJ T +100C A T = +60C to +100C -2.0 +2.0 A Local Temperature Error V = 3.3V C CC T = 0C to +125C -3.0 +3.0 A T = + 60C to +10 0C -4. 0 Local Temperature Error A V = 3.3V C C C (MAX6648Y/MAX6692Y) T = 0C to +125C -4.4 A Supply Sensitivity of Temperature 0.2 C/V Error Undervoltage Lockout (UVLO) UVLO Falling edge of V disables ADC 2.4 2.7 2.95 V CC Threshold UVLO Hysteresis 90 mV Power-On-Reset (POR) Threshold V falling edge 2.0 V CC POR Threshold Hysteresis 90 mV Standby Supply Current SMBus static 3.5 12 A Operating Current During conversion 0.45 0.8 mA 0.25 conversions per second 40 80 Average Operating Current A 2 conversions per second 250 400 Conversion Time t From stop bit to conversion completion 95 125 156 ms CONV Conversion Time Error -25 +25 % DXP and DXN Leakage Current Standby mode 100 nA 2 MAX6648/MAX6692